Commit Graph

53554 Commits

Author SHA1 Message Date
Ronnie Sahlberg 977b617040 cifs: remove rfc1002 header from all SMB2 response structures
Separate out all the 4 byte rfc1002 headers so that they are no longer
part of the SMB2 header structures to prepare for future work to add
compounding support.

Update the smb3 transform header processing that we no longer have
a rfc1002 header at the start of this structure.

Update smb2_readv_callback to accommodate that the first iovector in the
response is no the smb2 header and no longer a rfc1002 header.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-05-31 21:30:50 -05:00
Steve French b2adf22fdf smb3: on reconnect set PreviousSessionId field
The server detects reconnect by the (non-zero) value in PreviousSessionId
of SMB2/SMB3 SessionSetup request, but this behavior regressed due
to commit 166cea4dc3
("SMB2: Separate RawNTLMSSP authentication from SMB2_sess_setup")

CC: Stable <stable@vger.kernel.org>
CC: Sachin Prabhu <sprabhu@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-05-31 21:23:07 -05:00
Steve French ce558b0e17 smb3: Add posix create context for smb3.11 posix mounts
Signed-off-by: Steve French <smfrench@gmail.com>
2018-05-31 21:23:07 -05:00
Steve French 28d59363ae smb3: add tracepoints for smb2/smb3 open
add two tracepoints for open completion. One for error one for completion (open_done).
Sample output below

            TASK-PID   CPU#  ||||    TIMESTAMP  FUNCTION
               | |       |   ||||       |         |
            bash-15348 [007] .... 42441.027492: smb3_enter: 	cifs_lookup: xid=45
            bash-15348 [007] .... 42441.028214: smb3_cmd_err: 	sid=0x6173e4ce tid=0xa05150e6 cmd=5 mid=105 status=0xc0000034 rc=-2
            bash-15348 [007] .... 42441.028219: smb3_open_err: xid=45 sid=0x6173e4ce tid=0xa05150e6 cr_opts=0x0 des_access=0x80 rc=-2
            bash-15348 [007] .... 42441.028225: smb3_exit_done: 	cifs_lookup: xid=45
          fop777-24560 [002] .... 42442.627617: smb3_enter: 	cifs_revalidate_dentry_attr: xid=46
          fop777-24560 [003] .... 42442.628301: smb3_cmd_err: 	sid=0x6173e4ce tid=0xa05150e6 cmd=5 mid=106 status=0xc0000034 rc=-2
          fop777-24560 [003] .... 42442.628319: smb3_open_err: xid=46 sid=0x6173e4ce tid=0xa05150e6 cr_opts=0x0 des_access=0x80 rc=-2
          fop777-24560 [003] .... 42442.628335: smb3_enter: 	cifs_atomic_open: xid=47
          fop777-24560 [003] .... 42442.629587: smb3_cmd_done: 	sid=0x6173e4ce tid=0xa05150e6 cmd=5 mid=107
          fop777-24560 [003] .... 42442.629592: smb3_open_done: xid=47 sid=0x6173e4ce tid=0xa05150e6 fid=0xb8a0984d cr_opts=0x40 des_access=0x40000080

Signed-off-by: Steve French <smfrench@gmail.com>
2018-05-30 21:42:34 -05:00
Steve French 5c5a41be89 cifs: add debug output to show nocase mount option
For smb1 nocase can be specified on mount.  Allow displaying it
in debug data.

Signed-off-by: Steve French <smfrench@gmail.com>
2018-05-30 17:59:49 -05:00
Steve French fe048402e8 smb3: add define for id for posix create context and corresponding struct
Signed-off-by: Steve French <smfrench@gmail.com>
2018-05-30 17:59:46 -05:00
Ronnie Sahlberg 98170fb535 cifs: update smb2_check_message to handle PDUs without a 4 byte length header
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-05-30 17:24:14 -05:00
Steve French b326614ea2 smb3: allow "posix" mount option to enable new SMB311 protocol extensions
If "posix" (or synonym "unix" for backward compatibility) specified on mount,
and server advertises support for SMB3.11 POSIX negotiate context, then
enable the new posix extensions on the tcon.  This can be viewed by
looking for "posix" in the mount options displayed by /proc/mounts
for that mount (ie if posix extensions allowed by server and the
experimental POSIX extensions also requested on the mount by specifying
"posix" at mount time).

Also add check to warn user if conflicting unix/nounix or posix/noposix specified
on mount.

Signed-off-by: Steve French <smfrench@gmail.com>
2018-05-30 16:06:18 -05:00
Steve French fcef0db6d6 smb3: add support for posix negotiate context
Unlike CIFS where UNIX/POSIX extensions had been negotiatable,
SMB3 did not have POSIX extensions yet.  Add the new SMB3.11
POSIX negotiate context to ask the server whether it can
support POSIX (and thus whether we can send the new POSIX open
context).

Signed-off-by: Steve French <smfrench@gmail.com>
2018-05-30 16:06:18 -05:00
Steve French f92a720ee9 cifs: allow disabling less secure legacy dialects
To improve security it may be helpful to have additional ways to restrict the
ability to override the default dialects (SMB2.1, SMB3 and SMB3.02) on mount
with old dialects (CIFS/SMB1 and SMB2) since vers=1.0 (CIFS/SMB1) and vers=2.0
are weaker and less secure.

Add a module parameter "disable_legacy_dialects"
(/sys/module/cifs/parameters/disable_legacy_dialects) which can be set to
1 (or equivalently Y) to forbid use of vers=1.0 or vers=2.0 on mount.

Also cleans up a few build warnings about globals for various module parms.

Signed-off-by: Steve French <smfrench@gmail.com>
2018-05-30 16:06:18 -05:00
Steve French 11911b956f cifs: make minor clarifications to module params for cifs.ko
Note which ones of the module params are cifs dialect only
(N/A for default dialect now that has moved to SMB2.1 or later)

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-05-30 16:06:18 -05:00
Ronnie Sahlberg 6539e7f372 cifs: show the "w" bit for writeable /proc/fs/cifs/* files
RHBZ: 1539612

Lets show the "w" bit for those files have a .write interface to set/enable/...
the feature.

Reported-by: Xiaoli Feng <xifeng@redhat.com>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-05-30 16:06:18 -05:00
Steve French 49218b4f57 smb3: add module alias for smb3 to cifs.ko
We really don't want to be encouraging people to use the old
(less secure) cifs dialect (SMB1) and it can be confusing for them
with SMB3 (or later) being recommended but the module name is cifs.

Add a module alias for "smb3" to cifs.ko to make this less confusing.

Signed-off-by: Steve French <smfrench@gmail.com>
2018-05-30 16:06:18 -05:00
Ronnie Sahlberg 25ad1cbd02 cifs: return error on invalid value written to cifsFYI
RHBZ: 1539617

Check that, if it is not a boolean, the value the user tries
to write to /proc/fs/cifs/cifsFYI is valid and return an error
if not.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reported-by: Xiaoli Feng <xifeng@redhat.com>
2018-05-30 16:06:18 -05:00
Ronnie Sahlberg 57c55cd7c7 cifs: invalidate cache when we truncate a file
RHBZ: 1566345

When truncating a file we always do this synchronously to the server.
Thus we need to make sure that the cached inode metadata is
marked as stale so that on next getattr we will refresh the metadata.
In this particular bug we want to ensure that both ctime and mtime
are updated and become visible to the application after a truncate.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reported-by: Xiaoli Feng <xifeng@redhat.com>
2018-05-30 16:06:18 -05:00
Steve French e0386e449a smb3: print tree id in debugdata in proc to be able to help logging
When loooking at the logs for the new trace-cmd tracepoints for cifs,
it would help to know which tid is for which share (UNC name) so
update /proc/fs/cifs/DebugData to display the tid.
Also display Maximal Access which was missing as well.

Now the entry for typical entry for a tcon (in proc/fs/cifs/) looks
like:

1) \\localhost\test Mounts: 1 DevInfo: 0x20 Attributes: 0x1006f
	PathComponentMax: 255 Status: 1 type: DISK
	Share Capabilities: None Aligned, Partition Aligned,	Share Flags: 0x0
	tid: 0xe0632a55	Optimal sector size: 0x200	Maximal Access: 0x1f01ff

Signed-off-by: Steve French <smfrench@gmail.com>
2018-05-30 16:06:18 -05:00
Steve French d683bcd3e5 smb3: add additional ftrace entry points for entry/exit to cifs.ko
Signed-off-by: Steve French <smfrench@gmail.com>
2018-05-30 16:06:18 -05:00
Steve French cfe8909164 smb3: fix various xid leaks
Fix a few cases where we were not freeing the xid which led to
active requests being non-zero at unmount time.

Signed-off-by: Steve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-05-30 16:06:18 -05:00
Long Li 57a929a66f CIFS: Introduce offset for the 1st page in data transfer structures
When direct I/O is used, the data buffer may not always align to page
boundaries. Introduce a page offset in transport data structures to
describe the location of the buffer within the page.

Also change the function to pass the page offset when sending data to
transport.

Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-05-30 16:06:12 -05:00
Steve French eccb4422cf smb3: Add ftrace tracepoints for improved SMB3 debugging
Although dmesg logs and wireshark network traces can be
helpful, being able to dynamically enable/disable tracepoints
(in this case via the kernel ftrace mechanism) can also be
helpful in more quickly debugging problems, and more
selectively tracing the events related to the bug report.

This patch adds 12 ftrace tracepoints to cifs.ko for SMB3 events
in some obvious locations.  Subsequent patches will add more
as needed.

Example use:
   trace-cmd record -e cifs
   <run test case>
   trace-cmd show

Various trace events can be filtered. See:
       trace-cmd list | grep cifs
for the current list of cifs tracepoints.

Sample output (from mount and writing to a file):

root@smf:/sys/kernel/debug/tracing/events/cifs# trace-cmd show
<snip>
      mount.cifs-6633  [006] ....  7246.936461: smb3_cmd_done: pid=6633 tid=0x0 sid=0x0 cmd=0 mid=0
      mount.cifs-6633  [006] ....  7246.936701: smb3_cmd_err:  pid=6633 tid=0x0 sid=0x3d9cf8e5 cmd=1 mid=1 status=0xc0000016 rc=-5
      mount.cifs-6633  [006] ....  7246.943055: smb3_cmd_done: pid=6633 tid=0x0 sid=0x3d9cf8e5 cmd=1 mid=2
      mount.cifs-6633  [006] ....  7246.943298: smb3_cmd_done: pid=6633 tid=0xf9447636 sid=0x3d9cf8e5 cmd=3 mid=3
      mount.cifs-6633  [006] ....  7246.943446: smb3_cmd_done: pid=6633 tid=0xf9447636 sid=0x3d9cf8e5 cmd=11 mid=4
      mount.cifs-6633  [006] ....  7246.943659: smb3_cmd_done: pid=6633 tid=0xe1b781a sid=0x3d9cf8e5 cmd=3 mid=5
      mount.cifs-6633  [006] ....  7246.943766: smb3_cmd_done: pid=6633 tid=0xe1b781a sid=0x3d9cf8e5 cmd=11 mid=6
      mount.cifs-6633  [006] ....  7246.943937: smb3_cmd_done: pid=6633 tid=0xe1b781a sid=0x3d9cf8e5 cmd=5 mid=7
      mount.cifs-6633  [006] ....  7246.944020: smb3_cmd_done: pid=6633 tid=0xe1b781a sid=0x3d9cf8e5 cmd=16 mid=8
      mount.cifs-6633  [006] ....  7246.944091: smb3_cmd_done: pid=6633 tid=0xe1b781a sid=0x3d9cf8e5 cmd=16 mid=9
      mount.cifs-6633  [006] ....  7246.944163: smb3_cmd_done: pid=6633 tid=0xe1b781a sid=0x3d9cf8e5 cmd=16 mid=10
      mount.cifs-6633  [006] ....  7246.944218: smb3_cmd_err:  pid=6633 tid=0xf9447636 sid=0x3d9cf8e5 cmd=11 mid=11 status=0xc0000225 rc=-2
      mount.cifs-6633  [006] ....  7246.944219: smb3_fsctl_err: xid=0 fid=0xffffffffffffffff tid=0xf9447636 sid=0x3d9cf8e5 class=0 type=393620 rc=-2
      mount.cifs-6633  [007] ....  7246.944353: smb3_cmd_done: pid=6633 tid=0xe1b781a sid=0x3d9cf8e5 cmd=16 mid=12
            bash-2071  [000] ....  7256.903844: smb3_cmd_done: pid=2071 tid=0xe1b781a sid=0x3d9cf8e5 cmd=5 mid=13
            bash-2071  [000] ....  7256.904172: smb3_cmd_done: pid=2071 tid=0xe1b781a sid=0x3d9cf8e5 cmd=16 mid=14
            bash-2071  [000] ....  7256.904471: smb3_cmd_done: pid=2071 tid=0xe1b781a sid=0x3d9cf8e5 cmd=17 mid=15
            bash-2071  [000] ....  7256.904950: smb3_cmd_done: pid=2071 tid=0xe1b781a sid=0x3d9cf8e5 cmd=5 mid=16
            bash-2071  [000] ....  7256.905305: smb3_cmd_done: pid=2071 tid=0xe1b781a sid=0x3d9cf8e5 cmd=17 mid=17
            bash-2071  [000] ....  7256.905688: smb3_cmd_done: pid=2071 tid=0xe1b781a sid=0x3d9cf8e5 cmd=6 mid=18
            bash-2071  [000] ....  7256.905809: smb3_write_done: xid=0 fid=0xd628f511 tid=0xe1b781a sid=0x3d9cf8e5 offset=0x0 len=0x1b

Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-05-27 17:56:35 -05:00
Steve French 5a77e75fed smb3: rename encryption_required to smb3_encryption_required
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2018-05-27 17:56:35 -05:00
Steve French 3fa9a54061 cifs: update internal module version number for cifs.ko to 2.12
Signed-off-by: Steve French <smfrench@gmail.com>
2018-05-27 17:56:35 -05:00
Ronnie Sahlberg 97ca176224 cifs: add a new SMB2_close_flags function
And make SMB2_close just a wrapper for SMB2_close_flags.
We need this as we will start to send SMB2_CLOSE pdus using special
flags.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2018-05-27 17:56:35 -05:00
Ronnie Sahlberg 96164ab2d8 cifs: store the leaseKey in the fid on SMB2_open
In SMB2_open(), if we got a lease we need to store this in the fid structure
or else we will never be able to map a lease break back to which file/fid
it applies to.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2018-05-27 17:56:35 -05:00
Steve French 71992e62b8 cifs: fix build break when CONFIG_CIFS_DEBUG2 enabled
Previous patches "cifs: update calc_size to take a server argument"
and
  "cifs: add server argument to the dump_detail method"
were broken if CONFIG_CIFS_DEBUG2 enabled

Signed-off-by: Steve French <smfrench@gmail.com>
CC: Ronnie Sahlberg <lsahlber@redhat.com>
2018-05-27 17:56:35 -05:00
Ronnie Sahlberg 9ec672bd17 cifs: update calc_size to take a server argument
and change the smb2 version to take heder_preamble_size into account
instead of hardcoding it as 4 bytes.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2018-05-27 17:56:35 -05:00
Ronnie Sahlberg 14547f7d74 cifs: add server argument to the dump_detail method
We need a struct TCP_Server_Info *server to this method as it calls
calc_size. The calc_size method will soon be changed to also
take a server argument.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2018-05-27 17:56:35 -05:00
Steve French 3d4ef9a153 smb3: fix redundant opens on root
In SMB2/SMB3 unlike in cifs we unnecessarily open the root of the share
over and over again in various places during mount and path revalidation
and also in statfs.  This patch cuts redundant traffic (opens and closes)
by simply keeping the directory handle for the root around (and reopening
it as needed on reconnect), so query calls don't require three round
trips to copmlete - just one, and eases load on network, client and
server (on mount alone, cuts network traffic by more than a third).

Also add a new cifs mount parm "nohandlecache" to allow users whose
servers might have resource constraints (eg in case they have a server
with so many users connecting to it that this extra handle per mount
could possibly be a resource concern).

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-05-27 17:56:35 -05:00
Hugh Dickins 6c04ab0edd proc: fix smaps and meminfo alignment
The 4.17-rc /proc/meminfo and /proc/<pid>/smaps look ugly: single-digit
numbers (commonly 0) are misaligned.

Remove seq_put_decimal_ull_width()'s leftover optimization for single
digits: it's wrong now that num_to_str() takes care of the width.

Link: http://lkml.kernel.org/r/alpine.LSU.2.11.1805241554210.1326@eggly.anvils
Fixes: d1be35cb6f ("proc: add seq_put_decimal_ull_width to speed up /proc/pid/smaps")
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Andrei Vagin <avagin@openvz.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-05-25 18:12:11 -07:00
Changwei Ge 3373de209c ocfs2: revert "ocfs2/o2hb: check len for bio_add_page() to avoid getting incorrect bio"
This reverts commit ba16ddfbeb ("ocfs2/o2hb: check len for
bio_add_page() to avoid getting incorrect bio").

In my testing, this patch introduces a problem that mkfs can't have
slots more than 16 with 4k block size.

And the original logic is safe actually with the situation it mentions
so revert this commit.

Attach test log:
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 0, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 1, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 2, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 3, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 4, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 5, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 6, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 7, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 8, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 9, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 10, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 11, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 12, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 13, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 14, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 15, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:463 page 16, vec_len = 4096, vec_start = 0
  (mkfs.ocfs2,27479,2):o2hb_setup_one_bio:471 ERROR: Adding page[16] to bio failed, page ffffea0002d7ed40, len 0, vec_len 4096, vec_start 0,bi_sector 8192
  (mkfs.ocfs2,27479,2):o2hb_read_slots:500 ERROR: status = -5
  (mkfs.ocfs2,27479,2):o2hb_populate_slot_data:1911 ERROR: status = -5
  (mkfs.ocfs2,27479,2):o2hb_region_dev_write:2012 ERROR: status = -5

Link: http://lkml.kernel.org/r/SIXPR06MB0461721F398A5A92FC68C39ED5920@SIXPR06MB0461.apcprd06.prod.outlook.com
Signed-off-by: Changwei Ge <ge.changwei@h3c.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Yiwen Jiang <jiangyiwen@huawei.com>
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-05-25 18:12:10 -07:00
Linus Torvalds 34b48b8789 Merge candidates for 4.17-rc
- Remove bouncing addresses from the MAINTAINERS file
 - Kernel oops and bad error handling fixes for hfi, i40iw, cxgb4, and hns drivers
 - Various small LOC behavioral/operational bugs in mlx5, hns, qedr and i40iw drivers
 - Two fixes for patches already sent during the merge window
 - A long standing bug related to not decreasing the pinned pages count in the right
   MM was found and fixed
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

Pull rdma fixes from Jason Gunthorpe:
 "This is pretty much just the usual array of smallish driver bugs.

   - remove bouncing addresses from the MAINTAINERS file

   - kernel oops and bad error handling fixes for hfi, i40iw, cxgb4, and
     hns drivers

   - various small LOC behavioral/operational bugs in mlx5, hns, qedr
     and i40iw drivers

   - two fixes for patches already sent during the merge window

   - a long-standing bug related to not decreasing the pinned pages
     count in the right MM was found and fixed"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (28 commits)
  RDMA/hns: Move the location for initializing tmp_len
  RDMA/hns: Bugfix for cq record db for kernel
  IB/uverbs: Fix uverbs_attr_get_obj
  RDMA/qedr: Fix doorbell bar mapping for dpi > 1
  IB/umem: Use the correct mm during ib_umem_release
  iw_cxgb4: Fix an error handling path in 'c4iw_get_dma_mr()'
  RDMA/i40iw: Avoid panic when reading back the IRQ affinity hint
  RDMA/i40iw: Avoid reference leaks when processing the AEQ
  RDMA/i40iw: Avoid panic when objects are being created and destroyed
  RDMA/hns: Fix the bug with NULL pointer
  RDMA/hns: Set NULL for __internal_mr
  RDMA/hns: Enable inner_pa_vld filed of mpt
  RDMA/hns: Set desc_dma_addr for zero when free cmq desc
  RDMA/hns: Fix the bug with rq sge
  RDMA/hns: Not support qp transition from reset to reset for hip06
  RDMA/hns: Add return operation when configured global param fail
  RDMA/hns: Update convert function of endian format
  RDMA/hns: Load the RoCE dirver automatically
  RDMA/hns: Bugfix for rq record db for kernel
  RDMA/hns: Add rq inline flags judgement
  ...
2018-05-24 14:12:05 -07:00
Linus Torvalds d7b66b4ab0 for-4.17-rc6-tag
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Merge tag 'for-4.17-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fix from David Sterba:
 "A one-liner that prevents leaking an internal error value 1 out of the
  ftruncate syscall.

  This has been observed in practice. The steps to reproduce make a
  common pattern (open/write/fync/ftruncate) but also need the
  application to not check only for negative values and happens only for
  compressed inlined files.

  The conditions are narrow but as this could break userspace I think
  it's better to merge it now and not wait for the merge window"

* tag 'for-4.17-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  Btrfs: fix error handling in btrfs_truncate()
2018-05-24 11:47:43 -07:00
Omar Sandoval d50147381a Btrfs: fix error handling in btrfs_truncate()
Jun Wu at Facebook reported that an internal service was seeing a return
value of 1 from ftruncate() on Btrfs in some cases. This is coming from
the NEED_TRUNCATE_BLOCK return value from btrfs_truncate_inode_items().

btrfs_truncate() uses two variables for error handling, ret and err.
When btrfs_truncate_inode_items() returns non-zero, we set err to the
return value. However, NEED_TRUNCATE_BLOCK is not an error. Make sure we
only set err if ret is an error (i.e., negative).

To reproduce the issue: mount a filesystem with -o compress-force=zstd
and the following program will encounter return value of 1 from
ftruncate:

int main(void) {
        char buf[256] = { 0 };
        int ret;
        int fd;

        fd = open("test", O_CREAT | O_WRONLY | O_TRUNC, 0666);
        if (fd == -1) {
                perror("open");
                return EXIT_FAILURE;
        }

        if (write(fd, buf, sizeof(buf)) != sizeof(buf)) {
                perror("write");
                close(fd);
                return EXIT_FAILURE;
        }

        if (fsync(fd) == -1) {
                perror("fsync");
                close(fd);
                return EXIT_FAILURE;
        }

        ret = ftruncate(fd, 128);
        if (ret) {
                printf("ftruncate() returned %d\n", ret);
                close(fd);
                return EXIT_FAILURE;
        }

        close(fd);
        return EXIT_SUCCESS;
}

Fixes: ddfae63cc8 ("btrfs: move btrfs_truncate_block out of trans handle")
CC: stable@vger.kernel.org # 4.15+
Reported-by: Jun Wu <quark@fb.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-24 11:56:57 +02:00
Linus Torvalds 5997aab0a1 Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro:
 "Assorted fixes all over the place"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  aio: fix io_destroy(2) vs. lookup_ioctx() race
  ext2: fix a block leak
  nfsd: vfs_mkdir() might succeed leaving dentry negative unhashed
  cachefiles: vfs_mkdir() might succeed leaving dentry negative unhashed
  unfuck sysfs_mount()
  kernfs: deal with kernfs_fill_super() failures
  cramfs: Fix IS_ENABLED typo
  befs_lookup(): use d_splice_alias()
  affs_lookup: switch to d_splice_alias()
  affs_lookup(): close a race with affs_remove_link()
  fix breakage caused by d_find_alias() semantics change
  fs: don't scan the inode cache before SB_BORN is set
  do d_instantiate/unlock_new_inode combinations safely
  iov_iter: fix memory leak in pipe_get_pages_alloc()
  iov_iter: fix return type of __pipe_get_pages()
2018-05-21 11:54:57 -07:00
Al Viro baf10564fb aio: fix io_destroy(2) vs. lookup_ioctx() race
kill_ioctx() used to have an explicit RCU delay between removing the
reference from ->ioctx_table and percpu_ref_kill() dropping the refcount.
At some point that delay had been removed, on the theory that
percpu_ref_kill() itself contained an RCU delay.  Unfortunately, that was
the wrong kind of RCU delay and it didn't care about rcu_read_lock() used
by lookup_ioctx().  As the result, we could get ctx freed right under
lookup_ioctx().  Tejun has fixed that in a6d7cff472 ("fs/aio: Add explicit
RCU grace period when freeing kioctx"); however, that fix is not enough.

Suppose io_destroy() from one thread races with e.g. io_setup() from another;
CPU1 removes the reference from current->mm->ioctx_table[...] just as CPU2
has picked it (under rcu_read_lock()).  Then CPU1 proceeds to drop the
refcount, getting it to 0 and triggering a call of free_ioctx_users(),
which proceeds to drop the secondary refcount and once that reaches zero
calls free_ioctx_reqs().  That does
        INIT_RCU_WORK(&ctx->free_rwork, free_ioctx);
        queue_rcu_work(system_wq, &ctx->free_rwork);
and schedules freeing the whole thing after RCU delay.

In the meanwhile CPU2 has gotten around to percpu_ref_get(), bumping the
refcount from 0 to 1 and returned the reference to io_setup().

Tejun's fix (that queue_rcu_work() in there) guarantees that ctx won't get
freed until after percpu_ref_get().  Sure, we'd increment the counter before
ctx can be freed.  Now we are out of rcu_read_lock() and there's nothing to
stop freeing of the whole thing.  Unfortunately, CPU2 assumes that since it
has grabbed the reference, ctx is *NOT* going away until it gets around to
dropping that reference.

The fix is obvious - use percpu_ref_tryget_live() and treat failure as miss.
It's not costlier than what we currently do in normal case, it's safe to
call since freeing *is* delayed and it closes the race window - either
lookup_ioctx() comes before percpu_ref_kill() (in which case ctx->users
won't reach 0 until the caller of lookup_ioctx() drops it) or lookup_ioctx()
fails, ctx->users is unaffected and caller of lookup_ioctx() doesn't see
the object in question at all.

Cc: stable@kernel.org
Fixes: a6d7cff472 "fs/aio: Add explicit RCU grace period when freeing kioctx"
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-21 14:30:11 -04:00
Al Viro 5aa1437d2d ext2: fix a block leak
open file, unlink it, then use ioctl(2) to make it immutable or
append only.  Now close it and watch the blocks *not* freed...

Immutable/append-only checks belong in ->setattr().
Note: the bug is old and backport to anything prior to 737f2e93b9
("ext2: convert to use the new truncate convention") will need
these checks lifted into ext2_setattr().

Cc: stable@kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-21 14:30:11 -04:00
Al Viro 3819bb0d79 nfsd: vfs_mkdir() might succeed leaving dentry negative unhashed
That can (and does, on some filesystems) happen - ->mkdir() (and thus
vfs_mkdir()) can legitimately leave its argument negative and just
unhash it, counting upon the lookup to pick the object we'd created
next time we try to look at that name.

Some vfs_mkdir() callers forget about that possibility...

Acked-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-21 14:30:10 -04:00
Al Viro 9c3e9025a3 cachefiles: vfs_mkdir() might succeed leaving dentry negative unhashed
That can (and does, on some filesystems) happen - ->mkdir() (and thus
vfs_mkdir()) can legitimately leave its argument negative and just
unhash it, counting upon the lookup to pick the object we'd created
next time we try to look at that name.

Some vfs_mkdir() callers forget about that possibility...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-21 14:30:10 -04:00
Al Viro 7b745a4e40 unfuck sysfs_mount()
new_sb is left uninitialized in case of early failures in kernfs_mount_ns(),
and while IS_ERR(root) is true in all such cases, using IS_ERR(root) || !new_sb
is not a solution - IS_ERR(root) is true in some cases when new_sb is true.

Make sure new_sb is initialized (and matches the reality) in all cases and
fix the condition for dropping kobj reference - we want it done precisely
in those situations where the reference has not been transferred into a new
super_block instance.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-21 14:30:09 -04:00
Al Viro 82382acec0 kernfs: deal with kernfs_fill_super() failures
make sure that info->node is initialized early, so that kernfs_kill_sb()
can list_del() it safely.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-21 14:30:08 -04:00
Joe Perches 08a8f30868 cramfs: Fix IS_ENABLED typo
There's an extra C here...

Fixes: 99c18ce580 ("cramfs: direct memory access support")
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-21 14:30:08 -04:00
Al Viro f4e4d434fe befs_lookup(): use d_splice_alias()
RTFS(Documentation/filesystems/nfs/Exporting) if you try to make
something exportable.

Fixes: ac632f5b63 "befs: add NFS export support"
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-21 14:30:07 -04:00
Al Viro 87fbd639c0 affs_lookup: switch to d_splice_alias()
Making something exportable takes more than providing ->s_export_ops.
In particular, ->lookup() *MUST* use d_splice_alias() instead of
d_add().

Reading Documentation/filesystems/nfs/Exporting would've been a good idea;
as it is, exporting AFFS is badly (and exploitably) broken.

Partially-Fixes: ed4433d723 "fs/affs: make affs exportable"
Acked-by: David Sterba <dsterba@suse.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-21 14:29:12 -04:00
Al Viro 30da870ce4 affs_lookup(): close a race with affs_remove_link()
we unlock the directory hash too early - if we are looking at secondary
link and primary (in another directory) gets removed just as we unlock,
we could have the old primary moved in place of the secondary, leaving
us to look into freed entry (and leaving our dentry with ->d_fsdata
pointing to a freed entry).

Cc: stable@vger.kernel.org # 2.4.4+
Acked-by: David Sterba <dsterba@suse.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-21 14:27:45 -04:00
Linus Torvalds 3b78ce4a34 Merge branch 'speck-v20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Merge speculative store buffer bypass fixes from Thomas Gleixner:

 - rework of the SPEC_CTRL MSR management to accomodate the new fancy
   SSBD (Speculative Store Bypass Disable) bit handling.

 - the CPU bug and sysfs infrastructure for the exciting new Speculative
   Store Bypass 'feature'.

 - support for disabling SSB via LS_CFG MSR on AMD CPUs including
   Hyperthread synchronization on ZEN.

 - PRCTL support for dynamic runtime control of SSB

 - SECCOMP integration to automatically disable SSB for sandboxed
   processes with a filter flag for opt-out.

 - KVM integration to allow guests fiddling with SSBD including the new
   software MSR VIRT_SPEC_CTRL to handle the LS_CFG based oddities on
   AMD.

 - BPF protection against SSB

.. this is just the core and x86 side, other architecture support will
come separately.

* 'speck-v20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (49 commits)
  bpf: Prevent memory disambiguation attack
  x86/bugs: Rename SSBD_NO to SSB_NO
  KVM: SVM: Implement VIRT_SPEC_CTRL support for SSBD
  x86/speculation, KVM: Implement support for VIRT_SPEC_CTRL/LS_CFG
  x86/bugs: Rework spec_ctrl base and mask logic
  x86/bugs: Remove x86_spec_ctrl_set()
  x86/bugs: Expose x86_spec_ctrl_base directly
  x86/bugs: Unify x86_spec_ctrl_{set_guest,restore_host}
  x86/speculation: Rework speculative_store_bypass_update()
  x86/speculation: Add virtualized speculative store bypass disable support
  x86/bugs, KVM: Extend speculation control for VIRT_SPEC_CTRL
  x86/speculation: Handle HT correctly on AMD
  x86/cpufeatures: Add FEATURE_ZEN
  x86/cpufeatures: Disentangle SSBD enumeration
  x86/cpufeatures: Disentangle MSR_SPEC_CTRL enumeration from IBRS
  x86/speculation: Use synthetic bits for IBRS/IBPB/STIBP
  KVM: SVM: Move spec control call after restore of GS
  x86/cpu: Make alternative_msr_write work for 32-bit code
  x86/bugs: Fix the parameters alignment and missing void
  x86/bugs: Make cpu_show_common() static
  ...
2018-05-21 11:23:26 -07:00
Linus Torvalds e5e03ad9e0 for-4.17-rc5-tag
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Merge tag 'for-4.17-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "We've accumulated some fixes during the last week, some of them were
  in the works for a longer time but there are some newer ones too.

  Most of the fixes have a reproducer and fix user visible problems,
  also candidates for stable kernels. They IMHO qualify for a late rc,
  though I did not expect that many"

* tag 'for-4.17-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: fix crash when trying to resume balance without the resume flag
  btrfs: Fix delalloc inodes invalidation during transaction abort
  btrfs: Split btrfs_del_delalloc_inode into 2 functions
  btrfs: fix reading stale metadata blocks after degraded raid1 mounts
  btrfs: property: Set incompat flag if lzo/zstd compression is set
  Btrfs: fix duplicate extents after fsync of file with prealloc extents
  Btrfs: fix xattr loss after power failure
  Btrfs: send, fix invalid access to commit roots due to concurrent snapshotting
2018-05-20 12:04:27 -07:00
Tetsuo Handa 66072c2932 hfsplus: stop workqueue when fill_super() failed
syzbot is reporting ODEBUG messages at hfsplus_fill_super() [1].  This
is because hfsplus_fill_super() forgot to call cancel_delayed_work_sync().

As far as I can see, it is hfsplus_mark_mdb_dirty() from
hfsplus_new_inode() in hfsplus_fill_super() that calls
queue_delayed_work().  Therefore, I assume that hfsplus_new_inode() does
not fail if queue_delayed_work() was called, and the out_put_hidden_dir
label is the appropriate location to call cancel_delayed_work_sync().

[1] https://syzkaller.appspot.com/bug?id=a66f45e96fdbeb76b796bf46eb25ea878c42a6c9

Link: http://lkml.kernel.org/r/964a8b27-cd69-357c-fe78-76b066056201@I-love.SAKURA.ne.jp
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: syzbot <syzbot+4f2e5f086147d543ab03@syzkaller.appspotmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: David Howells <dhowells@redhat.com>
Cc: Ernesto A. Fernandez <ernesto.mnd.fernandez@gmail.com>
Cc: Vyacheslav Dubeyko <slava@dubeyko.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-05-18 17:17:12 -07:00
Willy Tarreau 7f7ccc2ccc proc: do not access cmdline nor environ from file-backed areas
proc_pid_cmdline_read() and environ_read() directly access the target
process' VM to retrieve the command line and environment. If this
process remaps these areas onto a file via mmap(), the requesting
process may experience various issues such as extra delays if the
underlying device is slow to respond.

Let's simply refuse to access file-backed areas in these functions.
For this we add a new FOLL_ANON gup flag that is passed to all calls
to access_remote_vm(). The code already takes care of such failures
(including unmapped areas). Accesses via /proc/pid/mem were not
changed though.

This was assigned CVE-2018-1120.

Note for stable backports: the patch may apply to kernels prior to 4.11
but silently miss one location; it must be checked that no call to
access_remote_vm() keeps zero as the last argument.

Reported-by: Qualys Security Advisory <qsa@qualys.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-05-17 09:27:47 -07:00
Anand Jain 02ee654d3a btrfs: fix crash when trying to resume balance without the resume flag
We set the BTRFS_BALANCE_RESUME flag in the btrfs_recover_balance()
only, which isn't called during the remount. So when resuming from
the paused balance we hit the bug:

 kernel: kernel BUG at fs/btrfs/volumes.c:3890!
 ::
 kernel:  balance_kthread+0x51/0x60 [btrfs]
 kernel:  kthread+0x111/0x130
 ::
 kernel: RIP: btrfs_balance+0x12e1/0x1570 [btrfs] RSP: ffffba7d0090bde8

Reproducer:
  On a mounted filesystem:

  btrfs balance start --full-balance /btrfs
  btrfs balance pause /btrfs
  mount -o remount,ro /dev/sdb /btrfs
  mount -o remount,rw /dev/sdb /btrfs

To fix this set the BTRFS_BALANCE_RESUME flag in
btrfs_resume_balance_async().

CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-17 14:38:24 +02:00
Nikolay Borisov fe816d0f1d btrfs: Fix delalloc inodes invalidation during transaction abort
When a transaction is aborted btrfs_cleanup_transaction is called to
cleanup all the various in-flight bits and pieces which migth be
active. One of those is delalloc inodes - inodes which have dirty
pages which haven't been persisted yet. Currently the process of
freeing such delalloc inodes in exceptional circumstances such as
transaction abort boiled down to calling btrfs_invalidate_inodes whose
sole job is to invalidate the dentries for all inodes related to a
root. This is in fact wrong and insufficient since such delalloc inodes
will likely have pending pages or ordered-extents and will be linked to
the sb->s_inode_list. This means that unmounting a btrfs instance with
an aborted transaction could potentially lead inodes/their pages
visible to the system long after their superblock has been freed. This
in turn leads to a "use-after-free" situation once page shrink is
triggered. This situation could be simulated by running generic/019
which would cause such inodes to be left hanging, followed by
generic/176 which causes memory pressure and page eviction which lead
to touching the freed super block instance. This situation is
additionally detected by the unmount code of VFS with the following
message:

"VFS: Busy inodes after unmount of Self-destruct in 5 seconds.  Have a nice day..."

Additionally btrfs hits WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
in free_fs_root for the same reason.

This patch aims to rectify the sitaution by doing the following:

1. Change btrfs_destroy_delalloc_inodes so that it calls
invalidate_inode_pages2 for every inode on the delalloc list, this
ensures that all the pages of the inode are released. This function
boils down to calling btrfs_releasepage. During test I observed cases
where inodes on the delalloc list were having an i_count of 0, so this
necessitates using igrab to be sure we are working on a non-freed inode.

2. Since calling btrfs_releasepage might queue delayed iputs move the
call out to btrfs_cleanup_transaction in btrfs_error_commit_super before
calling run_delayed_iputs for the last time. This is necessary to ensure
that delayed iputs are run.

Note: this patch is tagged for 4.14 stable but the fix applies to older
versions too but needs to be backported manually due to conflicts.

CC: stable@vger.kernel.org # 4.14.x: 2b8773313494: btrfs: Split btrfs_del_delalloc_inode into 2 functions
CC: stable@vger.kernel.org # 4.14.x
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add comment to igrab ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-17 14:38:18 +02:00