Fix afs_apply_status() to mask off the irrelevant bits from status->mode
when OR'ing them into i_mode. This can happen when a 3rd party chmod
occurs.
Also fix afs_inode_init_from_status() to mask off the mode bits when
initialising i_mode.
Fixes: 260a980317 ("[AFS]: Add "directory write" support.")
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Merge tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull idmapped mounts from Christian Brauner:
"This introduces idmapped mounts which has been in the making for some
time. Simply put, different mounts can expose the same file or
directory with different ownership. This initial implementation comes
with ports for fat, ext4 and with Christoph's port for xfs with more
filesystems being actively worked on by independent people and
maintainers.
Idmapping mounts handle a wide range of long standing use-cases. Here
are just a few:
- Idmapped mounts make it possible to easily share files between
multiple users or multiple machines especially in complex
scenarios. For example, idmapped mounts will be used in the
implementation of portable home directories in
systemd-homed.service(8) where they allow users to move their home
directory to an external storage device and use it on multiple
computers where they are assigned different uids and gids. This
effectively makes it possible to assign random uids and gids at
login time.
- It is possible to share files from the host with unprivileged
containers without having to change ownership permanently through
chown(2).
- It is possible to idmap a container's rootfs and without having to
mangle every file. For example, Chromebooks use it to share the
user's Download folder with their unprivileged containers in their
Linux subsystem.
- It is possible to share files between containers with
non-overlapping idmappings.
- Filesystem that lack a proper concept of ownership such as fat can
use idmapped mounts to implement discretionary access (DAC)
permission checking.
- They allow users to efficiently changing ownership on a per-mount
basis without having to (recursively) chown(2) all files. In
contrast to chown (2) changing ownership of large sets of files is
instantenous with idmapped mounts. This is especially useful when
ownership of a whole root filesystem of a virtual machine or
container is changed. With idmapped mounts a single syscall
mount_setattr syscall will be sufficient to change the ownership of
all files.
- Idmapped mounts always take the current ownership into account as
idmappings specify what a given uid or gid is supposed to be mapped
to. This contrasts with the chown(2) syscall which cannot by itself
take the current ownership of the files it changes into account. It
simply changes the ownership to the specified uid and gid. This is
especially problematic when recursively chown(2)ing a large set of
files which is commong with the aforementioned portable home
directory and container and vm scenario.
- Idmapped mounts allow to change ownership locally, restricting it
to specific mounts, and temporarily as the ownership changes only
apply as long as the mount exists.
Several userspace projects have either already put up patches and
pull-requests for this feature or will do so should you decide to pull
this:
- systemd: In a wide variety of scenarios but especially right away
in their implementation of portable home directories.
https://systemd.io/HOME_DIRECTORY/
- container runtimes: containerd, runC, LXD:To share data between
host and unprivileged containers, unprivileged and privileged
containers, etc. The pull request for idmapped mounts support in
containerd, the default Kubernetes runtime is already up for quite
a while now: https://github.com/containerd/containerd/pull/4734
- The virtio-fs developers and several users have expressed interest
in using this feature with virtual machines once virtio-fs is
ported.
- ChromeOS: Sharing host-directories with unprivileged containers.
I've tightly synced with all those projects and all of those listed
here have also expressed their need/desire for this feature on the
mailing list. For more info on how people use this there's a bunch of
talks about this too. Here's just two recent ones:
https://www.cncf.io/wp-content/uploads/2020/12/Rootless-Containers-in-Gitpod.pdfhttps://fosdem.org/2021/schedule/event/containers_idmap/
This comes with an extensive xfstests suite covering both ext4 and
xfs:
https://git.kernel.org/brauner/xfstests-dev/h/idmapped_mounts
It covers truncation, creation, opening, xattrs, vfscaps, setid
execution, setgid inheritance and more both with idmapped and
non-idmapped mounts. It already helped to discover an unrelated xfs
setgid inheritance bug which has since been fixed in mainline. It will
be sent for inclusion with the xfstests project should you decide to
merge this.
In order to support per-mount idmappings vfsmounts are marked with
user namespaces. The idmapping of the user namespace will be used to
map the ids of vfs objects when they are accessed through that mount.
By default all vfsmounts are marked with the initial user namespace.
The initial user namespace is used to indicate that a mount is not
idmapped. All operations behave as before and this is verified in the
testsuite.
Based on prior discussions we want to attach the whole user namespace
and not just a dedicated idmapping struct. This allows us to reuse all
the helpers that already exist for dealing with idmappings instead of
introducing a whole new range of helpers. In addition, if we decide in
the future that we are confident enough to enable unprivileged users
to setup idmapped mounts the permission checking can take into account
whether the caller is privileged in the user namespace the mount is
currently marked with.
The user namespace the mount will be marked with can be specified by
passing a file descriptor refering to the user namespace as an
argument to the new mount_setattr() syscall together with the new
MOUNT_ATTR_IDMAP flag. The system call follows the openat2() pattern
of extensibility.
The following conditions must be met in order to create an idmapped
mount:
- The caller must currently have the CAP_SYS_ADMIN capability in the
user namespace the underlying filesystem has been mounted in.
- The underlying filesystem must support idmapped mounts.
- The mount must not already be idmapped. This also implies that the
idmapping of a mount cannot be altered once it has been idmapped.
- The mount must be a detached/anonymous mount, i.e. it must have
been created by calling open_tree() with the OPEN_TREE_CLONE flag
and it must not already have been visible in the filesystem.
The last two points guarantee easier semantics for userspace and the
kernel and make the implementation significantly simpler.
By default vfsmounts are marked with the initial user namespace and no
behavioral or performance changes are observed.
The manpage with a detailed description can be found here:
1d7b902e28
In order to support idmapped mounts, filesystems need to be changed
and mark themselves with the FS_ALLOW_IDMAP flag in fs_flags. The
patches to convert individual filesystem are not very large or
complicated overall as can be seen from the included fat, ext4, and
xfs ports. Patches for other filesystems are actively worked on and
will be sent out separately. The xfstestsuite can be used to verify
that port has been done correctly.
The mount_setattr() syscall is motivated independent of the idmapped
mounts patches and it's been around since July 2019. One of the most
valuable features of the new mount api is the ability to perform
mounts based on file descriptors only.
Together with the lookup restrictions available in the openat2()
RESOLVE_* flag namespace which we added in v5.6 this is the first time
we are close to hardened and race-free (e.g. symlinks) mounting and
path resolution.
While userspace has started porting to the new mount api to mount
proper filesystems and create new bind-mounts it is currently not
possible to change mount options of an already existing bind mount in
the new mount api since the mount_setattr() syscall is missing.
With the addition of the mount_setattr() syscall we remove this last
restriction and userspace can now fully port to the new mount api,
covering every use-case the old mount api could. We also add the
crucial ability to recursively change mount options for a whole mount
tree, both removing and adding mount options at the same time. This
syscall has been requested multiple times by various people and
projects.
There is a simple tool available at
https://github.com/brauner/mount-idmapped
that allows to create idmapped mounts so people can play with this
patch series. I'll add support for the regular mount binary should you
decide to pull this in the following weeks:
Here's an example to a simple idmapped mount of another user's home
directory:
u1001@f2-vm:/$ sudo ./mount --idmap both:1000:1001:1 /home/ubuntu/ /mnt
u1001@f2-vm:/$ ls -al /home/ubuntu/
total 28
drwxr-xr-x 2 ubuntu ubuntu 4096 Oct 28 22:07 .
drwxr-xr-x 4 root root 4096 Oct 28 04:00 ..
-rw------- 1 ubuntu ubuntu 3154 Oct 28 22:12 .bash_history
-rw-r--r-- 1 ubuntu ubuntu 220 Feb 25 2020 .bash_logout
-rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25 2020 .bashrc
-rw-r--r-- 1 ubuntu ubuntu 807 Feb 25 2020 .profile
-rw-r--r-- 1 ubuntu ubuntu 0 Oct 16 16:11 .sudo_as_admin_successful
-rw------- 1 ubuntu ubuntu 1144 Oct 28 00:43 .viminfo
u1001@f2-vm:/$ ls -al /mnt/
total 28
drwxr-xr-x 2 u1001 u1001 4096 Oct 28 22:07 .
drwxr-xr-x 29 root root 4096 Oct 28 22:01 ..
-rw------- 1 u1001 u1001 3154 Oct 28 22:12 .bash_history
-rw-r--r-- 1 u1001 u1001 220 Feb 25 2020 .bash_logout
-rw-r--r-- 1 u1001 u1001 3771 Feb 25 2020 .bashrc
-rw-r--r-- 1 u1001 u1001 807 Feb 25 2020 .profile
-rw-r--r-- 1 u1001 u1001 0 Oct 16 16:11 .sudo_as_admin_successful
-rw------- 1 u1001 u1001 1144 Oct 28 00:43 .viminfo
u1001@f2-vm:/$ touch /mnt/my-file
u1001@f2-vm:/$ setfacl -m u:1001:rwx /mnt/my-file
u1001@f2-vm:/$ sudo setcap -n 1001 cap_net_raw+ep /mnt/my-file
u1001@f2-vm:/$ ls -al /mnt/my-file
-rw-rwxr--+ 1 u1001 u1001 0 Oct 28 22:14 /mnt/my-file
u1001@f2-vm:/$ ls -al /home/ubuntu/my-file
-rw-rwxr--+ 1 ubuntu ubuntu 0 Oct 28 22:14 /home/ubuntu/my-file
u1001@f2-vm:/$ getfacl /mnt/my-file
getfacl: Removing leading '/' from absolute path names
# file: mnt/my-file
# owner: u1001
# group: u1001
user::rw-
user:u1001:rwx
group::rw-
mask::rwx
other::r--
u1001@f2-vm:/$ getfacl /home/ubuntu/my-file
getfacl: Removing leading '/' from absolute path names
# file: home/ubuntu/my-file
# owner: ubuntu
# group: ubuntu
user::rw-
user:ubuntu:rwx
group::rw-
mask::rwx
other::r--"
* tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: (41 commits)
xfs: remove the possibly unused mp variable in xfs_file_compat_ioctl
xfs: support idmapped mounts
ext4: support idmapped mounts
fat: handle idmapped mounts
tests: add mount_setattr() selftests
fs: introduce MOUNT_ATTR_IDMAP
fs: add mount_setattr()
fs: add attr_flags_to_mnt_flags helper
fs: split out functions to hold writers
namespace: only take read lock in do_reconfigure_mnt()
mount: make {lock,unlock}_mount_hash() static
namespace: take lock_mount_hash() directly when changing flags
nfs: do not export idmapped mounts
overlayfs: do not mount on top of idmapped mounts
ecryptfs: do not mount on top of idmapped mounts
ima: handle idmapped mounts
apparmor: handle idmapped mounts
fs: make helpers idmap mount aware
exec: handle idmapped mounts
would_dump: handle idmapped mounts
...
AF_RXRPC sockets use UDP ports in encap mode. This causes socket and dst
from an incoming packet to get stolen and attached to the UDP socket from
whence it is leaked when that socket is closed.
When a network namespace is removed, the wait for dst records to be cleaned
up happens before the cleanup of the rxrpc and UDP socket, meaning that the
wait never finishes.
Fix this by moving the rxrpc (and, by dependence, the afs) private
per-network namespace registrations to the device group rather than subsys
group. This allows cached rxrpc local endpoints to be cleared and their
UDP sockets closed before we try waiting for the dst records.
The symptom is that lines looking like the following:
unregister_netdevice: waiting for lo to become free
get emitted at regular intervals after running something like the
referenced syzbot test.
Thanks to Vadim for tracking this down and work out the fix.
Reported-by: syzbot+df400f2f24a1677cd7e0@syzkaller.appspotmail.com
Reported-by: Vadim Fedorenko <vfedorenko@novek.ru>
Fixes: 5271953cad ("rxrpc: Use the UDP encap_rcv hook")
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vadim Fedorenko <vfedorenko@novek.ru>
Link: https://lore.kernel.org/r/161196443016.3868642.5577440140646403533.stgit@warthog.procyon.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Extend some inode methods with an additional user namespace argument. A
filesystem that is aware of idmapped mounts will receive the user
namespace the mount has been marked with. This can be used for
additional permission checking and also to enable filesystems to
translate between uids and gids if they need to. We have implemented all
relevant helpers in earlier patches.
As requested we simply extend the exisiting inode method instead of
introducing new ones. This is a little more code churn but it's mostly
mechanical and doesnt't leave us with additional inode methods.
Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
The generic_fillattr() helper fills in the basic attributes associated
with an inode. Enable it to handle idmapped mounts. If the inode is
accessed through an idmapped mount map it into the mount's user
namespace before we store the uid and gid. If the initial user namespace
is passed nothing changes so non-idmapped mounts will see identical
behavior as before.
Link: https://lore.kernel.org/r/20210121131959.646623-12-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
The posix acl permission checking helpers determine whether a caller is
privileged over an inode according to the acls associated with the
inode. Add helpers that make it possible to handle acls on idmapped
mounts.
The vfs and the filesystems targeted by this first iteration make use of
posix_acl_fix_xattr_from_user() and posix_acl_fix_xattr_to_user() to
translate basic posix access and default permissions such as the
ACL_USER and ACL_GROUP type according to the initial user namespace (or
the superblock's user namespace) to and from the caller's current user
namespace. Adapt these two helpers to handle idmapped mounts whereby we
either map from or into the mount's user namespace depending on in which
direction we're translating.
Similarly, cap_convert_nscap() is used by the vfs to translate user
namespace and non-user namespace aware filesystem capabilities from the
superblock's user namespace to the caller's user namespace. Enable it to
handle idmapped mounts by accounting for the mount's user namespace.
In addition the fileystems targeted in the first iteration of this patch
series make use of the posix_acl_chmod() and, posix_acl_update_mode()
helpers. Both helpers perform permission checks on the target inode. Let
them handle idmapped mounts. These two helpers are called when posix
acls are set by the respective filesystems to handle this case we extend
the ->set() method to take an additional user namespace argument to pass
the mount's user namespace down.
Link: https://lore.kernel.org/r/20210121131959.646623-9-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
The number of dirent records used by an AFS directory entry should be
calculated using the assumption that there is a 16-byte name field in the
first block, rather than a 20-byte name field (which is actually the case).
This miscalculation is historic and effectively standard, so we have to use
it.
The calculation we need to use is:
1 + (((strlen(name) + 1) + 15) >> 5)
where we are adding one to the strlen() result to account for the NUL
termination.
Fix this by the following means:
(1) Create an inline function to do the calculation for a given name
length.
(2) Use the function to calculate the number of records used for a dirent
in afs_dir_iterate_block().
Use this to move the over-end check out of the loop since it only
needs to be done once.
Further use this to only go through the loop for the 2nd+ records
composing an entry. The only test there now is for if the record is
allocated - and we already checked the first block at the top of the
outer loop.
(3) Add a max name length check in afs_dir_iterate_block().
(4) Make afs_edit_dir_add() and afs_edit_dir_remove() use the function
from (1) to calculate the number of blocks rather than doing it
incorrectly themselves.
Fixes: 63a4681ff3 ("afs: Locally edit directory data for mkdir/create/unlink/...")
Fixes: ^1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Marc Dionne <marc.dionne@auristor.com>
AFS has a structured layout in its directory contents (AFS dirs are
downloaded as files and parsed locally by the client for lookup/readdir).
The slots in the directory are defined by union afs_xdr_dirent. This,
however, only directly allows a name of a length that will fit into that
union. To support a longer name, the next 1-8 contiguous entries are
annexed to the first one and the name flows across these.
afs_dir_iterate_block() uses strnlen(), limited to the space to the end of
the page, to find out how long the name is. This worked fine until
6a39e62abb. With that commit, the compiler determines the size of the
array and asserts that the string fits inside that array. This is a
problem for AFS because we *expect* it to overflow one or more arrays.
A similar problem also occurs in afs_dir_scan_block() when a directory file
is being locally edited to avoid the need to redownload it. There strlen()
was being used safely because each page has the last byte set to 0 when the
file is downloaded and validated (in afs_dir_check_page()).
Fix this by changing the afs_xdr_dirent union name field to an
indeterminate-length array and dropping the overflow field.
(Note that whilst looking at this, I realised that the calculation of the
number of slots a dirent used is non-standard and not quite right, but I'll
address that in a separate patch.)
The issue can be triggered by something like:
touch /afs/example.com/thisisaveryveryverylongname
and it generates a report that looks like:
detected buffer overflow in strnlen
------------[ cut here ]------------
kernel BUG at lib/string.c:1149!
...
RIP: 0010:fortify_panic+0xf/0x11
...
Call Trace:
afs_dir_iterate_block+0x12b/0x35b
afs_dir_iterate+0x14e/0x1ce
afs_do_lookup+0x131/0x417
afs_lookup+0x24f/0x344
lookup_open.isra.0+0x1bb/0x27d
open_last_lookups+0x166/0x237
path_openat+0xe0/0x159
do_filp_open+0x48/0xa4
? kmem_cache_alloc+0xf5/0x16e
? __clear_close_on_exec+0x13/0x22
? _raw_spin_unlock+0xa/0xb
do_sys_openat2+0x72/0xde
do_sys_open+0x3b/0x58
do_syscall_64+0x2d/0x3a
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fixes: 6a39e62abb ("lib: string.h: detect intra-object overflow in fortified string functions")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Marc Dionne <marc.dionne@auristor.com>
cc: Daniel Axtens <dja@axtens.net>
There's a memory leak in afs_parse_source() whereby multiple source=
parameters overwrite fc->source in the fs_context struct without freeing
the previously recorded source.
Fix this by only permitting a single source parameter and rejecting with
an error all subsequent ones.
This was caught by syzbot with the kernel memory leak detector, showing
something like the following trace:
unreferenced object 0xffff888114375440 (size 32):
comm "repro", pid 5168, jiffies 4294923723 (age 569.948s)
backtrace:
slab_post_alloc_hook+0x42/0x79
__kmalloc_track_caller+0x125/0x16a
kmemdup_nul+0x24/0x3c
vfs_parse_fs_string+0x5a/0xa1
generic_parse_monolithic+0x9d/0xc5
do_new_mount+0x10d/0x15a
do_mount+0x5f/0x8e
__do_sys_mount+0xff/0x127
do_syscall_64+0x2d/0x3a
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fixes: 13fcc68370 ("afs: Add fs_context support")
Reported-by: syzbot+86dc6632faaca40133ab@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When doing a lookup in a directory, the afs filesystem uses a bulk
status fetch to speculatively retrieve the statuses of up to 48 other
vnodes found in the same directory and it will then either update extant
inodes or create new ones - effectively doing 'lookup ahead'.
To avoid the possibility of deadlocking itself, however, the filesystem
doesn't lock all of those inodes; rather just the directory inode is
locked (by the VFS).
When the operation completes, afs_inode_init_from_status() or
afs_apply_status() is called, depending on whether the inode already
exists, to commit the new status.
A case exists, however, where the speculative status fetch operation may
straddle a modification operation on one of those vnodes. What can then
happen is that the speculative bulk status RPC retrieves the old status,
and whilst that is happening, the modification happens - which returns
an updated status, then the modification status is committed, then we
attempt to commit the speculative status.
This results in something like the following being seen in dmesg:
kAFS: vnode modified {100058:861} 8->9 YFS.InlineBulkStatus
showing that for vnode 861 on volume 100058, we saw YFS.InlineBulkStatus
say that the vnode had data version 8 when we'd already recorded version
9 due to a local modification. This was causing the cache to be
invalidated for that vnode when it shouldn't have been. If it happens
on a data file, this might lead to local changes being lost.
Fix this by ignoring speculative status updates if the data version
doesn't match the expected value.
Note that it is possible to get a DV regression if a volume gets
restored from a backup - but we should get a callback break in such a
case that should trigger a recheck anyway. It might be worth checking
the volume creation time in the volsync info and, if a change is
observed in that (as would happen on a restore), invalidate all caches
associated with the volume.
Fixes: 5cf9dd55a0 ("afs: Prospectively look up extra files when doing a single lookup")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When afs_write_end() is called with copied == 0, it tries to set the
dirty region, but there's no way to actually encode a 0-length region in
the encoding in page->private.
"0,0", for example, indicates a 1-byte region at offset 0. The maths
miscalculates this and sets it incorrectly.
Fix it to just do nothing but unlock and put the page in this case. We
don't actually need to mark the page dirty as nothing presumably
changed.
Fixes: 65dd2d6072 ("afs: Alter dirty range encoding in page->private")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The cleanup for the yfs_store_opaque_acl2_operation calls the wrong
function to destroy the ACL content buffer. It's an afs_acl struct, not
a yfs_acl struct - and the free function for latter may pass invalid
pointers to kfree().
Fix this by using the afs_acl_put() function. The yfs_acl_put()
function is then no longer used and can be removed.
general protection fault, probably for non-canonical address 0x7ebde00000000: 0000 [#1] SMP PTI
...
RIP: 0010:compound_head+0x0/0x11
...
Call Trace:
virt_to_cache+0x8/0x51
kfree+0x5d/0x79
yfs_free_opaque_acl+0x16/0x29
afs_put_operation+0x60/0x114
__vfs_setxattr+0x67/0x72
__vfs_setxattr_noperm+0x66/0xe9
vfs_setxattr+0x67/0xce
setxattr+0x14e/0x184
__do_sys_fsetxattr+0x66/0x8f
do_syscall_64+0x2d/0x3a
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When using the afs.yfs.acl xattr to change an AuriStor ACL, a warning
can be generated when the request is marshalled because the buffer
pointer isn't increased after adding the last element, thereby
triggering the check at the end if the ACL wasn't empty. This just
causes something like the following warning, but doesn't stop the call
from happening successfully:
kAFS: YFS.StoreOpaqueACL2: Request buffer underflow (36<108)
Fix this simply by increasing the count prior to the check.
Fixes: f5e4546347 ("afs: Implement YFS ACL setting")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The dirty region bounds stored in page->private on an afs page are 15 bits
on a 32-bit box and can, at most, represent a range of up to 32K within a
32K page with a resolution of 1 byte. This is a problem for powerpc32 with
64K pages enabled.
Further, transparent huge pages may get up to 2M, which will be a problem
for the afs filesystem on all 32-bit arches in the future.
Fix this by decreasing the resolution. For the moment, a 64K page will
have a resolution determined from PAGE_SIZE. In the future, the page will
need to be passed in to the helper functions so that the page size can be
assessed and the resolution determined dynamically.
Note that this might not be the ideal way to handle this, since it may
allow some leakage of undirtied zero bytes to the server's copy in the case
of a 3rd-party conflict. Fixing that would require a separately allocated
record and is a more complicated fix.
Fixes: 4343d00872 ("afs: Get rid of the afs_writeback record")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Fix afs_invalidatepage() to adjust the dirty region recorded in
page->private when truncating a page. If the dirty region is entirely
removed, then the private data is cleared and the page dirty state is
cleared.
Without this, if the page is truncated and then expanded again by truncate,
zeros from the expanded, but no-longer dirty region may get written back to
the server if the page gets laundered due to a conflicting 3rd-party write.
It mustn't, however, shorten the dirty region of the page if that page is
still mmapped and has been marked dirty by afs_page_mkwrite(), so a flag is
stored in page->private to record this.
Fixes: 4343d00872 ("afs: Get rid of the afs_writeback record")
Signed-off-by: David Howells <dhowells@redhat.com>
Currently, page->private on an afs page is used to store the range of
dirtied data within the page, where the range includes the lower bound, but
excludes the upper bound (e.g. 0-1 is a range covering a single byte).
This, however, requires a superfluous bit for the last-byte bound so that
on a 4KiB page, it can say 0-4096 to indicate the whole page, the idea
being that having both numbers the same would indicate an empty range.
This is unnecessary as the PG_private bit is clear if it's an empty range
(as is PG_dirty).
Alter the way the dirty range is encoded in page->private such that the
upper bound is reduced by 1 (e.g. 0-0 is then specified the same single
byte range mentioned above).
Applying this to both bounds frees up two bits, one of which can be used in
a future commit.
This allows the afs filesystem to be compiled on ppc32 with 64K pages;
without this, the following warnings are seen:
../fs/afs/internal.h: In function 'afs_page_dirty_to':
../fs/afs/internal.h:881:15: warning: right shift count >= width of type [-Wshift-count-overflow]
881 | return (priv >> __AFS_PAGE_PRIV_SHIFT) & __AFS_PAGE_PRIV_MASK;
| ^~
../fs/afs/internal.h: In function 'afs_page_dirty':
../fs/afs/internal.h:886:28: warning: left shift count >= width of type [-Wshift-count-overflow]
886 | return ((unsigned long)to << __AFS_PAGE_PRIV_SHIFT) | from;
| ^~
Fixes: 4343d00872 ("afs: Get rid of the afs_writeback record")
Signed-off-by: David Howells <dhowells@redhat.com>
The afs filesystem uses page->private to store the dirty range within a
page such that in the event of a conflicting 3rd-party write to the server,
we write back just the bits that got changed locally.
However, there are a couple of problems with this:
(1) I need a bit to note if the page might be mapped so that partial
invalidation doesn't shrink the range.
(2) There aren't necessarily sufficient bits to store the entire range of
data altered (say it's a 32-bit system with 64KiB pages or transparent
huge pages are in use).
So wrap the accesses in inline functions so that future commits can change
how this works.
Also move them out of the tracing header into the in-directory header.
There's not really any need for them to be in the tracing header.
Signed-off-by: David Howells <dhowells@redhat.com>
In afs, page->private is set to indicate the dirty region of a page. This
is done in afs_write_begin(), but that can't take account of whether the
copy into the page actually worked.
Fix this by moving the change of page->private into afs_write_end().
Fixes: 4343d00872 ("afs: Get rid of the afs_writeback record")
Signed-off-by: David Howells <dhowells@redhat.com>
Fix the leak of the target page in afs_write_begin() when it fails.
Fixes: 15b4650e55 ("afs: convert to new aops")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Nick Piggin <npiggin@gmail.com>
Fix afs to take a ref on a page when it sets PG_private on it and to drop
the ref when removing the flag.
Note that in afs_write_begin(), a lot of the time, PG_private is already
set on a page to which we're going to add some data. In such a case, we
leave the bit set and mustn't increment the page count.
As suggested by Matthew Wilcox, use attach/detach_page_private() where
possible.
Fixes: 31143d5d51 ("AFS: implement basic file write support")
Reported-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Fix afs_launder_page() to not clear PG_writeback on the page it is
laundering as the flag isn't set in this case.
Fixes: 4343d00872 ("afs: Get rid of the afs_writeback record")
Signed-off-by: David Howells <dhowells@redhat.com>
The "op" pointer is freed earlier when we call afs_put_operation().
Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Colin Ian King <colin.king@canonical.com>
The patch dca54a7bbb8c: "afs: Add tracing for cell refcount and active user
count" from Oct 13, 2020, leads to the following Smatch complaint:
fs/afs/cell.c:596 afs_unuse_cell()
warn: variable dereferenced before check 'cell' (see line 592)
Fix this by moving the retrieval of the cell debug ID to after the check of
the validity of the cell pointer.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: dca54a7bbb ("afs: Add tracing for cell refcount and active user count")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Dan Carpenter <dan.carpenter@oracle.com>
The prevention of splice-write without explicit ops made the
copy_file_write() syscall to an afs file (as done by the generic/112
xfstest) fail with EINVAL.
Fix by using iter_file_splice_write() for afs.
Fixes: 36e2c7421f ("fs: don't allow splice read/write without explicit ops")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
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Merge tag 'afs-fixes-20201016' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull afs updates from David Howells:
"A collection of fixes to fix afs_cell struct refcounting, thereby
fixing a slew of related syzbot bugs:
- Fix the cell tree in the netns to use an rwsem rather than RCU.
There seem to be some problems deriving from the use of RCU and a
seqlock to walk the rbtree, but it's not entirely clear what since
there are several different failures being seen.
Changing things to use an rwsem instead makes it more robust. The
extra performance derived from using RCU isn't necessary in this
case since the only time we're looking up a cell is during mount or
when cells are being manually added.
- Fix the refcounting by splitting the usage counter into a memory
refcount and an active users counter. The usage counter was doing
double duty, keeping track of whether a cell is still in use and
keeping track of when it needs to be destroyed - but this makes the
clean up tricky. Separating these out simplifies the logic.
- Fix purging a cell that has an alias. A cell alias pins the cell
it's an alias of, but the alias is always later in the list. Trying
to purge in a single pass causes rmmod to hang in such a case.
- Fix cell removal. If a cell's manager is requeued whilst it's
removing itself, the manager will run again and re-remove itself,
causing problems in various places. Follow Hillf Danton's
suggestion to insert a more terminal state that causes the manager
to do nothing post-removal.
In additional to the above, two other changes:
- Add a tracepoint for the cell refcount and active users count. This
helped with debugging the above and may be useful again in future.
- Downgrade an assertion to a print when a still-active server is
seen during purging. This was happening as a consequence of
incomplete cell removal before the servers were cleaned up"
* tag 'afs-fixes-20201016' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
afs: Don't assert on unpurgeable server records
afs: Add tracing for cell refcount and active user count
afs: Fix cell removal
afs: Fix cell purging with aliases
afs: Fix cell refcounting by splitting the usage counter
afs: Fix rapid cell addition/removal by not using RCU on cells tree
Don't give an assertion failure on unpurgeable afs_server records - which
kills the thread - but rather emit a trace line when we are purging a
record (which only happens during network namespace removal or rmmod) and
print a notice of the problem.
Signed-off-by: David Howells <dhowells@redhat.com>
Add a tracepoint to log the cell refcount and active user count and pass in
a reason code through various functions that manipulate these counters.
Additionally, a helper function, afs_see_cell(), is provided to log
interesting places that deal with a cell without actually doing any
accounting directly.
Signed-off-by: David Howells <dhowells@redhat.com>
When the afs module is removed, one of the things that has to be done is to
purge the cell database. afs_cell_purge() cancels the management timer and
then starts the cell manager work item to do the purging. This does a
single run through and then assumes that all cells are now purged - but
this is no longer the case.
With the introduction of alias detection, a later cell in the database can
now be holding an active count on an earlier cell (cell->alias_of). The
purge scan passes by the earlier cell first, but this can't be got rid of
until it has discarded the alias. Ordinarily, afs_unuse_cell() would
handle this by setting the management timer to trigger another pass - but
afs_set_cell_timer() doesn't do anything if the namespace is being removed
(net->live == false). rmmod then hangs in the wait on cells_outstanding in
afs_cell_purge().
Fix this by making afs_set_cell_timer() directly queue the cell manager if
net->live is false. This causes additional management passes.
Queueing the cell manager increments cells_outstanding to make sure the
wait won't complete until all cells are destroyed.
Fixes: 8a070a9648 ("afs: Detect cell aliases 1 - Cells with root volumes")
Signed-off-by: David Howells <dhowells@redhat.com>
Management of the lifetime of afs_cell struct has some problems due to the
usage counter being used to determine whether objects of that type are in
use in addition to whether anyone might be interested in the structure.
This is made trickier by cell objects being cached for a period of time in
case they're quickly reused as they hold the result of a setup process that
may be slow (DNS lookups, AFS RPC ops).
Problems include the cached root volume from alias resolution pinning its
parent cell record, rmmod occasionally hanging and occasionally producing
assertion failures.
Fix this by splitting the count of active users from the struct reference
count. Things then work as follows:
(1) The cell cache keeps +1 on the cell's activity count and this has to
be dropped before the cell can be removed. afs_manage_cell() tries to
exchange the 1 to a 0 with the cells_lock write-locked, and if
successful, the record is removed from the net->cells.
(2) One struct ref is 'owned' by the activity count. That is put when the
active count is reduced to 0 (final_destruction label).
(3) A ref can be held on a cell whilst it is queued for management on a
work queue without confusing the active count. afs_queue_cell() is
added to wrap this.
(4) The queue's ref is dropped at the end of the management. This is
split out into a separate function, afs_manage_cell_work().
(5) The root volume record is put after a cell is removed (at the
final_destruction label) rather then in the RCU destruction routine.
(6) Volumes hold struct refs, but aren't active users.
(7) Both counts are displayed in /proc/net/afs/cells.
There are some management function changes:
(*) afs_put_cell() now just decrements the refcount and triggers the RCU
destruction if it becomes 0. It no longer sets a timer to have the
manager do this.
(*) afs_use_cell() and afs_unuse_cell() are added to increase and decrease
the active count. afs_unuse_cell() sets the management timer.
(*) afs_queue_cell() is added to queue a cell with approprate refs.
There are also some other fixes:
(*) Don't let /proc/net/afs/cells access a cell's vllist if it's NULL.
(*) Make sure that candidate cells in lookups are properly destroyed
rather than being simply kfree'd. This ensures the bits it points to
are destroyed also.
(*) afs_dec_cells_outstanding() is now called in cell destruction rather
than at "final_destruction". This ensures that cell->net is still
valid to the end of the destructor.
(*) As a consequence of the previous two changes, move the increment of
net->cells_outstanding that was at the point of insertion into the
tree to the allocation routine to correctly balance things.
Fixes: 989782dcdc ("afs: Overhaul cell database management")
Signed-off-by: David Howells <dhowells@redhat.com>
There are a number of problems that are being seen by the rapidly mounting
and unmounting an afs dynamic root with an explicit cell and volume
specified (which should probably be rejected, but that's a separate issue):
What the tests are doing is to look up/create a cell record for the name
given and then tear it down again without actually using it to try to talk
to a server. This is repeated endlessly, very fast, and the new cell
collides with the old one if it's not quick enough to reuse it.
It appears (as suggested by Hillf Danton) that the search through the RB
tree under a read_seqbegin_or_lock() under RCU conditions isn't safe and
that it's not blocking the write_seqlock(), despite taking two passes at
it. He suggested that the code should take a ref on the cell it's
attempting to look at - but this shouldn't be necessary until we've
compared the cell names. It's possible that I'm missing a barrier
somewhere.
However, using an RCU search for this is overkill, really - we only need to
access the cell name in a few places, and they're places where we're may
end up sleeping anyway.
Fix this by switching to an R/W semaphore instead.
Additionally, draw the down_read() call inside the function (renamed to
afs_find_cell()) since all the callers were taking the RCU read lock (or
should've been[*]).
[*] afs_probe_cell_name() should have been, but that doesn't appear to be
involved in the bug reports.
The symptoms of this look like:
general protection fault, probably for non-canonical address 0xf27d208691691fdb: 0000 [#1] PREEMPT SMP KASAN
KASAN: maybe wild-memory-access in range [0x93e924348b48fed8-0x93e924348b48fedf]
...
RIP: 0010:strncasecmp lib/string.c:52 [inline]
RIP: 0010:strncasecmp+0x5f/0x240 lib/string.c:43
afs_lookup_cell_rcu+0x313/0x720 fs/afs/cell.c:88
afs_lookup_cell+0x2ee/0x1440 fs/afs/cell.c:249
afs_parse_source fs/afs/super.c:290 [inline]
...
Fixes: 989782dcdc ("afs: Overhaul cell database management")
Reported-by: syzbot+459a5dce0b4cb70fd076@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Hillf Danton <hdanton@sina.com>
cc: syzkaller-bugs@googlegroups.com
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Merge tag 'block-5.10-2020-10-12' of git://git.kernel.dk/linux-block
Pull block updates from Jens Axboe:
- Series of merge handling cleanups (Baolin, Christoph)
- Series of blk-throttle fixes and cleanups (Baolin)
- Series cleaning up BDI, seperating the block device from the
backing_dev_info (Christoph)
- Removal of bdget() as a generic API (Christoph)
- Removal of blkdev_get() as a generic API (Christoph)
- Cleanup of is-partition checks (Christoph)
- Series reworking disk revalidation (Christoph)
- Series cleaning up bio flags (Christoph)
- bio crypt fixes (Eric)
- IO stats inflight tweak (Gabriel)
- blk-mq tags fixes (Hannes)
- Buffer invalidation fixes (Jan)
- Allow soft limits for zone append (Johannes)
- Shared tag set improvements (John, Kashyap)
- Allow IOPRIO_CLASS_RT for CAP_SYS_NICE (Khazhismel)
- DM no-wait support (Mike, Konstantin)
- Request allocation improvements (Ming)
- Allow md/dm/bcache to use IO stat helpers (Song)
- Series improving blk-iocost (Tejun)
- Various cleanups (Geert, Damien, Danny, Julia, Tetsuo, Tian, Wang,
Xianting, Yang, Yufen, yangerkun)
* tag 'block-5.10-2020-10-12' of git://git.kernel.dk/linux-block: (191 commits)
block: fix uapi blkzoned.h comments
blk-mq: move cancel of hctx->run_work to the front of blk_exit_queue
blk-mq: get rid of the dead flush handle code path
block: get rid of unnecessary local variable
block: fix comment and add lockdep assert
blk-mq: use helper function to test hw stopped
block: use helper function to test queue register
block: remove redundant mq check
block: invoke blk_mq_exit_sched no matter whether have .exit_sched
percpu_ref: don't refer to ref->data if it isn't allocated
block: ratelimit handle_bad_sector() message
blk-throttle: Re-use the throtl_set_slice_end()
blk-throttle: Open code __throtl_de/enqueue_tg()
blk-throttle: Move service tree validation out of the throtl_rb_first()
blk-throttle: Move the list operation after list validation
blk-throttle: Fix IO hang for a corner case
blk-throttle: Avoid tracking latency if low limit is invalid
blk-throttle: Avoid getting the current time if tg->last_finish_time is 0
blk-throttle: Remove a meaningless parameter for throtl_downgrade_state()
block: Remove redundant 'return' statement
...
The afs filesystem has a lock[*] that it uses to serialise I/O operations
going to the server (vnode->io_lock), as the server will only perform one
modification operation at a time on any given file or directory. This
prevents the the filesystem from filling up all the call slots to a server
with calls that aren't going to be executed in parallel anyway, thereby
allowing operations on other files to obtain slots.
[*] Note that is probably redundant for directories at least since
i_rwsem is used to serialise directory modifications and
lookup/reading vs modification. The server does allow parallel
non-modification ops, however.
When a file truncation op completes, we truncate the in-memory copy of the
file to match - but we do it whilst still holding the io_lock, the idea
being to prevent races with other operations.
However, if writeback starts in a worker thread simultaneously with
truncation (whilst notify_change() is called with i_rwsem locked, writeback
pays it no heed), it may manage to set PG_writeback bits on the pages that
will get truncated before afs_setattr_success() manages to call
truncate_pagecache(). Truncate will then wait for those pages - whilst
still inside io_lock:
# cat /proc/8837/stack
[<0>] wait_on_page_bit_common+0x184/0x1e7
[<0>] truncate_inode_pages_range+0x37f/0x3eb
[<0>] truncate_pagecache+0x3c/0x53
[<0>] afs_setattr_success+0x4d/0x6e
[<0>] afs_wait_for_operation+0xd8/0x169
[<0>] afs_do_sync_operation+0x16/0x1f
[<0>] afs_setattr+0x1fb/0x25d
[<0>] notify_change+0x2cf/0x3c4
[<0>] do_truncate+0x7f/0xb2
[<0>] do_sys_ftruncate+0xd1/0x104
[<0>] do_syscall_64+0x2d/0x3a
[<0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
The writeback operation, however, stalls indefinitely because it needs to
get the io_lock to proceed:
# cat /proc/5940/stack
[<0>] afs_get_io_locks+0x58/0x1ae
[<0>] afs_begin_vnode_operation+0xc7/0xd1
[<0>] afs_store_data+0x1b2/0x2a3
[<0>] afs_write_back_from_locked_page+0x418/0x57c
[<0>] afs_writepages_region+0x196/0x224
[<0>] afs_writepages+0x74/0x156
[<0>] do_writepages+0x2d/0x56
[<0>] __writeback_single_inode+0x84/0x207
[<0>] writeback_sb_inodes+0x238/0x3cf
[<0>] __writeback_inodes_wb+0x68/0x9f
[<0>] wb_writeback+0x145/0x26c
[<0>] wb_do_writeback+0x16a/0x194
[<0>] wb_workfn+0x74/0x177
[<0>] process_one_work+0x174/0x264
[<0>] worker_thread+0x117/0x1b9
[<0>] kthread+0xec/0xf1
[<0>] ret_from_fork+0x1f/0x30
and thus deadlock has occurred.
Note that whilst afs_setattr() calls filemap_write_and_wait(), the fact
that the caller is holding i_rwsem doesn't preclude more pages being
dirtied through an mmap'd region.
Fix this by:
(1) Use the vnode validate_lock to mediate access between afs_setattr()
and afs_writepages():
(a) Exclusively lock validate_lock in afs_setattr() around the whole
RPC operation.
(b) If WB_SYNC_ALL isn't set on entry to afs_writepages(), trying to
shared-lock validate_lock and returning immediately if we couldn't
get it.
(c) If WB_SYNC_ALL is set, wait for the lock.
The validate_lock is also used to validate a file and to zap its cache
if the file was altered by a third party, so it's probably a good fit
for this.
(2) Move the truncation outside of the io_lock in setattr, using the same
hook as is used for local directory editing.
This requires the old i_size to be retained in the operation record as
we commit the revised status to the inode members inside the io_lock
still, but we still need to know if we reduced the file size.
Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Set up a readahead size by default, as very few users have a good
reason to change it. This means code, ecryptfs, and orangefs now
set up the values while they were previously missing it, while ubifs,
mtd and vboxsf manually set it to 0 to avoid readahead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: David Sterba <dsterba@suse.com> [btrfs]
Acked-by: Richard Weinberger <richard@nod.at> [ubifs, mtd]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull networking fixes from David Miller:
1) Use netif_rx_ni() when necessary in batman-adv stack, from Jussi
Kivilinna.
2) Fix loss of RTT samples in rxrpc, from David Howells.
3) Memory leak in hns_nic_dev_probe(), from Dignhao Liu.
4) ravb module cannot be unloaded, fix from Yuusuke Ashizuka.
5) We disable BH for too lokng in sctp_get_port_local(), add a
cond_resched() here as well, from Xin Long.
6) Fix memory leak in st95hf_in_send_cmd, from Dinghao Liu.
7) Out of bound access in bpf_raw_tp_link_fill_link_info(), from
Yonghong Song.
8) Missing of_node_put() in mt7530 DSA driver, from Sumera
Priyadarsini.
9) Fix crash in bnxt_fw_reset_task(), from Michael Chan.
10) Fix geneve tunnel checksumming bug in hns3, from Yi Li.
11) Memory leak in rxkad_verify_response, from Dinghao Liu.
12) In tipc, don't use smp_processor_id() in preemptible context. From
Tuong Lien.
13) Fix signedness issue in mlx4 memory allocation, from Shung-Hsi Yu.
14) Missing clk_disable_prepare() in gemini driver, from Dan Carpenter.
15) Fix ABI mismatch between driver and firmware in nfp, from Louis
Peens.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (110 commits)
net/smc: fix sock refcounting in case of termination
net/smc: reset sndbuf_desc if freed
net/smc: set rx_off for SMCR explicitly
net/smc: fix toleration of fake add_link messages
tg3: Fix soft lockup when tg3_reset_task() fails.
doc: net: dsa: Fix typo in config code sample
net: dp83867: Fix WoL SecureOn password
nfp: flower: fix ABI mismatch between driver and firmware
tipc: fix shutdown() of connectionless socket
ipv6: Fix sysctl max for fib_multipath_hash_policy
drivers/net/wan/hdlc: Change the default of hard_header_len to 0
net: gemini: Fix another missing clk_disable_unprepare() in probe
net: bcmgenet: fix mask check in bcmgenet_validate_flow()
amd-xgbe: Add support for new port mode
net: usb: dm9601: Add USB ID of Keenetic Plus DSL
vhost: fix typo in error message
net: ethernet: mlx4: Fix memory allocation in mlx4_buddy_init()
pktgen: fix error message with wrong function name
net: ethernet: ti: am65-cpsw: fix rmii 100Mbit link mode
cxgb4: fix thermal zone device registration
...
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Merge tag 'rxrpc-fixes-20200820' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
David Howells says:
====================
rxrpc, afs: Fix probing issues
Here are some fixes for rxrpc and afs to fix issues in the RTT measuring in
rxrpc and thence the Volume Location server probing in afs:
(1) Move the serial number of a received ACK into a local variable to
simplify the next patch.
(2) Fix the loss of RTT samples due to extra interposed ACKs causing
baseline information to be discarded too early. This is a particular
problem for afs when it sends a single very short call to probe a
server it hasn't talked to recently.
(3) Fix rxrpc_kernel_get_srtt() to indicate whether it actually has seen
any valid samples or not.
(4) Remove a field that's set/woken, but never read/waited on.
(5) Expose the RTT and other probe information through procfs to make
debugging of this stuff easier.
(6) Fix VL rotation in afs to only use summary information from VL probing
and not the probe running state (which gets clobbered when next a
probe is issued).
(7) Fix VL rotation to actually return the error aggregated from the probe
errors.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The fall through annotation comes after a return statement so it's not
reachable.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
If an error occurs during the construction of an afs superblock, it's
possible that an error occurs after a superblock is created, but before
we've created the root dentry. If the superblock has a dynamic root
(ie. what's normally mounted on /afs), the afs_kill_super() will call
afs_dynroot_depopulate() to unpin any created dentries - but this will
oops if the root hasn't been created yet.
Fix this by skipping that bit of code if there is no root dentry.
This leads to an oops looking like:
general protection fault, ...
KASAN: null-ptr-deref in range [0x0000000000000068-0x000000000000006f]
...
RIP: 0010:afs_dynroot_depopulate+0x25f/0x529 fs/afs/dynroot.c:385
...
Call Trace:
afs_kill_super+0x13b/0x180 fs/afs/super.c:535
deactivate_locked_super+0x94/0x160 fs/super.c:335
afs_get_tree+0x1124/0x1460 fs/afs/super.c:598
vfs_get_tree+0x89/0x2f0 fs/super.c:1547
do_new_mount fs/namespace.c:2875 [inline]
path_mount+0x1387/0x2070 fs/namespace.c:3192
do_mount fs/namespace.c:3205 [inline]
__do_sys_mount fs/namespace.c:3413 [inline]
__se_sys_mount fs/namespace.c:3390 [inline]
__x64_sys_mount+0x27f/0x300 fs/namespace.c:3390
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
which is oopsing on this line:
inode_lock(root->d_inode);
presumably because sb->s_root was NULL.
Fixes: 0da0b7fd73 ("afs: Display manually added cells in dynamic root mount")
Reported-by: syzbot+c1eff8205244ae7e11a6@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The afs_put_operation() function needs to put the reference to the key
that's authenticating the operation.
Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Reported-by: Dave Botsch <botsch@cnf.cornell.edu>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The error handling in the VL server rotation in the case of there being no
contactable servers is not correct. In such a case, the records of all the
servers in the list are scanned and the errors and abort codes are mapped
and prioritised and one error is chosen. This is then forgotten and the
default error is used (EDESTADDRREQ).
Fix this by using the calculated error.
Also we need to note whether a server responded on one of its endpoints so
that we can priorise an error from an abort message over local and network
errors.
Fixes: 4584ae96ae ("afs: Fix missing net error handling")
Signed-off-by: David Howells <dhowells@redhat.com>
Don't use the running state for VL server probes to make decisions about
which server to use as the state is cleared at the start of a probe and
intermediate values might also be misleading.
Instead, add a separate 'latest known' rtt in the afs_vlserver struct and a
flag to indicate if the server is known to be responding and update these
as and when we know what to change them to.
Fixes: 3bf0fb6f33 ("afs: Probe multiple fileservers simultaneously")
Signed-off-by: David Howells <dhowells@redhat.com>
Convert various bitfields in afs_vlserver::probe to a mask and then expose
this and some other bits of information through /proc/net/afs/<cell>/vlservers
to make it easier to debug VL server communication issues.
Signed-off-by: David Howells <dhowells@redhat.com>
Fix rxrpc_kernel_get_srtt() to indicate the validity of the returned
smoothed RTT. If we haven't had any valid samples yet, the SRTT isn't
useful.
Fixes: c410bf0193 ("rxrpc: Fix the excessive initial retransmission timeout")
Signed-off-by: David Howells <dhowells@redhat.com>
Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.
In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:
git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
xargs perl -pi -e \
's/\buninitialized_var\(([^\)]+)\)/\1/g;
s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'
drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.
No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.
[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/
Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB
Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers
Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs
Signed-off-by: Kees Cook <keescook@chromium.org>
The afs filesystem driver allows unstarted operations to be cancelled by
signal, but most of these can easily be restarted (mkdir for example). The
primary culprits for reproducing this are those applications that use
SIGALRM to display a progress counter.
File lock-extension operation is marked uninterruptible as we have a
limited time in which to do it, and the release op is marked
uninterruptible also as if we fail to unlock a file, we'll have to wait 20
mins before anyone can lock it again.
The store operation logs a warning if it gets interruption, e.g.:
kAFS: Unexpected error from FS.StoreData -4
because it's run from the background - but it can also be run from
fdatasync()-type things. However, store options aren't marked
interruptible at the moment.
Fix this in the following ways:
(1) Mark store operations as uninterruptible. It might make sense to
relax this for certain situations, but I'm not sure how to make sure
that background store ops aren't affected by signals to foreground
processes that happen to trigger them.
(2) In afs_get_io_locks(), where we're getting the serialisation lock for
talking to the fileserver, return ERESTARTSYS rather than EINTR
because a lot of the operations (e.g. mkdir) are restartable if we
haven't yet started sending the op to the server.
Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The cell name stored in the afs_cell struct is a 64-char + NUL buffer -
when it needs to be able to handle up to AFS_MAXCELLNAME (256 chars) + NUL.
Fix this by changing the array to a pointer and allocating the string.
Found using Coverity.
Fixes: 989782dcdc ("afs: Overhaul cell database management")
Reported-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The fileserver probe timer, net->fs_probe_timer, isn't cancelled when
the kafs module is being removed and so the count it holds on
net->servers_outstanding doesn't get dropped..
This causes rmmod to wait forever. The hung process shows a stack like:
afs_purge_servers+0x1b5/0x23c [kafs]
afs_net_exit+0x44/0x6e [kafs]
ops_exit_list+0x72/0x93
unregister_pernet_operations+0x14c/0x1ba
unregister_pernet_subsys+0x1d/0x2a
afs_exit+0x29/0x6f [kafs]
__do_sys_delete_module.isra.0+0x1a2/0x24b
do_syscall_64+0x51/0x95
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fix this by:
(1) Attempting to cancel the probe timer and, if successful, drop the
count that the timer was holding.
(2) Make the timer function just drop the count and not schedule the
prober if the afs portion of net namespace is being destroyed.
Also, whilst we're at it, make the following changes:
(3) Initialise net->servers_outstanding to 1 and decrement it before
waiting on it so that it doesn't generate wake up events by being
decremented to 0 until we're cleaning up.
(4) Switch the atomic_dec() on ->servers_outstanding for ->fs_timer in
afs_purge_servers() to use the helper function for that.
Fixes: f6cbb368bc ("afs: Actively poll fileservers to maintain NAT or firewall openings")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix afs_do_lookup()'s fallback case for when FS.InlineBulkStatus isn't
supported by the server.
In the fallback, it calls FS.FetchStatus for the specific vnode it's
meant to be looking up. Commit b6489a49f7 broke this by renaming one
of the two identically-named afs_fetch_status_operation descriptors to
something else so that one of them could be made non-static. The site
that used the renamed one, however, wasn't renamed and didn't produce
any warning because the other was declared in a header.
Fix this by making afs_do_lookup() use the renamed variant.
Note that there are two variants of the success method because one is
called from ->lookup() where we may or may not have an inode, but can't
call iget until after we've talked to the server - whereas the other is
called from within iget where we have an inode, but it may or may not be
initialised.
The latter variant expects there to be an inode, but because it's being
called from there former case, there might not be - resulting in an oops
like the following:
BUG: kernel NULL pointer dereference, address: 00000000000000b0
...
RIP: 0010:afs_fetch_status_success+0x27/0x7e
...
Call Trace:
afs_wait_for_operation+0xda/0x234
afs_do_lookup+0x2fe/0x3c1
afs_lookup+0x3c5/0x4bd
__lookup_slow+0xcd/0x10f
walk_component+0xa2/0x10c
path_lookupat.isra.0+0x80/0x110
filename_lookup+0x81/0x104
vfs_statx+0x76/0x109
__do_sys_newlstat+0x39/0x6b
do_syscall_64+0x4c/0x78
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fixes: b6489a49f7 ("afs: Fix silly rename")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix AFS's silly rename by the following means:
(1) Set the destination directory in afs_do_silly_rename() so as to avoid
misbehaviour and indicate that the directory data version will
increment by 1 so as to avoid warnings about unexpected changes in the
DV. Also indicate that the ctime should be updated to avoid xfstest
grumbling.
(2) Note when the server indicates that a directory changed more than we
expected (AFS_OPERATION_DIR_CONFLICT), indicating a conflict with a
third party change, checking on successful completion of unlink and
rename.
The problem is that the FS.RemoveFile RPC op doesn't report the status
of the unlinked file, though YFS.RemoveFile2 does. This can be
mitigated by the assumption that if the directory DV cranked by
exactly 1, we can be sure we removed one link from the file; further,
ordinarily in AFS, files cannot be hardlinked across directories, so
if we reduce nlink to 0, the file is deleted.
However, if the directory DV jumps by more than 1, we cannot know if a
third party intervened by adding or removing a link on the file we
just removed a link from.
The same also goes for any vnode that is at the destination of the
FS.Rename RPC op.
(3) Make afs_vnode_commit_status() apply the nlink drop inside the cb_lock
section along with the other attribute updates if ->op_unlinked is set
on the descriptor for the appropriate vnode.
(4) Issue a follow up status fetch to the unlinked file in the event of a
third party conflict that makes it impossible for us to know if we
actually deleted the file or not.
(5) Provide a flag, AFS_VNODE_SILLY_DELETED, to make afs_getattr() lie to
the user about the nlink of a silly deleted file so that it appears as
0, not 1.
Found with the generic/035 and generic/084 xfstests.
Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
afs_vnode_commit_status() is only ever called if op->error is 0, so remove
the op->error checks from the function.
Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Signed-off-by: David Howells <dhowells@redhat.com>
afs_check_for_remote_deletion() checks to see if error ENOENT is returned
by the server in response to an operation and, if so, marks the primary
vnode as having been deleted as the FID is no longer valid.
However, it's being called from the operation success functions, where no
abort has happened - and if an inline abort is recorded, it's handled by
afs_vnode_commit_status().
Fix this by actually calling the operation aborted method if provided and
having that point to afs_check_for_remote_deletion().
Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Signed-off-by: David Howells <dhowells@redhat.com>
Fix yfs_fs_fetch_status() to honour the vnode selector in
op->fetch_status.which as does afs_fs_fetch_status() that allows
afs_do_lookup() to use this as an alternative to the InlineBulkStatus RPC
call if not implemented by the server.
This doesn't matter in the current code as YFS servers always implement
InlineBulkStatus, but a subsequent will call it on YFS servers too in some
circumstances.
Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Signed-off-by: David Howells <dhowells@redhat.com>
Abort code UAEOVERFLOW is returned when we try and set a time that's out of
range, but it's currently mapped to EREMOTEIO by the default case.
Fix UAEOVERFLOW to map instead to EOVERFLOW.
Found with the generic/258 xfstest. Note that the test is wrong as it
assumes that the filesystem will support a pre-UNIX-epoch date.
Fixes: 1eda8bab70 ("afs: Add support for the UAE error table")
Signed-off-by: David Howells <dhowells@redhat.com>
Fix the following issues:
(1) Fix writeback to reduce the size of a store operation to i_size,
effectively discarding the extra data.
The problem comes when afs_page_mkwrite() records that a page is about
to be modified by mmap(). It doesn't know what bits of the page are
going to be modified, so it records the whole page as being dirty
(this is stored in page->private as start and end offsets).
Without this, the marshalling for the store to the server extends the
size of the file to the end of the page (in afs_fs_store_data() and
yfs_fs_store_data()).
(2) Fix setattr to actually truncate the pagecache, thereby clearing
the discarded part of a file.
(3) Fix setattr to check that the new size is okay and to disable
ATTR_SIZE if i_size wouldn't change.
(4) Force i_size to be updated as the result of a truncate.
(5) Don't truncate if ATTR_SIZE is not set.
(6) Call pagecache_isize_extended() if the file was enlarged.
Note that truncate_set_size() isn't used because the setting of i_size is
done inside afs_vnode_commit_status() under the vnode->cb_lock.
Found with the generic/029 and generic/393 xfstests.
Fixes: 31143d5d51 ("AFS: implement basic file write support")
Fixes: 4343d00872 ("afs: Get rid of the afs_writeback record")
Signed-off-by: David Howells <dhowells@redhat.com>
The in-kernel afs filesystem ignores ctime because the AFS fileserver
protocol doesn't support ctimes. This, however, causes various xfstests to
fail.
Work around this by:
(1) Setting ctime to attr->ia_ctime in afs_setattr().
(2) Not ignoring ATTR_MTIME_SET, ATTR_TIMES_SET and ATTR_TOUCH settings.
(3) Setting the ctime from the server mtime when on the target file when
creating a hard link to it.
(4) Setting the ctime on directories from their revised mtimes when
renaming/moving a file.
Found by the generic/221 and generic/309 xfstests.
Signed-off-by: David Howells <dhowells@redhat.com>
When doing a partial writeback, afs_write_back_from_locked_page() may
generate an FS.StoreData RPC request that writes out part of a file when a
file has been constructed from pieces by doing seek, write, seek, write,
... as is done by ld.
The FS.StoreData RPC is given the current i_size as the file length, but
the server basically ignores it unless the data length is 0 (in which case
it's just a truncate operation). The revised file length returned in the
result of the RPC may then not reflect what we suggested - and this leads
to i_size getting moved backwards - which causes issues later.
Fix the client to take account of this by ignoring the returned file size
unless the data version number jumped unexpectedly - in which case we're
going to have to clear the pagecache and reload anyway.
This can be observed when doing a kernel build on an AFS mount. The
following pair of commands produce the issue:
ld -m elf_x86_64 -z max-page-size=0x200000 --emit-relocs \
-T arch/x86/realmode/rm/realmode.lds \
arch/x86/realmode/rm/header.o \
arch/x86/realmode/rm/trampoline_64.o \
arch/x86/realmode/rm/stack.o \
arch/x86/realmode/rm/reboot.o \
-o arch/x86/realmode/rm/realmode.elf
arch/x86/tools/relocs --realmode \
arch/x86/realmode/rm/realmode.elf \
>arch/x86/realmode/rm/realmode.relocs
This results in the latter giving:
Cannot read ELF section headers 0/18: Success
as the realmode.elf file got corrupted.
The sequence of events can also be driven with:
xfs_io -t -f \
-c "pwrite -S 0x58 0 0x58" \
-c "pwrite -S 0x59 10000 1000" \
-c "close" \
/afs/example.com/scratch/a
Fixes: 31143d5d51 ("AFS: implement basic file write support")
Signed-off-by: David Howells <dhowells@redhat.com>
Fix afs_write_end() to change i_size under vnode->cb_lock rather than
->wb_lock so that it doesn't race with afs_vnode_commit_status() and
afs_getattr().
The ->wb_lock is only meant to guard access to ->wb_keys which isn't
accessed by that piece of code.
Fixes: 4343d00872 ("afs: Get rid of the afs_writeback record")
Signed-off-by: David Howells <dhowells@redhat.com>
The mtime on an inode needs to be updated when a write is made into an
mmap'ed section. There are three ways in which this could be done: update
it when page_mkwrite is called, update it when a page is changed from dirty
to writeback or leave it to the server and fix the mtime up from the reply
to the StoreData RPC.
Found with the generic/215 xfstest.
Fixes: 1cf7a1518a ("afs: Implement shared-writeable mmap")
Signed-off-by: David Howells <dhowells@redhat.com>
Fix afs_store_data() so that it sets the mtime in the new operation
descriptor otherwise the mtime on the server gets set to 0 when a write is
stored to the server.
Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Reported-by: Dave Botsch <botsch@cnf.cornell.edu>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix a couple of %px to be %p in debugging statements.
Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Fixes: 8a070a9648 ("afs: Detect cell aliases 1 - Cells with root volumes")
Reported-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Fix afs_compare_addrs() to use WARN_ON(1) instead of BUG() and return 1
(ie. srx_a > srx_b).
There's no point trying to put actual error handling in as this should not
occur unless a new transport address type is allowed by AFS. And even if
it does, in this particular case, it'll just never match unknown types of
addresses. This BUG() was more of a 'you need to add a case here'
indicator.
Reported-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Fix AFS file locking to use the correct vnode pointer and remove a member
of the afs_operation struct that is never set, but it is read and followed,
causing an oops.
This can be triggered by:
flock -s /afs/example.com/foo sleep 1
when it calls the kernel to get a file lock.
Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Reported-by: Dave Botsch <botsch@cnf.cornell.edu>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Dave Botsch <botsch@cnf.cornell.edu>
Fix afs_put_sysnames() to actually free the specified afs_sysnames
object after its reference count has been decreased to zero and
its contents have been released.
Fixes: 6f8880d8e6 ("afs: Implement @sys substitution handling")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: David Howells <dhowells@redhat.com>
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Merge tag 'afs-next-20200604' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull AFS updates from David Howells:
"There's some core VFS changes which affect a couple of filesystems:
- Make the inode hash table RCU safe and providing some RCU-safe
accessor functions. The search can then be done without taking the
inode_hash_lock. Care must be taken because the object may be being
deleted and no wait is made.
- Allow iunique() to avoid taking the inode_hash_lock.
- Allow AFS's callback processing to avoid taking the inode_hash_lock
when using the inode table to find an inode to notify.
- Improve Ext4's time updating. Konstantin Khlebnikov said "For now,
I've plugged this issue with try-lock in ext4 lazy time update.
This solution is much better."
Then there's a set of changes to make a number of improvements to the
AFS driver:
- Improve callback (ie. third party change notification) processing
by:
(a) Relying more on the fact we're doing this under RCU and by
using fewer locks. This makes use of the RCU-based inode
searching outlined above.
(b) Moving to keeping volumes in a tree indexed by volume ID
rather than a flat list.
(c) Making the server and volume records logically part of the
cell. This means that a server record now points directly at
the cell and the tree of volumes is there. This removes an N:M
mapping table, simplifying things.
- Improve keeping NAT or firewall channels open for the server
callbacks to reach the client by actively polling the fileserver on
a timed basis, instead of only doing it when we have an operation
to process.
- Improving detection of delayed or lost callbacks by including the
parent directory in the list of file IDs to be queried when doing a
bulk status fetch from lookup. We can then check to see if our copy
of the directory has changed under us without us getting notified.
- Determine aliasing of cells (such as a cell that is pointed to be a
DNS alias). This allows us to avoid having ambiguity due to
apparently different cells using the same volume and file servers.
- Improve the fileserver rotation to do more probing when it detects
that all of the addresses to a server are listed as non-responsive.
It's possible that an address that previously stopped responding
has become responsive again.
Beyond that, lay some foundations for making some calls asynchronous:
- Turn the fileserver cursor struct into a general operation struct
and hang the parameters off of that rather than keeping them in
local variables and hang results off of that rather than the call
struct.
- Implement some general operation handling code and simplify the
callers of operations that affect a volume or a volume component
(such as a file). Most of the operation is now done by core code.
- Operations are supplied with a table of operations to issue
different variants of RPCs and to manage the completion, where all
the required data is held in the operation object, thereby allowing
these to be called from a workqueue.
- Put the standard "if (begin), while(select), call op, end" sequence
into a canned function that just emulates the current behaviour for
now.
There are also some fixes interspersed:
- Don't let the EACCES from ICMP6 mapping reach the user as such,
since it's confusing as to whether it's a filesystem error. Convert
it to EHOSTUNREACH.
- Don't use the epoch value acquired through probing a server. If we
have two servers with the same UUID but in different cells, it's
hard to draw conclusions from them having different epoch values.
- Don't interpret the argument to the CB.ProbeUuid RPC as a
fileserver UUID and look up a fileserver from it.
- Deal with servers in different cells having the same UUIDs. In the
event that a CB.InitCallBackState3 RPC is received, we have to
break the callback promises for every server record matching that
UUID.
- Don't let afs_statfs return values that go below 0.
- Don't use running fileserver probe state to make server selection
and address selection decisions on. Only make decisions on final
state as the running state is cleared at the start of probing"
Acked-by: Al Viro <viro@zeniv.linux.org.uk> (fs/inode.c part)
* tag 'afs-next-20200604' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: (27 commits)
afs: Adjust the fileserver rotation algorithm to reprobe/retry more quickly
afs: Show more a bit more server state in /proc/net/afs/servers
afs: Don't use probe running state to make decisions outside probe code
afs: Fix afs_statfs() to not let the values go below zero
afs: Fix the by-UUID server tree to allow servers with the same UUID
afs: Reorganise volume and server trees to be rooted on the cell
afs: Add a tracepoint to track the lifetime of the afs_volume struct
afs: Detect cell aliases 3 - YFS Cells with a canonical cell name op
afs: Detect cell aliases 2 - Cells with no root volumes
afs: Detect cell aliases 1 - Cells with root volumes
afs: Implement client support for the YFSVL.GetCellName RPC op
afs: Retain more of the VLDB record for alias detection
afs: Fix handling of CB.ProbeUuid cache manager op
afs: Don't get epoch from a server because it may be ambiguous
afs: Build an abstraction around an "operation" concept
afs: Rename struct afs_fs_cursor to afs_operation
afs: Remove the error argument from afs_protocol_error()
afs: Set error flag rather than return error from file status decode
afs: Make callback processing more efficient.
afs: Show more information in /proc/net/afs/servers
...
Adjust the fileserver rotation algorithm so that if we've tried all the
addresses on a server (cumulatively over multiple operations) until we've
run out of untried addresses, immediately reprobe all that server's
interfaces and retry the op at least once before we move onto the next
server.
Signed-off-by: David Howells <dhowells@redhat.com>
Display more information about the state of a server record, including the
flags, rtt and break counter plus the probe state for each server in
/proc/net/afs/servers.
Rearrange the server flags a bit to make them easier to read at a glance in
the proc file.
Signed-off-by: David Howells <dhowells@redhat.com>
Don't use the running state for fileserver probes to make decisions about
which server to use as the state is cleared at the start of a probe and
also intermediate values might be misleading.
Instead, add a separate 'latest known' rtt in the afs_server struct and a
flag to indicate if the server is known to be responding and update these
as and when we know what to change them to.
Signed-off-by: David Howells <dhowells@redhat.com>
Fix afs_statfs() so that the value for f_bavail and f_bfree don't go
"negative" if the number of blocks in use by a volume exceeds the max quota
for that volume.
Signed-off-by: David Howells <dhowells@redhat.com>
Whilst it shouldn't happen, it is possible for multiple fileservers to
share a UUID, particularly if an entire cell has been duplicated, UUIDs and
all. In such a case, it's not necessarily possible to map the effect of
the CB.InitCallBackState3 incoming RPC to a specific server unambiguously
by UUID and thus to a specific cell.
Indeed, there's a problem whereby multiple server records may need to
occupy the same spot in the rb_tree rooted in the afs_net struct.
Fix this by allowing servers to form a list, with the head of the list in
the tree. When the front entry in the list is removed, the second in the
list just replaces it. afs_init_callback_state() then just goes down the
line, poking each server in the list.
This means that some servers will be unnecessarily poked, unfortunately.
An alternative would be to route by call parameters.
Reported-by: Jeffrey Altman <jaltman@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Reorganise afs_volume objects such that they're in a tree keyed on volume
ID, rooted at on an afs_cell object rather than being in multiple trees,
each of which is rooted on an afs_server object.
afs_server structs become per-cell and acquire a pointer to the cell.
The process of breaking a callback then starts with finding the server by
its network address, following that to the cell and then looking up each
volume ID in the volume tree.
This is simpler than the afs_vol_interest/afs_cb_interest N:M mapping web
and allows those structs and the code for maintaining them to be simplified
or removed.
It does make a couple of things a bit more tricky, though:
(1) Operations now start with a volume, not a server, so there can be more
than one answer as to whether or not the server we'll end up using
supports the FS.InlineBulkStatus RPC.
(2) CB RPC operations that specify the server UUID. There's still a tree
of servers by UUID on the afs_net struct, but the UUIDs in it aren't
guaranteed unique.
Signed-off-by: David Howells <dhowells@redhat.com>
YFS Volume Location servers have an operation by which the cell name may be
queried. Use this to find out what a YFS server thinks the canonical cell
name should be.
Signed-off-by: David Howells <dhowells@redhat.com>
Implement the second phase of cell alias detection. This part handles
alias detection for cells that don't have root.cell volumes and so we have
to find some other volume or fileserver to query.
We take the first volume from each such cell and attempt to look it up in
the new cell. If found, we compare the records, if they are the same, we
judge the cell names to be aliases.
Signed-off-by: David Howells <dhowells@redhat.com>
Put in the first phase of cell alias detection. This part handles alias
detection for cells that have root.cell volumes (which is expected to be
likely).
When a cell becomes newly active, it is probed for its root.cell volume,
and if it has one, this volume is compared against other root.cell volumes
to find out if the list of fileserver UUIDs have any in common - and if
that's the case, do the address lists of those fileservers have any
addresses in common. If they do, the new cell is adjudged to be an alias
of the old cell and the old cell is used instead.
Comparing is aided by the server list in struct afs_server_list being
sorted in UUID order and the addresses in the fileserver address lists
being sorted in address order.
The cell then retains the afs_volume object for the root.cell volume, even
if it's not mounted for future alias checking.
This necessary because:
(1) Whilst fileservers have UUIDs that are meant to be globally unique, in
practice they are not because cells get cloned without changing the
UUIDs - so afs_server records need to be per cell.
(2) Sometimes the DNS is used to make cell aliases - but if we don't know
they're the same, we may end up with multiple superblocks and multiple
afs_server records for the same thing, impairing our ability to
deliver callback notifications of third party changes
(3) The fileserver RPC API doesn't contain the cell name, so it can't tell
us which cell it's notifying and can't see that a change made to to
one cell should notify the same client that's also accessed as the
other cell.
Reported-by: Jeffrey Altman <jaltman@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Implement client support for the YFSVL.GetCellName RPC operation by which
YFS permits the canonical cell name to be queried from a VL server.
Signed-off-by: David Howells <dhowells@redhat.com>
Save more bits from the volume location database record obtained for a
server so that we can use this information in cell alias detection.
Signed-off-by: David Howells <dhowells@redhat.com>
The AFS filesystem driver is handling the CB.ProbeUuid request incorrectly.
The UUID presented in the request is that of the cache manager, not the
fileserver, so afs_deliver_cb_probe_uuid() shouldn't be using that UUID to
look up the server.
Fix this by looking up the server by address instead.
Signed-off-by: David Howells <dhowells@redhat.com>
Don't get the epoch from a server, particularly one that we're looking up
by UUID, as UUIDs may be ambiguous and may map to more than one server - so
we can't draw any conclusions from it.
Reported-by: Jeffrey Altman <jaltman@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Turn the afs_operation struct into the main way that most fileserver
operations are managed. Various things are added to the struct, including
the following:
(1) All the parameters and results of the relevant operations are moved
into it, removing corresponding fields from the afs_call struct.
afs_call gets a pointer to the op.
(2) The target volume is made the main focus of the operation, rather than
the target vnode(s), and a bunch of op->vnode->volume are made
op->volume instead.
(3) Two vnode records are defined (op->file[]) for the vnode(s) involved
in most operations. The vnode record (struct afs_vnode_param)
contains:
- The vnode pointer.
- The fid of the vnode to be included in the parameters or that was
returned in the reply (eg. FS.MakeDir).
- The status and callback information that may be returned in the
reply about the vnode.
- Callback break and data version tracking for detecting
simultaneous third-parth changes.
(4) Pointers to dentries to be updated with new inodes.
(5) An operations table pointer. The table includes pointers to functions
for issuing AFS and YFS-variant RPCs, handling the success and abort
of an operation and handling post-I/O-lock local editing of a
directory.
To make this work, the following function restructuring is made:
(A) The rotation loop that issues calls to fileservers that can be found
in each function that wants to issue an RPC (such as afs_mkdir()) is
extracted out into common code, in a new file called fs_operation.c.
(B) The rotation loops, such as the one in afs_mkdir(), are replaced with
a much smaller piece of code that allocates an operation, sets the
parameters and then calls out to the common code to do the actual
work.
(C) The code for handling the success and failure of an operation are
moved into operation functions (as (5) above) and these are called
from the core code at appropriate times.
(D) The pseudo inode getting stuff used by the dynamic root code is moved
over into dynroot.c.
(E) struct afs_iget_data is absorbed into the operation struct and
afs_iget() expects to be given an op pointer and a vnode record.
(F) Point (E) doesn't work for the root dir of a volume, but we know the
FID in advance (it's always vnode 1, unique 1), so a separate inode
getter, afs_root_iget(), is provided to special-case that.
(G) The inode status init/update functions now also take an op and a vnode
record.
(H) The RPC marshalling functions now, for the most part, just take an
afs_operation struct as their only argument. All the data they need
is held there. The result delivery functions write their answers
there as well.
(I) The call is attached to the operation and then the operation core does
the waiting.
And then the new operation code is, for the moment, made to just initialise
the operation, get the appropriate vnode I/O locks and do the same rotation
loop as before.
This lays the foundation for the following changes in the future:
(*) Overhauling the rotation (again).
(*) Support for asynchronous I/O, where the fileserver rotation must be
done asynchronously also.
Signed-off-by: David Howells <dhowells@redhat.com>
Pull networking updates from David Miller:
1) Allow setting bluetooth L2CAP modes via socket option, from Luiz
Augusto von Dentz.
2) Add GSO partial support to igc, from Sasha Neftin.
3) Several cleanups and improvements to r8169 from Heiner Kallweit.
4) Add IF_OPER_TESTING link state and use it when ethtool triggers a
device self-test. From Andrew Lunn.
5) Start moving away from custom driver versions, use the globally
defined kernel version instead, from Leon Romanovsky.
6) Support GRO vis gro_cells in DSA layer, from Alexander Lobakin.
7) Allow hard IRQ deferral during NAPI, from Eric Dumazet.
8) Add sriov and vf support to hinic, from Luo bin.
9) Support Media Redundancy Protocol (MRP) in the bridging code, from
Horatiu Vultur.
10) Support netmap in the nft_nat code, from Pablo Neira Ayuso.
11) Allow UDPv6 encapsulation of ESP in the ipsec code, from Sabrina
Dubroca. Also add ipv6 support for espintcp.
12) Lots of ReST conversions of the networking documentation, from Mauro
Carvalho Chehab.
13) Support configuration of ethtool rxnfc flows in bcmgenet driver,
from Doug Berger.
14) Allow to dump cgroup id and filter by it in inet_diag code, from
Dmitry Yakunin.
15) Add infrastructure to export netlink attribute policies to
userspace, from Johannes Berg.
16) Several optimizations to sch_fq scheduler, from Eric Dumazet.
17) Fallback to the default qdisc if qdisc init fails because otherwise
a packet scheduler init failure will make a device inoperative. From
Jesper Dangaard Brouer.
18) Several RISCV bpf jit optimizations, from Luke Nelson.
19) Correct the return type of the ->ndo_start_xmit() method in several
drivers, it's netdev_tx_t but many drivers were using
'int'. From Yunjian Wang.
20) Add an ethtool interface for PHY master/slave config, from Oleksij
Rempel.
21) Add BPF iterators, from Yonghang Song.
22) Add cable test infrastructure, including ethool interfaces, from
Andrew Lunn. Marvell PHY driver is the first to support this
facility.
23) Remove zero-length arrays all over, from Gustavo A. R. Silva.
24) Calculate and maintain an explicit frame size in XDP, from Jesper
Dangaard Brouer.
25) Add CAP_BPF, from Alexei Starovoitov.
26) Support terse dumps in the packet scheduler, from Vlad Buslov.
27) Support XDP_TX bulking in dpaa2 driver, from Ioana Ciornei.
28) Add devm_register_netdev(), from Bartosz Golaszewski.
29) Minimize qdisc resets, from Cong Wang.
30) Get rid of kernel_getsockopt and kernel_setsockopt in order to
eliminate set_fs/get_fs calls. From Christoph Hellwig.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2517 commits)
selftests: net: ip_defrag: ignore EPERM
net_failover: fixed rollback in net_failover_open()
Revert "tipc: Fix potential tipc_aead refcnt leak in tipc_crypto_rcv"
Revert "tipc: Fix potential tipc_node refcnt leak in tipc_rcv"
vmxnet3: allow rx flow hash ops only when rss is enabled
hinic: add set_channels ethtool_ops support
selftests/bpf: Add a default $(CXX) value
tools/bpf: Don't use $(COMPILE.c)
bpf, selftests: Use bpf_probe_read_kernel
s390/bpf: Use bcr 0,%0 as tail call nop filler
s390/bpf: Maintain 8-byte stack alignment
selftests/bpf: Fix verifier test
selftests/bpf: Fix sample_cnt shared between two threads
bpf, selftests: Adapt cls_redirect to call csum_level helper
bpf: Add csum_level helper for fixing up csum levels
bpf: Fix up bpf_skb_adjust_room helper's skb csum setting
sfc: add missing annotation for efx_ef10_try_update_nic_stats_vf()
crypto/chtls: IPv6 support for inline TLS
Crypto/chcr: Fixes a coccinile check error
Crypto/chcr: Fixes compilations warnings
...
set from Mauro toward the completion of the RST conversion. I *really*
hope we are getting close to the end of this. Meanwhile, those patches
reach pretty far afield to update document references around the tree;
there should be no actual code changes there. There will be, alas, more of
the usual trivial merge conflicts.
Beyond that we have more translations, improvements to the sphinx
scripting, a number of additions to the sysctl documentation, and lots of
fixes.
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Merge tag 'docs-5.8' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
"A fair amount of stuff this time around, dominated by yet another
massive set from Mauro toward the completion of the RST conversion. I
*really* hope we are getting close to the end of this. Meanwhile,
those patches reach pretty far afield to update document references
around the tree; there should be no actual code changes there. There
will be, alas, more of the usual trivial merge conflicts.
Beyond that we have more translations, improvements to the sphinx
scripting, a number of additions to the sysctl documentation, and lots
of fixes"
* tag 'docs-5.8' of git://git.lwn.net/linux: (130 commits)
Documentation: fixes to the maintainer-entry-profile template
zswap: docs/vm: Fix typo accept_threshold_percent in zswap.rst
tracing: Fix events.rst section numbering
docs: acpi: fix old http link and improve document format
docs: filesystems: add info about efivars content
Documentation: LSM: Correct the basic LSM description
mailmap: change email for Ricardo Ribalda
docs: sysctl/kernel: document unaligned controls
Documentation: admin-guide: update bug-hunting.rst
docs: sysctl/kernel: document ngroups_max
nvdimm: fixes to maintainter-entry-profile
Documentation/features: Correct RISC-V kprobes support entry
Documentation/features: Refresh the arch support status files
Revert "docs: sysctl/kernel: document ngroups_max"
docs: move locking-specific documents to locking/
docs: move digsig docs to the security book
docs: move the kref doc into the core-api book
docs: add IRQ documentation at the core-api book
docs: debugging-via-ohci1394.txt: add it to the core-api book
docs: fix references for ipmi.rst file
...
As a prelude to implementing asynchronous fileserver operations in the afs
filesystem, rename struct afs_fs_cursor to afs_operation.
This struct is going to form the core of the operation management and is
going to acquire more members in later.
Signed-off-by: David Howells <dhowells@redhat.com>
Set a flag in the call struct to indicate an unmarshalling error rather
than return and handle an error from the decoding of file statuses. This
flag is checked on a successful return from the delivery function.
Signed-off-by: David Howells <dhowells@redhat.com>
afs_vol_interest objects represent the volume IDs currently being accessed
from a fileserver. These hold lists of afs_cb_interest objects that
repesent the superblocks using that volume ID on that server.
When a callback notification from the server telling of a modification by
another client arrives, the volume ID specified in the notification is
looked up in the server's afs_vol_interest list. Through the
afs_cb_interest list, the relevant superblocks can be iterated over and the
specific inode looked up and marked in each one.
Make the following efficiency improvements:
(1) Hold rcu_read_lock() over the entire processing rather than locking it
each time.
(2) Do all the callbacks for each vid together rather than individually.
Each volume then only needs to be looked up once.
(3) afs_vol_interest objects are now stored in an rb_tree rather than a
flat list to reduce the lookup step count.
(4) afs_vol_interest lookup is now done with RCU, but because it's in an
rb_tree which may rotate under us, a seqlock is used so that if it
changes during the walk, we repeat the walk with a lock held.
With this and the preceding patch which adds RCU-based lookups in the inode
cache, target volumes/vnodes can be taken without the need to take any
locks, except on the target itself.
Signed-off-by: David Howells <dhowells@redhat.com>
Show more information in /proc/net/afs/servers to make it easier to see
what's going on with the server probing.
Signed-off-by: David Howells <dhowells@redhat.com>
When an AFS client accesses a file, it receives a limited-duration callback
promise that the server will notify it if another client changes a file.
This callback duration can be a few hours in length.
If a client mounts a volume and then an application prevents it from being
unmounted, say by chdir'ing into it, but then does nothing for some time,
the rxrpc_peer record will expire and rxrpc-level keepalive will cease.
If there is NAT or a firewall between the client and the server, the route
back for the server may close after a comparatively short duration, meaning
that attempts by the server to notify the client may then bounce.
The client, however, may (so far as it knows) still have a valid unexpired
promise and will then rely on its cached data and will not see changes made
on the server by a third party until it incidentally rechecks the status or
the promise needs renewal.
To deal with this, the client needs to regularly probe the server. This
has two effects: firstly, it keeps a route open back for the server, and
secondly, it causes the server to disgorge any notifications that got
queued up because they couldn't be sent.
Fix this by adding a mechanism to emit regular probes.
Two levels of probing are made available: Under normal circumstances the
'slow' queue will be used for a fileserver - this just probes the preferred
address once every 5 mins or so; however, if server fails to respond to any
probes, the server will shift to the 'fast' queue from which all its
interfaces will be probed every 30s. When it finally responds, the record
will switch back to the slow queue.
Further notes:
(1) Probing is now no longer driven from the fileserver rotation
algorithm.
(2) Probes are dispatched to all interfaces on a fileserver when that an
afs_server object is set up to record it.
(3) The afs_server object is removed from the probe queues when we start
to probe it. afs_is_probing_server() returns true if it's not listed
- ie. it's undergoing probing.
(4) The afs_server object is added back on to the probe queue when the
final outstanding probe completes, but the probed_at time is set when
we're about to launch a probe so that it's not dependent on the probe
duration.
(5) The timer and the work item added for this must be handed a count on
net->servers_outstanding, which they hand on or release. This makes
sure that network namespace cleanup waits for them.
Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Reported-by: Dave Botsch <botsch@cnf.cornell.edu>
Signed-off-by: David Howells <dhowells@redhat.com>
Split the usage count on the afs_server struct to have an active count that
registers who's actually using it separately from the reference count on
the object.
This allows a future patch to dispatch polling probes without advancing the
"unuse" time into the future each time we emit a probe, which would
otherwise prevent unused server records from expiring.
Included in this:
(1) The latter part of afs_destroy_server() in which the RCU destruction
of afs_server objects is invoked and the outstanding server count is
decremented is split out into __afs_put_server().
(2) afs_put_server() now calls __afs_put_server() rather then setting the
management timer.
(3) The calls begun by afs_fs_give_up_all_callbacks() and
afs_fs_get_capabilities() can now take a ref on the server record, so
afs_destroy_server() can just drop its ref and needn't wait for the
completion of these calls. They'll put the ref when they're done.
(4) Because of (3), afs_fs_probe_done() no longer needs to wake up
afs_destroy_server() with server->probe_outstanding.
(5) afs_gc_servers can be simplified. It only needs to check if
server->active is 0 rather than playing games with the refcount.
(6) afs_manage_servers() can propose a server for gc if usage == 0 rather
than if ref == 1. The gc is effected by (5).
Signed-off-by: David Howells <dhowells@redhat.com>
The U-version VLDB volume record retrieved by the VL.GetEntryByNameU rpc op
carries a change counter (the serverUnique field) for each fileserver
listed in the record as backing that volume. This is incremented whenever
the registration details for a fileserver change (such as its address
list). Note that the same value will be seen in all UVLDB records that
refer to that fileserver.
This should be checked before calling the VL server to re-query the address
list for a fileserver. If it's the same, there's no point doing the query.
Reported-by: Jeffrey Altman <jaltman@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
When a lookup is done in an AFS directory, the filesystem will speculate
and fetch up to 49 other statuses for files in the same directory and fetch
those as well, turning them into inodes or updating inodes that already
exist.
However, occasionally, a callback break might go missing due to NAT timing
out, but the afs filesystem doesn't then realise that the directory is not
up to date.
Alleviate this by using one of the status slots to check the directory in
which the lookup is being done.
Reported-by: Dave Botsch <botsch@cnf.cornell.edu>
Suggested-by: Jeffrey Altman <jaltman@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Make the inode hash table RCU searchable so that searches that want to
access or modify an inode without taking a ref on that inode can do so
without taking the inode hash table lock.
The main thing this requires is some RCU annotation on the list
manipulation operations. Inodes are already freed by RCU in most cases.
Users of this interface must take care as the inode may be still under
construction or may be being torn down around them.
There are at least three instances where this can be of use:
(1) Testing whether the inode number iunique() is going to return is
currently unique (the iunique_lock is still held).
(2) Ext4 date stamp updating.
(3) AFS callback breaking.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
cc: linux-ext4@vger.kernel.org
cc: linux-afs@lists.infradead.org
Add a helper to directly set the RXRPC_MIN_SECURITY_LEVEL sockopt from
kernel space without going through a fake uaccess.
Thanks to David Howells for the documentation updates.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
1) Fix RCU warnings in ipv6 multicast router code, from Madhuparna
Bhowmik.
2) Nexthop attributes aren't being checked properly because of
mis-initialized iterator, from David Ahern.
3) Revert iop_idents_reserve() change as it caused performance
regressions and was just working around what is really a UBSAN bug
in the compiler. From Yuqi Jin.
4) Read MAC address properly from ROM in bmac driver (double iteration
proceeds past end of address array), from Jeremy Kerr.
5) Add Microsoft Surface device IDs to r8152, from Marc Payne.
6) Prevent reference to freed SKB in __netif_receive_skb_core(), from
Boris Sukholitko.
7) Fix ACK discard behavior in rxrpc, from David Howells.
8) Preserve flow hash across packet scrubbing in wireguard, from Jason
A. Donenfeld.
9) Cap option length properly for SO_BINDTODEVICE in AX25, from Eric
Dumazet.
10) Fix encryption error checking in kTLS code, from Vadim Fedorenko.
11) Missing BPF prog ref release in flow dissector, from Jakub Sitnicki.
12) dst_cache must be used with BH disabled in tipc, from Eric Dumazet.
13) Fix use after free in mlxsw driver, from Jiri Pirko.
14) Order kTLS key destruction properly in mlx5 driver, from Tariq
Toukan.
15) Check devm_platform_ioremap_resource() return value properly in
several drivers, from Tiezhu Yang.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (71 commits)
net: smsc911x: Fix runtime PM imbalance on error
net/mlx4_core: fix a memory leak bug.
net: ethernet: ti: cpsw: fix ASSERT_RTNL() warning during suspend
net: phy: mscc: fix initialization of the MACsec protocol mode
net: stmmac: don't attach interface until resume finishes
net: Fix return value about devm_platform_ioremap_resource()
net/mlx5: Fix error flow in case of function_setup failure
net/mlx5e: CT: Correctly get flow rule
net/mlx5e: Update netdev txq on completions during closure
net/mlx5: Annotate mutex destroy for root ns
net/mlx5: Don't maintain a case of del_sw_func being null
net/mlx5: Fix cleaning unmanaged flow tables
net/mlx5: Fix memory leak in mlx5_events_init
net/mlx5e: Fix inner tirs handling
net/mlx5e: kTLS, Destroy key object after destroying the TIS
net/mlx5e: Fix allowed tc redirect merged eswitch offload cases
net/mlx5: Avoid processing commands before cmdif is ready
net/mlx5: Fix a race when moving command interface to events mode
net/mlx5: Add command entry handling completion
rxrpc: Fix a memory leak in rxkad_verify_response()
...
Fix a warning due to an uninitialised variable.
le included from ../fs/afs/fs_probe.c:11:
../fs/afs/fs_probe.c: In function 'afs_fileserver_probe_result':
../fs/afs/internal.h:1453:2: warning: 'rtt_us' may be used uninitialized in this function [-Wmaybe-uninitialized]
1453 | printk("[%-6.6s] "FMT"\n", current->comm ,##__VA_ARGS__)
| ^~~~~~
../fs/afs/fs_probe.c:35:15: note: 'rtt_us' was declared here
Signed-off-by: David Howells <dhowells@redhat.com>
Don't call req->page_done() on each page as we finish filling it with
the data coming from the network. Whilst this might speed up the
application a bit, it's a problem if there's a network failure and the
operation has to be reissued.
If this happens, an oops occurs because afs_readpages_page_done() clears
the pointer to each page it unlocks and when a retry happens, the
pointers to the pages it wants to fill are now NULL (and the pages have
been unlocked anyway).
Instead, wait till the operation completes successfully and only then
release all the pages after clearing any terminal gap (the server can
give us less data than we requested as we're allowed to ask for more
than is available).
KASAN produces a bug like the following, and even without KASAN, it can
oops and panic.
BUG: KASAN: wild-memory-access in _copy_to_iter+0x323/0x5f4
Write of size 1404 at addr 0005088000000000 by task md5sum/5235
CPU: 0 PID: 5235 Comm: md5sum Not tainted 5.7.0-rc3-fscache+ #250
Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014
Call Trace:
memcpy+0x39/0x58
_copy_to_iter+0x323/0x5f4
__skb_datagram_iter+0x89/0x2a6
skb_copy_datagram_iter+0x129/0x135
rxrpc_recvmsg_data.isra.0+0x615/0xd42
rxrpc_kernel_recv_data+0x1e9/0x3ae
afs_extract_data+0x139/0x33a
yfs_deliver_fs_fetch_data64+0x47a/0x91b
afs_deliver_to_call+0x304/0x709
afs_wait_for_call_to_complete+0x1cc/0x4ad
yfs_fs_fetch_data+0x279/0x288
afs_fetch_data+0x1e1/0x38d
afs_readpages+0x593/0x72e
read_pages+0xf5/0x21e
__do_page_cache_readahead+0x128/0x23f
ondemand_readahead+0x36e/0x37f
generic_file_buffered_read+0x234/0x680
new_sync_read+0x109/0x17e
vfs_read+0xe6/0x138
ksys_read+0xd8/0x14d
do_syscall_64+0x6e/0x8a
entry_SYSCALL_64_after_hwframe+0x49/0xb3
Fixes: 196ee9cd2d ("afs: Make afs_fs_fetch_data() take a list of pages")
Fixes: 30062bd13e ("afs: Implement YFS support in the fs client")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
rxrpc currently uses a fixed 4s retransmission timeout until the RTT is
sufficiently sampled. This can cause problems with some fileservers with
calls to the cache manager in the afs filesystem being dropped from the
fileserver because a packet goes missing and the retransmission timeout is
greater than the call expiry timeout.
Fix this by:
(1) Copying the RTT/RTO calculation code from Linux's TCP implementation
and altering it to fit rxrpc.
(2) Altering the various users of the RTT to make use of the new SRTT
value.
(3) Replacing the use of rxrpc_resend_timeout to use the calculated RTO
value instead (which is needed in jiffies), along with a backoff.
Notes:
(1) rxrpc provides RTT samples by matching the serial numbers on outgoing
DATA packets that have the RXRPC_REQUEST_ACK set and PING ACK packets
against the reference serial number in incoming REQUESTED ACK and
PING-RESPONSE ACK packets.
(2) Each packet that is transmitted on an rxrpc connection gets a new
per-connection serial number, even for retransmissions, so an ACK can
be cross-referenced to a specific trigger packet. This allows RTT
information to be drawn from retransmitted DATA packets also.
(3) rxrpc maintains the RTT/RTO state on the rxrpc_peer record rather than
on an rxrpc_call because many RPC calls won't live long enough to
generate more than one sample.
(4) The calculated SRTT value is in units of 8ths of a microsecond rather
than nanoseconds.
The (S)RTT and RTO values are displayed in /proc/net/rxrpc/peers.
Fixes: 17926a7932 ([AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both"")
Signed-off-by: David Howells <dhowells@redhat.com>
When an operation is meant to be done uninterruptibly (such as
FS.StoreData), we should not be allowing volume and server record checking
to be interrupted.
Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: David Howells <dhowells@redhat.com>
AFS keeps track of the epoch value from the rxrpc protocol to note (a) when
a fileserver appears to have restarted and (b) when different endpoints of
a fileserver do not appear to be associated with the same fileserver
(ie. all probes back from a fileserver from all of its interfaces should
carry the same epoch).
However, the AFS_SERVER_FL_HAVE_EPOCH flag that indicates that we've
received the server's epoch is never set, though it is used.
Fix this to set the flag when we first receive an epoch value from a probe
sent to the filesystem client from the fileserver.
Fixes: 3bf0fb6f33 ("afs: Probe multiple fileservers simultaneously")
Signed-off-by: David Howells <dhowells@redhat.com>
Remove three bits:
(1) afs_server::no_epoch is neither set nor used.
(2) afs_server::have_result is set and a wakeup is applied to it, but
nothing looks at it or waits on it.
(3) afs_vl_dump_edestaddrreq() prints afs_addr_list::probed, but nothing
sets it for VL servers.
Signed-off-by: David Howells <dhowells@redhat.com>
If a dentry's version is somewhere between invalid_before and the current
directory version, we should be setting it forward to the current version,
not backwards to the invalid_before version. Note that we're only doing
this at all because dentry::d_fsdata isn't large enough on a 32-bit system.
Fix this by using a separate variable for invalid_before so that we don't
accidentally clobber the current dir version.
Fixes: a4ff7401fb ("afs: Keep track of invalid-before version for dentry coherency")
Signed-off-by: David Howells <dhowells@redhat.com>
AFS directories are retained locally as a structured file, with lookup
being effected by a local search of the file contents. When a modification
(such as mkdir) happens, the dir file content is modified locally rather
than redownloading the directory.
The directory contents are accessed in a number of ways, with a number of
different locks schemes:
(1) Download of contents - dvnode->validate_lock/write in afs_read_dir().
(2) Lookup and readdir - dvnode->validate_lock/read in afs_dir_iterate(),
downgrading from (1) if necessary.
(3) d_revalidate of child dentry - dvnode->validate_lock/read in
afs_do_lookup_one() downgrading from (1) if necessary.
(4) Edit of dir after modification - page locks on individual dir pages.
Unfortunately, because (4) uses different locking scheme to (1) - (3),
nothing protects against the page being scanned whilst the edit is
underway. Even download is not safe as it doesn't lock the pages - relying
instead on the validate_lock to serialise as a whole (the theory being that
directory contents are treated as a block and always downloaded as a
block).
Fix this by write-locking dvnode->validate_lock around the edits. Care
must be taken in the rename case as there may be two different dirs - but
they need not be locked at the same time. In any case, once the lock is
taken, the directory version must be rechecked, and the edit skipped if a
later version has been downloaded by revalidation (there can't have been
any local changes because the VFS holds the inode lock, but there can have
been remote changes).
Fixes: 63a4681ff3 ("afs: Locally edit directory data for mkdir/create/unlink/...")
Signed-off-by: David Howells <dhowells@redhat.com>
Fix the length of the dump of a bad YFSFetchStatus record. The function
was copied from the AFS version, but the YFS variant contains bigger fields
and extra information, so expand the dump to match.
Signed-off-by: David Howells <dhowells@redhat.com>
The afs_deliver_fs_rename() and yfs_deliver_fs_rename() functions both only
decode the second file status returned unless the parent directories are
different - unfortunately, this means that the xdr pointer isn't advanced
and the volsync record will be read incorrectly in such an instance.
Fix this by always decoding the second status into the second
status/callback block which wasn't being used if the dirs were the same.
The afs_update_dentry_version() calls that update the directory data
version numbers on the dentries can then unconditionally use the second
status record as this will always reflect the state of the destination dir
(the two records will be identical if the destination dir is the same as
the source dir)
Fixes: 260a980317 ("[AFS]: Add "directory write" support.")
Fixes: 30062bd13e ("afs: Implement YFS support in the fs client")
Signed-off-by: David Howells <dhowells@redhat.com>
If we're decoding an AFSFetchStatus record and we see that the version is 1
and the abort code is set and we're expecting inline errors, then we store
the abort code and ignore the remaining status record (which is correct),
but we don't set the flag to say we got a valid abort code.
This can affect operation of YFS.RemoveFile2 when removing a file and the
operation of {,Y}FS.InlineBulkStatus when prospectively constructing or
updating of a set of inodes during a lookup.
Fix this to indicate the reception of a valid abort code.
Fixes: a38a75581e ("afs: Fix unlink to handle YFS.RemoveFile2 better")
Signed-off-by: David Howells <dhowells@redhat.com>
If we receive a status record that has VNOVNODE set in the abort field,
xdr_decode_AFSFetchStatus() and xdr_decode_YFSFetchStatus() don't advance
the XDR pointer, thereby corrupting anything subsequent decodes from the
same block of data.
This has the potential to affect AFS.InlineBulkStatus and
YFS.InlineBulkStatus operation, but probably doesn't since the status
records are extracted as individual blocks of data and the buffer pointer
is reset between blocks.
It does affect YFS.RemoveFile2 operation, corrupting the volsync record -
though that is not currently used.
Other operations abort the entire operation rather than returning an error
inline, in which case there is no decoding to be done.
Fix this by unconditionally advancing the xdr pointer.
Fixes: 684b0f68cf ("afs: Fix AFSFetchStatus decoder to provide OpenAFS compatibility")
Signed-off-by: David Howells <dhowells@redhat.com>
When it's probing all of a fileserver's interfaces to find which one is
best to use, afs_do_probe_fileserver() takes a lock on the server record
and notes the pointer to the address list.
It doesn't, however, pin the address list, so as soon as it drops the
lock, there's nothing to stop the address list from being freed under
us.
Fix this by taking a ref on the address list inside the locked section
and dropping it at the end of the function.
Fixes: 3bf0fb6f33 ("afs: Probe multiple fileservers simultaneously")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull networking fixes from David Miller:
1) Fix deadlock in bpf_send_signal() from Yonghong Song.
2) Fix off by one in kTLS offload of mlx5, from Tariq Toukan.
3) Add missing locking in iwlwifi mvm code, from Avraham Stern.
4) Fix MSG_WAITALL handling in rxrpc, from David Howells.
5) Need to hold RTNL mutex in tcindex_partial_destroy_work(), from Cong
Wang.
6) Fix producer race condition in AF_PACKET, from Willem de Bruijn.
7) cls_route removes the wrong filter during change operations, from
Cong Wang.
8) Reject unrecognized request flags in ethtool netlink code, from
Michal Kubecek.
9) Need to keep MAC in reset until PHY is up in bcmgenet driver, from
Doug Berger.
10) Don't leak ct zone template in act_ct during replace, from Paul
Blakey.
11) Fix flushing of offloaded netfilter flowtable flows, also from Paul
Blakey.
12) Fix throughput drop during tx backpressure in cxgb4, from Rahul
Lakkireddy.
13) Don't let a non-NULL skb->dev leave the TCP stack, from Eric
Dumazet.
14) TCP_QUEUE_SEQ socket option has to update tp->copied_seq as well,
also from Eric Dumazet.
15) Restrict macsec to ethernet devices, from Willem de Bruijn.
16) Fix reference leak in some ethtool *_SET handlers, from Michal
Kubecek.
17) Fix accidental disabling of MSI for some r8169 chips, from Heiner
Kallweit.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (138 commits)
net: Fix CONFIG_NET_CLS_ACT=n and CONFIG_NFT_FWD_NETDEV={y, m} build
net: ena: Add PCI shutdown handler to allow safe kexec
selftests/net/forwarding: define libs as TEST_PROGS_EXTENDED
selftests/net: add missing tests to Makefile
r8169: re-enable MSI on RTL8168c
net: phy: mdio-bcm-unimac: Fix clock handling
cxgb4/ptp: pass the sign of offset delta in FW CMD
net: dsa: tag_8021q: replace dsa_8021q_remove_header with __skb_vlan_pop
net: cbs: Fix software cbs to consider packet sending time
net/mlx5e: Do not recover from a non-fatal syndrome
net/mlx5e: Fix ICOSQ recovery flow with Striding RQ
net/mlx5e: Fix missing reset of SW metadata in Striding RQ reset
net/mlx5e: Enhance ICOSQ WQE info fields
net/mlx5_core: Set IB capability mask1 to fix ib_srpt connection failure
selftests: netfilter: add nfqueue test case
netfilter: nft_fwd_netdev: allow to redirect to ifb via ingress
netfilter: nft_fwd_netdev: validate family and chain type
netfilter: nft_set_rbtree: Detect partial overlaps on insertion
netfilter: nft_set_rbtree: Introduce and use nft_rbtree_interval_start()
netfilter: nft_set_pipapo: Separate partial and complete overlap cases on insertion
...
Fix the handling of signals in client rxrpc calls made by the afs
filesystem. Ignore signals completely, leaving call abandonment or
connection loss to be detected by timeouts inside AF_RXRPC.
Allowing a filesystem call to be interrupted after the entire request has
been transmitted and an abort sent means that the server may or may not
have done the action - and we don't know. It may even be worse than that
for older servers.
Fixes: bc5e3a546d ("rxrpc: Use MSG_WAITALL to tell sendmsg() to temporarily ignore signals")
Signed-off-by: David Howells <dhowells@redhat.com>
When an AFS service handler function aborts a call, AF_RXRPC marks the call
as complete - which means that it's not going to get any more packets from
the receiver. This is a problem because reception of the final ACK is what
triggers afs_deliver_to_call() to drop the final ref on the afs_call
object.
Instead, aborted AFS service calls may then just sit around waiting for
ever or until they're displaced by a new call on the same connection
channel or a connection-level abort.
Fix this by calling afs_set_call_complete() to finalise the afs_call struct
representing the call.
However, we then need to drop the ref that stops the call from being
deallocated. We can do this in afs_set_call_complete(), as the work queue
is holding a separate ref of its own, but then we shouldn't do it in
afs_process_async_call() and afs_delete_async_call().
call->drop_ref is set to indicate that a ref needs dropping for a call and
this is dealt with when we transition a call to AFS_CALL_COMPLETE.
But then we also need to get rid of the ref that pins an asynchronous
client call. We can do this by the same mechanism, setting call->drop_ref
for an async client call too.
We can also get rid of call->incoming since nothing ever sets it and only
one thing ever checks it (futilely).
A trace of the rxrpc_call and afs_call struct ref counting looks like:
<idle>-0 [001] ..s5 164.764892: rxrpc_call: c=00000002 SEE u=3 sp=rxrpc_new_incoming_call+0x473/0xb34 a=00000000442095b5
<idle>-0 [001] .Ns5 164.766001: rxrpc_call: c=00000002 QUE u=4 sp=rxrpc_propose_ACK+0xbe/0x551 a=00000000442095b5
<idle>-0 [001] .Ns4 164.766005: rxrpc_call: c=00000002 PUT u=3 sp=rxrpc_new_incoming_call+0xa3f/0xb34 a=00000000442095b5
<idle>-0 [001] .Ns7 164.766433: afs_call: c=00000002 WAKE u=2 o=11 sp=rxrpc_notify_socket+0x196/0x33c
kworker/1:2-1810 [001] ...1 164.768409: rxrpc_call: c=00000002 SEE u=3 sp=rxrpc_process_call+0x25/0x7ae a=00000000442095b5
kworker/1:2-1810 [001] ...1 164.769439: rxrpc_tx_packet: c=00000002 e9f1a7a8:95786a88:00000008:09c5 00000001 00000000 02 22 ACK CallAck
kworker/1:2-1810 [001] ...1 164.769459: rxrpc_call: c=00000002 PUT u=2 sp=rxrpc_process_call+0x74f/0x7ae a=00000000442095b5
kworker/1:2-1810 [001] ...1 164.770794: afs_call: c=00000002 QUEUE u=3 o=12 sp=afs_deliver_to_call+0x449/0x72c
kworker/1:2-1810 [001] ...1 164.770829: afs_call: c=00000002 PUT u=2 o=12 sp=afs_process_async_call+0xdb/0x11e
kworker/1:2-1810 [001] ...2 164.771084: rxrpc_abort: c=00000002 95786a88:00000008 s=0 a=1 e=1 K-1
kworker/1:2-1810 [001] ...1 164.771461: rxrpc_tx_packet: c=00000002 e9f1a7a8:95786a88:00000008:09c5 00000002 00000000 04 00 ABORT CallAbort
kworker/1:2-1810 [001] ...1 164.771466: afs_call: c=00000002 PUT u=1 o=12 sp=SRXAFSCB_ProbeUuid+0xc1/0x106
The abort generated in SRXAFSCB_ProbeUuid(), labelled "K-1", indicates that
the local filesystem/cache manager didn't recognise the UUID as its own.
Fixes: 2067b2b3f4 ("afs: Fix the CB.ProbeUuid service handler to reply correctly")
Signed-off-by: David Howells <dhowells@redhat.com>
Fix a couple of tracelines to indicate the usage count after the atomic op,
not the usage count before it to be consistent with other afs and rxrpc
trace lines.
Change the wording of the afs_call_trace_work trace ID label from "WORK" to
"QUEUE" to reflect the fact that it's queueing work, not doing work.
Fixes: 341f741f04 ("afs: Refcount the afs_call struct")
Signed-off-by: David Howells <dhowells@redhat.com>
Fix the interruptibility of kernel-initiated client calls so that they're
either only interruptible when they're waiting for a call slot to come
available or they're not interruptible at all. Either way, they're not
interruptible during transmission.
This should help prevent StoreData calls from being interrupted when
writeback is in progress. It doesn't, however, handle interruption during
the receive phase.
Userspace-initiated calls are still interruptable. After the signal has
been handled, sendmsg() will return the amount of data copied out of the
buffer and userspace can perform another sendmsg() call to continue
transmission.
Fixes: bc5e3a546d ("rxrpc: Use MSG_WAITALL to tell sendmsg() to temporarily ignore signals")
Signed-off-by: David Howells <dhowells@redhat.com>
afs_put_addrlist() casts kfree() to rcu_callback_t. Apart from being wrong
in theory, this might also blow up when people start enforcing function
types via compiler instrumentation, and it means the rcu_head has to be
first in struct afs_addr_list.
Use kfree_rcu() instead, it's simpler and more correct.
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull vfs file system parameter updates from Al Viro:
"Saner fs_parser.c guts and data structures. The system-wide registry
of syntax types (string/enum/int32/oct32/.../etc.) is gone and so is
the horror switch() in fs_parse() that would have to grow another case
every time something got added to that system-wide registry.
New syntax types can be added by filesystems easily now, and their
namespace is that of functions - not of system-wide enum members. IOW,
they can be shared or kept private and if some turn out to be widely
useful, we can make them common library helpers, etc., without having
to do anything whatsoever to fs_parse() itself.
And we already get that kind of requests - the thing that finally
pushed me into doing that was "oh, and let's add one for timeouts -
things like 15s or 2h". If some filesystem really wants that, let them
do it. Without somebody having to play gatekeeper for the variants
blessed by direct support in fs_parse(), TYVM.
Quite a bit of boilerplate is gone. And IMO the data structures make a
lot more sense now. -200LoC, while we are at it"
* 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (25 commits)
tmpfs: switch to use of invalfc()
cgroup1: switch to use of errorfc() et.al.
procfs: switch to use of invalfc()
hugetlbfs: switch to use of invalfc()
cramfs: switch to use of errofc() et.al.
gfs2: switch to use of errorfc() et.al.
fuse: switch to use errorfc() et.al.
ceph: use errorfc() and friends instead of spelling the prefix out
prefix-handling analogues of errorf() and friends
turn fs_param_is_... into functions
fs_parse: handle optional arguments sanely
fs_parse: fold fs_parameter_desc/fs_parameter_spec
fs_parser: remove fs_parameter_description name field
add prefix to fs_context->log
ceph_parse_param(), ceph_parse_mon_ips(): switch to passing fc_log
new primitive: __fs_parse()
switch rbd and libceph to p_log-based primitives
struct p_log, variants of warnf() et.al. taking that one instead
teach logfc() to handle prefices, give it saner calling conventions
get rid of cg_invalf()
...
Unused now.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Don't do a single array; attach them to fsparam_enum() entry
instead. And don't bother trying to embed the names into those -
it actually loses memory, with no real speedup worth mentioning.
Simplifies validation as well.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The afs filesystem needs to prohibit certain characters from cell names,
such as '/', as these are used to form filenames in procfs, leading to
the following warning being generated:
WARNING: CPU: 0 PID: 3489 at fs/proc/generic.c:178
Fix afs_alloc_cell() to disallow nonprintable characters, '/', '@' and
names that begin with a dot.
Remove the check for "@cell" as that is then redundant.
This can be tested by running:
echo add foo/.bar 1.2.3.4 >/proc/fs/afs/cells
Note that we will also need to deal with:
- Names ending in ".invalid" shouldn't be passed to the DNS.
- Names that contain non-valid domainname chars shouldn't be passed to
the DNS.
- DNS replies that say "your-dns-needs-immediate-attention.<gTLD>" and
replies containing A records that say 127.0.53.53 should be
considered invalid.
[https://www.icann.org/en/system/files/files/name-collision-mitigation-01aug14-en.pdf]
but these need to be dealt with by the kafs-client DNS program rather
than the kernel.
Reported-by: syzbot+b904ba7c947a37b4b291@syzkaller.appspotmail.com
Cc: stable@kernel.org
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge misc fixes from David Howells.
Two afs fixes and a key refcounting fix.
* dhowells:
afs: Fix afs_lookup() to not clobber the version on a new dentry
afs: Fix use-after-loss-of-ref
keys: Fix request_key() cache
Fix afs_lookup() to not clobber the version set on a new dentry by
afs_do_lookup() - especially as it's using the wrong version of the
version (we need to use the one given to us by whatever op the dir
contents correspond to rather than what's in the afs_vnode).
Fixes: 9dd0b82ef5 ("afs: Fix missing dentry data version updating")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
afs_lookup() has a tracepoint to indicate the outcome of
d_splice_alias(), passing it the inode to retrieve the fid from.
However, the function gave up its ref on that inode when it called
d_splice_alias(), which may have failed and dropped the inode.
Fix this by caching the fid.
Fixes: 80548b0399 ("afs: Add more tracepoints")
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Show the name of each volume in /proc/net/afs/<cell>/volumes to make it
easier to work out the name corresponding to a volume ID. This makes it
easier to work out which mounts in /proc/mounts correspond to which volume
ID.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Fix missing cell comparison in afs_test_super(). Without this, any pair
volumes that have the same volume ID will share a superblock, no matter the
cell, unless they're in different network namespaces.
Normally, most users will only deal with a single cell and so they won't
see this. Even if they do look into a second cell, they won't see a
problem unless they happen to hit a volume with the same ID as one they've
already got mounted.
Before the patch:
# ls /afs/grand.central.org/archive
linuxdev/ mailman/ moin/ mysql/ pipermail/ stage/ twiki/
# ls /afs/kth.se/
linuxdev/ mailman/ moin/ mysql/ pipermail/ stage/ twiki/
# cat /proc/mounts | grep afs
none /afs afs rw,relatime,dyn,autocell 0 0
#grand.central.org:root.cell /afs/grand.central.org afs ro,relatime 0 0
#grand.central.org:root.archive /afs/grand.central.org/archive afs ro,relatime 0 0
#grand.central.org:root.archive /afs/kth.se afs ro,relatime 0 0
After the patch:
# ls /afs/grand.central.org/archive
linuxdev/ mailman/ moin/ mysql/ pipermail/ stage/ twiki/
# ls /afs/kth.se/
admin/ common/ install/ OldFiles/ service/ system/
bakrestores/ home/ misc/ pkg/ src/ wsadmin/
# cat /proc/mounts | grep afs
none /afs afs rw,relatime,dyn,autocell 0 0
#grand.central.org:root.cell /afs/grand.central.org afs ro,relatime 0 0
#grand.central.org:root.archive /afs/grand.central.org/archive afs ro,relatime 0 0
#kth.se:root.cell /afs/kth.se afs ro,relatime 0 0
Fixes: ^1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: Carsten Jacobi <jacobi@de.ibm.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Tested-by: Jonathan Billings <jsbillings@jsbillings.org>
cc: Todd DeSantis <atd@us.ibm.com>
Fix the lookup method on the dynamic root directory such that creation
calls, such as mkdir, open(O_CREAT), symlink, etc. fail with EOPNOTSUPP
rather than failing with some odd error (such as EEXIST).
lookup() itself tries to create automount directories when it is invoked.
These are cached locally in RAM and not committed to storage.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Tested-by: Jonathan Billings <jsbillings@jsbillings.org>
Each AFS mountpoint has strings that define the target to be mounted. This
is required to end in a dot that is supposed to be stripped off. The
string can include suffixes of ".readonly" or ".backup" - which are
supposed to come before the terminal dot. To add to the confusion, the "fs
lsmount" afs utility does not show the terminal dot when displaying the
string.
The kernel mount source string parser, however, assumes that the terminal
dot marks the suffix and that the suffix is always "" and is thus ignored.
In most cases, there is no suffix and this is not a problem - but if there
is a suffix, it is lost and this affects the ability to mount the correct
volume.
The command line mount command, on the other hand, is expected not to
include a terminal dot - so the problem doesn't arise there.
Fix this by making sure that the dot exists and then stripping it when
passing the string to the mount configuration.
Fixes: bec5eb6141 ("AFS: Implement an autocell mount capability [ver #2]")
Reported-by: Jonathan Billings <jsbillings@jsbillings.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Tested-by: Jonathan Billings <jsbillings@jsbillings.org>
Make the AFS dynamic root superblock R/W so that SELinux can set the
security label on it. Without this, upgrades to, say, the Fedora
filesystem-afs RPM fail if afs is mounted on it because the SELinux label
can't be (re-)applied.
It might be better to make it possible to bypass the R/O check for LSM
label application through setxattr.
Fixes: 4d673da145 ("afs: Support the AFS dynamic root")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
cc: selinux@vger.kernel.org
cc: linux-security-module@vger.kernel.org
afs_find_server tries to find a server that has an address that
matches the transport address of an rxrpc peer. The code assumes
that the transport address is always ipv6, with ipv4 represented
as ipv4 mapped addresses, but that's not the case. If the transport
family is AF_INET, srx->transport.sin6.sin6_addr.s6_addr32[] will
be beyond the actual ipv4 address and will always be 0, and all
ipv4 addresses will be seen as matching.
As a result, the first ipv4 address seen on any server will be
considered a match, and the server returned may be the wrong one.
One of the consequences is that callbacks received over ipv4 will
only be correctly applied for the server that happens to have the
first ipv4 address on the fs_addresses4 list. Callbacks over ipv4
from all other servers are dropped, causing the client to serve stale
data.
This is fixed by looking at the transport family, and comparing ipv4
addresses based on a sockaddr_in structure rather than a sockaddr_in6.
Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
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Merge tag 'afs-next-20191121' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull AFS updates from David Howells:
"Minor cleanups and fix:
- Minor fix to make some debugging statements display information
from the correct iov_iter.
- Rename some members and variables to make things more obvious or
consistent.
- Provide a helper to wrap increments of the usage count on the
afs_read struct.
- Use scnprintf() to print into a stack buffer rather than sprintf().
- Remove some set but unused variables"
* tag 'afs-next-20191121' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
afs: Remove set but not used variable 'ret'
afs: Remove set but not used variables 'before', 'after'
afs: xattr: use scnprintf
afs: Introduce an afs_get_read() refcount helper
afs: Rename desc -> req in afs_fetch_data()
afs: Switch the naming of call->iter and call->_iter
afs: Use call->_iter not &call->iter in debugging statements
Pull RCU updates from Ingo Molnar:
"The main changes in this cycle were:
- Dynamic tick (nohz) updates, perhaps most notably changes to force
the tick on when needed due to lengthy in-kernel execution on CPUs
on which RCU is waiting.
- Linux-kernel memory consistency model updates.
- Replace rcu_swap_protected() with rcu_prepace_pointer().
- Torture-test updates.
- Documentation updates.
- Miscellaneous fixes"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
security/safesetid: Replace rcu_swap_protected() with rcu_replace_pointer()
net/sched: Replace rcu_swap_protected() with rcu_replace_pointer()
net/netfilter: Replace rcu_swap_protected() with rcu_replace_pointer()
net/core: Replace rcu_swap_protected() with rcu_replace_pointer()
bpf/cgroup: Replace rcu_swap_protected() with rcu_replace_pointer()
fs/afs: Replace rcu_swap_protected() with rcu_replace_pointer()
drivers/scsi: Replace rcu_swap_protected() with rcu_replace_pointer()
drm/i915: Replace rcu_swap_protected() with rcu_replace_pointer()
x86/kvm/pmu: Replace rcu_swap_protected() with rcu_replace_pointer()
rcu: Upgrade rcu_swap_protected() to rcu_replace_pointer()
rcu: Suppress levelspread uninitialized messages
rcu: Fix uninitialized variable in nocb_gp_wait()
rcu: Update descriptions for rcu_future_grace_period tracepoint
rcu: Update descriptions for rcu_nocb_wake tracepoint
rcu: Remove obsolete descriptions for rcu_barrier tracepoint
rcu: Ensure that ->rcu_urgent_qs is set before resched IPI
workqueue: Convert for_each_wq to use built-in list check
rcu: Several rcu_segcblist functions can be static
rcu: Remove unused function hlist_bl_del_init_rcu()
Documentation: Rename rcu_node_context_switch() to rcu_note_context_switch()
...
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Merge tag 'printk-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk
Pull printk updates from Petr Mladek:
- Allow to print symbolic error names via new %pe modifier.
- Use pr_warn() instead of the remaining pr_warning() calls. Fix
formatting of the related lines.
- Add VSPRINTF entry to MAINTAINERS.
* tag 'printk-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk: (32 commits)
checkpatch: don't warn about new vsprintf pointer extension '%pe'
MAINTAINERS: Add VSPRINTF
tools lib api: Renaming pr_warning to pr_warn
ASoC: samsung: Use pr_warn instead of pr_warning
lib: cpu_rmap: Use pr_warn instead of pr_warning
trace: Use pr_warn instead of pr_warning
dma-debug: Use pr_warn instead of pr_warning
vgacon: Use pr_warn instead of pr_warning
fs: afs: Use pr_warn instead of pr_warning
sh/intc: Use pr_warn instead of pr_warning
scsi: Use pr_warn instead of pr_warning
platform/x86: intel_oaktrail: Use pr_warn instead of pr_warning
platform/x86: asus-laptop: Use pr_warn instead of pr_warning
platform/x86: eeepc-laptop: Use pr_warn instead of pr_warning
oprofile: Use pr_warn instead of pr_warning
of: Use pr_warn instead of pr_warning
macintosh: Use pr_warn instead of pr_warning
idsn: Use pr_warn instead of pr_warning
ide: Use pr_warn instead of pr_warning
crypto: n2: Use pr_warn instead of pr_warning
...
By default s_maxbytes is set to MAX_NON_LFS, which limits the usable
file size to 2GB, enforced by the vfs.
Commit b9b1f8d593 ("AFS: write support fixes") added support for the
64-bit fetch and store server operations, but did not change this value.
As a result, attempts to write past the 2G mark result in EFBIG errors:
$ dd if=/dev/zero of=foo bs=1M count=1 seek=2048
dd: error writing 'foo': File too large
Set s_maxbytes to MAX_LFS_FILESIZE.
Fixes: b9b1f8d593 ("AFS: write support fixes")
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Servers sending callback breaks to the YFS_CM_SERVICE service may
send up to YFSCBMAX (1024) fids in a single RPC. Anything over
AFSCBMAX (50) will cause the assert in afs_break_callbacks to trigger.
Remove the assert, as the count has already been checked against
the appropriate max values in afs_deliver_cb_callback and
afs_deliver_yfs_cb_callback.
Fixes: 35dbfba311 ("afs: Implement the YFS cache manager service")
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fixes gcc '-Wunused-but-set-variable' warning:
fs/afs/server.c: In function afs_install_server:
fs/afs/server.c:157:6: warning: variable ret set but not used [-Wunused-but-set-variable]
It is not used since commit d2ddc776a4 ("afs:
Overhaul volume and server record caching and fileserver rotation")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Fixes gcc '-Wunused-but-set-variable' warning:
fs/afs/dir_edit.c: In function afs_set_contig_bits:
fs/afs/dir_edit.c:75:20: warning: variable after set but not used [-Wunused-but-set-variable]
fs/afs/dir_edit.c: In function afs_set_contig_bits:
fs/afs/dir_edit.c:75:12: warning: variable before set but not used [-Wunused-but-set-variable]
fs/afs/dir_edit.c: In function afs_clear_contig_bits:
fs/afs/dir_edit.c💯20: warning: variable after set but not used [-Wunused-but-set-variable]
fs/afs/dir_edit.c: In function afs_clear_contig_bits:
fs/afs/dir_edit.c💯12: warning: variable before set but not used [-Wunused-but-set-variable]
They are never used since commit 63a4681ff3.
Fixes: 63a4681ff3 ("afs: Locally edit directory data for mkdir/create/unlink/...")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: David Howells <dhowells@redhat.com>
sprintf and snprintf are fragile in future maintenance, switch to
using scnprintf to ensure no accidental Use After Free conditions
are introduced.
Signed-off-by: Mark Salyzyn <salyzyn@android.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
Cc: David Howells <dhowells@redhat.com>
Cc: linux-afs@lists.infradead.org
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: David Howells <dhowells@redhat.com>
Change the name of call->iter to call->def_iter to represent the default
iterator.
Change the name of call->_iter to call->iter to represent the iterator
actually being used.
Signed-off-by: David Howells <dhowells@redhat.com>
Use call->_iter not &call->iter in debugging statements as the latter is a
convenience iter whereas the former represents we're actually doing at the
moment.
Signed-off-by: David Howells <dhowells@redhat.com>
In afs_wait_for_call_to_complete(), rather than immediately aborting an
operation if a signal occurs, the code attempts to wait for it to
complete, using a schedule timeout of 2*RTT (or min 2 jiffies) and a
check that we're still receiving relevant packets from the server before
we consider aborting the call. We may even ping the server to check on
the status of the call.
However, there's a missing timeout reset in the event that we do
actually get a packet to process, such that if we then get a couple of
short stalls, we then time out when progress is actually being made.
Fix this by resetting the timeout any time we get something to process.
If it's the failure of the call then the call state will get changed and
we'll exit the loop shortly thereafter.
A symptom of this is data fetches and stores failing with EINTR when
they really shouldn't.
Fixes: bc5e3a546d ("rxrpc: Use MSG_WAITALL to tell sendmsg() to temporarily ignore signals")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When a lookup is done, the afs filesystem will perform a bulk status-fetch
operation on the requested vnode (file) plus the next 49 other vnodes from
the directory list (in AFS, directory contents are downloaded as blobs and
parsed locally). When the results are received, it will speculatively
populate the inode cache from the extra data.
However, if the lookup races with another lookup on the same directory, but
for a different file - one that's in the 49 extra fetches, then if the bulk
status-fetch operation finishes first, it will try and update the inode
from the other lookup.
If this other inode is still in the throes of being created, however, this
will cause an assertion failure in afs_apply_status():
BUG_ON(test_bit(AFS_VNODE_UNSET, &vnode->flags));
on or about fs/afs/inode.c:175 because it expects data to be there already
that it can compare to.
Fix this by skipping the update if the inode is being created as the
creator will presumably set up the inode with the same information.
Fixes: 39db9815da ("afs: Fix application of the results of a inline bulk status fetch")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit replaces the use of rcu_swap_protected() with the more
intuitively appealing rcu_replace_pointer() as a step towards removing
rcu_swap_protected().
Link: https://lore.kernel.org/lkml/CAHk-=wiAsJLw1egFEE=Z7-GGtM6wcvtyytXZA1+BHqta4gg6Hw@mail.gmail.com/
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
[ paulmck: From rcu_replace() to rcu_replace_pointer() per Ingo Molnar. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Acked-by: David Howells <dhowells@redhat.com>
Cc: <linux-afs@lists.infradead.org>
Cc: <linux-kernel@vger.kernel.org>
David Howells