We've tried to prevent running out of space with COMPOUND_SLACK_SPACE
and special checking in those operations (getattr) whose result can vary
enormously.
However:
- COMPOUND_SLACK_SPACE may be difficult to maintain as we add
more protocol.
- BUG_ON or page faulting on failure seems overly fragile.
- Especially in the 4.1 case, we prefer not to fail compounds
just because the returned result came *close* to session
limits. (Though perfect enforcement here may be difficult.)
- I'd prefer encoding to be uniform for all encoders instead of
having special exceptions for encoders containing, for
example, attributes.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Normally xdr encoding proceeds in a single pass from start of a buffer
to end, but sometimes we have to write a few bytes to an earlier
position.
Use write_bytes_to_xdr_buf for these cases rather than saving a pointer
to write to. We plan to rewrite xdr_reserve_space to handle encoding
across page boundaries using a scratch buffer, and don't want to risk
writing to a pointer that was contained in a scratch buffer.
Also it will no longer be safe to calculate lengths by subtracting two
pointers, so use xdr_buf offsets instead.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
xdr_reserve_space should now be calculating the length correctly as we
go, so there's no longer any need to fix it up here.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This is a cosmetic change for now; no change in behavior.
Note we're just depending on xdr_reserve_space to do the bounds checking
for us, we're not really depending on its adjustment of iovec or xdr_buf
lengths yet, as those are fixed up by as necessary after the fact by
read-link operations and by nfs4svc_encode_compoundres. However we do
have to update xdr->iov on read-like operations to prevent
xdr_reserve_space from messing with the already-fixed-up length of the
the head.
When the attribute encoding fails partway through we have to undo the
length adjustments made so far. We do it manually for now, but later
patches will add an xdr_truncate_encode() helper to handle cases like
this.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This post-encoding check should be taking into account the need to
encode at least an out-of-space error to the following op (if any).
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
If nfsd4_check_resp_size() returns an error then we should really be
truncating the reply here, otherwise we may leave extra garbage at the
end of the rpc reply.
Also add a warning to catch any cases where our reply-size estimates may
be wrong in the case of a non-idempotent operation.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Currently if the nfs-level part of a reply would be too large, we'll
return an error to the client. But if the nfs-level part fits and
leaves no room for krb5p or krb5i stuff, then we just drop the request
entirely.
That's no good. Instead, reserve some slack space at the end of the
buffer and make sure we fail outright if we'd come close.
The slack space here is a massive overstimate of what's required, we
should probably try for a tighter limit at some point.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Just change the nfsd4_encode_getattr api. Not changing any code or
adding any new functionality yet.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This is a mechanical transformation with no change in behavior.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Currently a non-idempotent op reply may be cached if it fails in the
proc code but not if it fails at xdr decoding. I doubt there are any
xdr-decoding-time errors that would make this a problem in practice, so
this probably isn't a serious bug.
The space estimates should also take into account space required for
encoding of error returns. Again, not a practical problem, though it
would become one after future patches which will tighten the space
estimates.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The client is actually asking for 2532 bytes. I suspect that's a
mistake. But maybe we can allow some more. In theory lock needs more
if it might return a maximum-length lockowner in the denied case.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
OP_MODIFIES_SOMETHING flags operations that we should be careful not to
initiate without being sure we have the buffer space to encode a reply.
None of these ops fall into that category.
We could probably remove a few more, but this isn't a very important
problem at least for ops whose reply size is easy to estimate.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
PF_LESS_THROTTLE has a very specific use case: to avoid deadlocks
and live-locks while writing to the page cache in a loop-back
NFS mount situation.
It therefore makes sense to *only* set PF_LESS_THROTTLE in this
situation.
We now know when a request came from the local-host so it could be a
loop-back mount. We already know when we are handling write requests,
and when we are doing anything else.
So combine those two to allow nfsd to still be throttled (like any
other process) in every situation except when it is known to be
problematic.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
No need for a kmem_cache_destroy wrapper in nfsd, just do proper
goto based unwinding.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Assignments should not happen inside an if conditional, but in the line
before. This issue was reported by checkpatch.
The semantic patch that makes this change is as follows
(http://coccinelle.lip6.fr/):
// <smpl>
@@
identifier i1;
expression e1;
statement S;
@@
-if(!(i1 = e1)) S
+i1 = e1;
+if(!i1)
+S
// </smpl>
It has been tested by compilation.
Signed-off-by: Benoit Taine <benoit.taine@lip6.fr>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We're not cleaning up everything we need to on error. In particular,
we're not removing our lease. Among other problems this can cause the
struct nfs4_file used as fl_owner to be referenced after it has been
destroyed.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We're clearing the SUID/SGID bits on write by hand in nfsd_vfs_write,
even though the subsequent vfs_writev() call will end up doing this for
us (through file system write methods eventually calling
file_remove_suid(), e.g., from __generic_file_aio_write).
So, remove the redundant nfsd code.
The only change in behavior is when the write is by root, in which case
we previously cleared SUID/SGID, but will now leave it alone. The new
behavior is the behavior of every filesystem we've checked.
It seems better to be consistent with local filesystem behavior. And
the security advantage seems limited as root could always restore these
bits by hand if it wanted.
SUID/SGID is not cleared after writing data with (root, local ext4),
File: ‘test’
Size: 0 Blocks: 0 IO Block: 4096 regular
empty file
Device: 803h/2051d Inode: 1200137 Links: 1
Access: (4777/-rwsrwxrwx) Uid: ( 0/ root) Gid: ( 0/ root)
Context: unconfined_u:object_r:admin_home_t:s0
Access: 2014-04-18 21:36:31.016029014 +0800
Modify: 2014-04-18 21:36:31.016029014 +0800
Change: 2014-04-18 21:36:31.026030285 +0800
Birth: -
File: ‘test’
Size: 5 Blocks: 8 IO Block: 4096 regular file
Device: 803h/2051d Inode: 1200137 Links: 1
Access: (4777/-rwsrwxrwx) Uid: ( 0/ root) Gid: ( 0/ root)
Context: unconfined_u:object_r:admin_home_t:s0
Access: 2014-04-18 21:36:31.016029014 +0800
Modify: 2014-04-18 21:36:31.040032065 +0800
Change: 2014-04-18 21:36:31.040032065 +0800
Birth: -
With no_root_squash, (root, remote ext4), SUID/SGID are cleared,
File: ‘test’
Size: 0 Blocks: 0 IO Block: 262144 regular
empty file
Device: 24h/36d Inode: 786439 Links: 1
Access: (4777/-rwsrwxrwx) Uid: ( 1000/ test) Gid: ( 1000/ test)
Context: system_u:object_r:nfs_t:s0
Access: 2014-04-18 21:45:32.155805097 +0800
Modify: 2014-04-18 21:45:32.155805097 +0800
Change: 2014-04-18 21:45:32.168806749 +0800
Birth: -
File: ‘test’
Size: 5 Blocks: 8 IO Block: 262144 regular file
Device: 24h/36d Inode: 786439 Links: 1
Access: (0777/-rwxrwxrwx) Uid: ( 1000/ test) Gid: ( 1000/ test)
Context: system_u:object_r:nfs_t:s0
Access: 2014-04-18 21:45:32.155805097 +0800
Modify: 2014-04-18 21:45:32.184808783 +0800
Change: 2014-04-18 21:45:32.184808783 +0800
Birth: -
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The current code assumes a one-to-one lockowner<->lock stateid
correspondance.
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The nfsv4 state code has always assumed a one-to-one correspondance
between lock stateid's and lockowners even if it appears not to in some
places.
We may actually change that, but for now when FREE_STATEID releases a
lock stateid it also needs to release the parent lockowner.
Symptoms were a subsequent LOCK crashing in find_lockowner_str when it
calls same_lockowner_ino on a lockowner that unexpectedly has an empty
so_stateids list.
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
As of 06f9cc12ca "nfsd4: don't create
unnecessary mask acl", any non-trivial ACL will be left with an
unitialized entry, and a trivial ACL may write one entry beyond what's
allocated.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Use fh_fsid when reffering to the fsid part of the filehandle. The
variable length auth field envisioned in nfsfh wasn't ever implemented.
Also clean up some lose ends around this and document the file handle
format better.
Btw, why do we even export nfsfh.h to userspace? The file handle very
much is kernel private, and nothing in nfs-utils include the header
either.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
commit 4ac7249ea5 have remove all EXPORT_SYMBOL,
linux/export.h is not needed, just clean it.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Move the state locking and file descriptor reference out from the
callers and into nfs4_preprocess_stateid_op() itself.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
They do not need to be used outside fs/nfsd/nfs4state.c
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
There is almost nothing left it in, just merge it into the only file
that includes it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
There are no legitimate users outside of fs/nfsd, so move it there.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
There are no legitimate users outside of fs/nfsd, so move it there.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The only real user of this header is fs/nfsd/nfsfh.h, so merge the
two. Various lockѕ source files used it to indirectly get other
sunrpc or nfs headers, so fix those up.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
It is large, it is used in more than one place, and it is not performance
critical. Let gcc figure out whether it should be inlined...
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
When building without CONFIG_SYSCTL, the compiler saw an unused
label. This moves the label into the #ifdef it is used under.
fs/lockd/svc.c: In function ‘init_nlm’:
fs/lockd/svc.c:626:1: warning: label ‘err_sysctl’ defined but not used [-Wunused-label]
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Mainly to ensure that we don't leave any hanging timers.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Aside from making it clearer what is non-trivial in create_client(), it
also fixes a bug whereby we can call free_client() before idr_init()
has been called.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Since we're still limiting attributes to a page, the result here is that
a large getattr result will return NFS4ERR_REP_TOO_BIG/TOO_BIG_TO_CACHE
instead of NFS4ERR_RESOURCE.
Both error returns are wrong, and the real bug here is the arbitrary
limit on getattr results, fixed by as-yet out-of-tree patches. But at a
minimum we can make life easier for clients by sticking to one broken
behavior in released kernels instead of two....
Trond says:
one immediate consequence of this patch will be that NFSv4.1
clients will now report EIO instead of EREMOTEIO if they hit the
problem. That may make debugging a little less obvious.
Another consequence will be that if we ever do try to add client
side handling of NFS4ERR_REP_TOO_BIG, then we now have to deal
with the “handle existing buggy server” syndrome.
Reported-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
...otherwise the logic in the timeout handling doesn't work correctly.
Spotted-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
A fl->fl_break_time of 0 has a special meaning to the lease break code
that basically means "never break the lease". knfsd uses this to ensure
that leases don't disappear out from under it.
Unfortunately, the code in __break_lease can end up passing this value
to wait_event_interruptible as a timeout, which prevents it from going
to sleep at all. This causes __break_lease to spin in a tight loop and
causes soft lockups.
Fix this by ensuring that we pass a minimum value of 1 as a timeout
instead.
Cc: <stable@vger.kernel.org>
Cc: J. Bruce Fields <bfields@fieldses.org>
Reported-by: Terry Barnaby <terry1@beam.ltd.uk>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
On 32 bit, size_t is "unsigned int", not "unsigned long", causing the
following warning when comparing with PAGE_SIZE, which is always "unsigned
long":
fs/cifs/file.c: In function ‘cifs_readdata_to_iov’:
fs/cifs/file.c:2757: warning: comparison of distinct pointer types lacks a cast
Introduced by commit 7f25bba819 ("cifs_iovec_read: keep iov_iter
between the calls of cifs_readdata_to_iov()"), which changed the
signedness of "remaining" and the code from min_t() to min().
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull yet more networking updates from David Miller:
1) Various fixes to the new Redpine Signals wireless driver, from
Fariya Fatima.
2) L2TP PPP connect code takes PMTU from the wrong socket, fix from
Dmitry Petukhov.
3) UFO and TSO packets differ in whether they include the protocol
header in gso_size, account for that in skb_gso_transport_seglen().
From Florian Westphal.
4) If VLAN untagging fails, we double free the SKB in the bridging
output path. From Toshiaki Makita.
5) Several call sites of sk->sk_data_ready() were referencing an SKB
just added to the socket receive queue in order to calculate the
second argument via skb->len. This is dangerous because the moment
the skb is added to the receive queue it can be consumed in another
context and freed up.
It turns out also that none of the sk->sk_data_ready()
implementations even care about this second argument.
So just kill it off and thus fix all these use-after-free bugs as a
side effect.
6) Fix inverted test in tcp_v6_send_response(), from Lorenzo Colitti.
7) pktgen needs to do locking properly for LLTX devices, from Daniel
Borkmann.
8) xen-netfront driver initializes TX array entries in RX loop :-) From
Vincenzo Maffione.
9) After refactoring, some tunnel drivers allow a tunnel to be
configured on top itself. Fix from Nicolas Dichtel.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (46 commits)
vti: don't allow to add the same tunnel twice
gre: don't allow to add the same tunnel twice
drivers: net: xen-netfront: fix array initialization bug
pktgen: be friendly to LLTX devices
r8152: check RTL8152_UNPLUG
net: sun4i-emac: add promiscuous support
net/apne: replace IS_ERR and PTR_ERR with PTR_ERR_OR_ZERO
net: ipv6: Fix oif in TCP SYN+ACK route lookup.
drivers: net: cpsw: enable interrupts after napi enable and clearing previous interrupts
drivers: net: cpsw: discard all packets received when interface is down
net: Fix use after free by removing length arg from sk_data_ready callbacks.
Drivers: net: hyperv: Address UDP checksum issues
Drivers: net: hyperv: Negotiate suitable ndis version for offload support
Drivers: net: hyperv: Allocate memory for all possible per-pecket information
bridge: Fix double free and memory leak around br_allowed_ingress
bonding: Remove debug_fs files when module init fails
i40evf: program RSS LUT correctly
i40evf: remove open-coded skb_cow_head
ixgb: remove open-coded skb_cow_head
igbvf: remove open-coded skb_cow_head
...
The vfs merge caused a latent bug to show up:
In file included from fs/ceph/super.h:4:0,
from fs/ceph/ioctl.c:3:
include/linux/ceph/ceph_debug.h:4:0: warning: "pr_fmt" redefined [enabled by default]
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
^
In file included from include/linux/kernel.h:13:0,
from include/linux/uio.h:12,
from include/linux/socket.h:7,
from include/uapi/linux/in.h:22,
from include/linux/in.h:23,
from fs/ceph/ioctl.c:1:
include/linux/printk.h:214:0: note: this is the location of the previous definition
#define pr_fmt(fmt) fmt
^
where the reason is that <linux/ceph_debug.h> is included much too late
for the "pr_fmt()" define.
The include of <linux/ceph_debug.h> needs to be the first include in the
file, but fs/ceph/ioctl.c had for some reason missed that, and it wasn't
noticeable until some unrelated header file changes brought in an
indirect earlier include of <linux/kernel.h>.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
J. Bruce Fields