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50869 commits

Author SHA1 Message Date
David S. Miller
ed29668d1a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Smooth Cong Wang's bug fix into 'net-next'.  Basically put
the bulk of the tcf_block_put() logic from 'net' into
tcf_block_put_ext(), but after the offload unbind.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-02 15:23:39 +09:00
David S. Miller
e1ea2f9856 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Several conflicts here.

NFP driver bug fix adding nfp_netdev_is_nfp_repr() check to
nfp_fl_output() needed some adjustments because the code block is in
an else block now.

Parallel additions to net/pkt_cls.h and net/sch_generic.h

A bug fix in __tcp_retransmit_skb() conflicted with some of
the rbtree changes in net-next.

The tc action RCU callback fixes in 'net' had some overlap with some
of the recent tcf_block reworking.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-30 21:09:24 +09:00
Ronnie Sahlberg
f74bc7c667 cifs: check MaxPathNameComponentLength != 0 before using it
And fix tcon leak in error path.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: David Disseldorp <ddiss@samba.org>
2017-10-30 02:11:38 -05:00
Linus Torvalds
7814023404 Various SMB3 fixes for 4.14 and stable
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Merge tag '4.14-smb3-fixes-for-stable' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs fixes from Steve French:
 "Various SMB3 fixes for 4.14 and stable"

* tag '4.14-smb3-fixes-for-stable' of git://git.samba.org/sfrench/cifs-2.6:
  SMB3: Validate negotiate request must always be signed
  SMB: fix validate negotiate info uninitialised memory use
  SMB: fix leak of validate negotiate info response buffer
  CIFS: Fix NULL pointer deref on SMB2_tcon() failure
  CIFS: do not send invalid input buffer on QUERY_INFO requests
  cifs: Select all required crypto modules
  CIFS: SMBD: Fix the definition for SMB2_CHANNEL_RDMA_V1_INVALIDATE
  cifs: handle large EA requests more gracefully in smb2+
  Fix encryption labels and lengths for SMB3.1.1
2017-10-28 08:39:35 -07:00
Linus Torvalds
c9f27f9f85 Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull overlayfs fixes from Miklos Szeredi:
 "Fix several issues, most of them introduced in the last release"

* 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  ovl: do not cleanup unsupported index entries
  ovl: handle ENOENT on index lookup
  ovl: fix EIO from lookup of non-indexed upper
  ovl: Return -ENOMEM if an allocation fails ovl_lookup()
  ovl: add NULL check in ovl_alloc_inode
2017-10-28 08:29:29 -07:00
Linus Torvalds
a9af9835d3 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse fix from Miklos Szeredi:
 "This fixes a longstanding bug, which can be triggered by interrupting
  a directory reading syscall"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: fix READDIRPLUS skipping an entry
2017-10-28 08:27:46 -07:00
Steve French
4587eee04e SMB3: Validate negotiate request must always be signed
According to MS-SMB2 3.2.55 validate_negotiate request must
always be signed. Some Windows can fail the request if you send it unsigned

See kernel bugzilla bug 197311

CC: Stable <stable@vger.kernel.org>
Acked-by: Ronnie Sahlberg <lsahlber.redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2017-10-26 12:20:59 -05:00
Linus Torvalds
601c5c2ee9 A small lock imbalance fix, marked for stable.
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Merge tag 'ceph-for-4.14-rc7' of git://github.com/ceph/ceph-client

Pull ceph fix from Ilya Dryomov:
 "A small lock imbalance fix, marked for stable"

* tag 'ceph-for-4.14-rc7' of git://github.com/ceph/ceph-client:
  ceph: unlock dangling spinlock in try_flush_caps()
2017-10-26 17:04:20 +02:00
Linus Torvalds
4ed590271a Changes since last time:
- Rework nowait locking code to reduce locking overhead penalty
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Merge tag 'xfs-4.14-fixes-7' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs fix from Darrick Wong:
 "Here's (hopefully) the last bugfix for 4.14:

   - Rework nowait locking code to reduce locking overhead penalty"

* tag 'xfs-4.14-fixes-7' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: fix AIM7 regression
2017-10-26 08:45:40 +02:00
David Disseldorp
a2d9daad1d SMB: fix validate negotiate info uninitialised memory use
An undersize validate negotiate info server response causes the client
to use uninitialised memory for struct validate_negotiate_info_rsp
comparisons of Dialect, SecurityMode and/or Capabilities members.

Link: https://bugzilla.samba.org/show_bug.cgi?id=13092
Fixes: 7db0a6efdc ("SMB3: Work around mount failure when using SMB3 dialect to Macs")
Signed-off-by: David Disseldorp <ddiss@suse.de>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2017-10-25 13:04:25 -05:00
David Disseldorp
fe83bebc05 SMB: fix leak of validate negotiate info response buffer
Fixes: ff1c038add ("Check SMB3 dialects against downgrade attacks")
Signed-off-by: David Disseldorp <ddiss@suse.de>
Signed-off-by: Steve French <smfrench@gmail.com>
2017-10-25 13:02:59 -05:00
Aurélien Aptel
db3b5474f4 CIFS: Fix NULL pointer deref on SMB2_tcon() failure
If SendReceive2() fails rsp is set to NULL but is dereferenced in the
error handling code.

Cc: stable@vger.kernel.org
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2017-10-25 12:58:54 -05:00
Aurelien Aptel
48923d2a9d CIFS: do not send invalid input buffer on QUERY_INFO requests
query_info() doesn't use the InputBuffer field of the QUERY_INFO
request, therefore according to [MS-SMB2] it must:

a) set the InputBufferOffset to 0
b) send a zero-length InputBuffer

Doing a) is trivial but b) is a bit more tricky.

The packet is allocated according to it's StructureSize, which takes
into account an extra 1 byte buffer which we don't need
here. StructureSize fields must have constant values no matter the
actual length of the whole packet so we can't just edit that constant.

Both the NetBIOS-over-TCP message length ("rfc1002 length") L and the
iovec length L' have to be updated. Since L' is computed from L we
just update L by decrementing it by one.

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2017-10-25 12:57:57 -05:00
Benjamin Gilbert
5b454a6455 cifs: Select all required crypto modules
Some dependencies were lost when CIFS_SMB2 was merged into CIFS.

Fixes: 2a38e12053 ("[SMB3] Remove ifdef since SMB3 (and later) now STRONGLY preferred")
Signed-off-by: Benjamin Gilbert <benjamin.gilbert@coreos.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <smfrench@gmail.com>
2017-10-25 12:57:50 -05:00
Miklos Szeredi
c6cdd51404 fuse: fix READDIRPLUS skipping an entry
Marios Titas running a Haskell program noticed a problem with fuse's
readdirplus: when it is interrupted by a signal, it skips one directory
entry.

The reason is that fuse erronously updates ctx->pos after a failed
dir_emit().

The issue originates from the patch adding readdirplus support.

Reported-by: Jakob Unterwurzacher <jakobunt@gmail.com>
Tested-by: Marios Titas <redneb@gmx.com> 
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 0b05b18381 ("fuse: implement NFS-like readdirplus support")
Cc: <stable@vger.kernel.org> # v3.9
2017-10-25 16:34:27 +02:00
Jeff Layton
6c2838fbde ceph: unlock dangling spinlock in try_flush_caps()
sparse warns:

  fs/ceph/caps.c:2042:9: warning: context imbalance in 'try_flush_caps' - wrong count at exit

We need to exit this function with the lock unlocked, but a couple of
cases leave it locked.

Cc: stable@vger.kernel.org
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-10-25 08:31:15 +02:00
Amir Goldstein
fa0096e3ba ovl: do not cleanup unsupported index entries
With index=on, ovl_indexdir_cleanup() tries to cleanup invalid index
entries (e.g. bad index name). This behavior could result in cleaning of
entries created by newer kernels and is therefore undesirable.
Instead, abort mount if such entries are encountered. We still cleanup
'stale' entries and 'orphan' entries, both those cases can be a result
of offline changes to lower and upper dirs.

When encoutering an index entry of type directory or whiteout, kernel
was supposed to fallback to read-only mount, but the fill_super()
operation returns EROFS in this case instead of returning success with
read-only mount flag, so mount fails when encoutering directory or
whiteout index entries. Bless this behavior by returning -EINVAL on
directory and whiteout index entries as we do for all unsupported index
entries.

Fixes: 61b674710c ("ovl: do not cleanup directory and whiteout index..")
Cc: <stable@vger.kernel.org> # v4.13
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
2017-10-24 16:06:17 +02:00
Amir Goldstein
7937a56fdf ovl: handle ENOENT on index lookup
Treat ENOENT from index entry lookup the same way as treating a returned
negative dentry. Apparently, either could be returned if file is not
found, depending on the underlying file system.

Fixes: 359f392ca5 ("ovl: lookup index entry for copy up origin")
Cc: <stable@vger.kernel.org> # v4.13
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
2017-10-24 16:06:17 +02:00
Amir Goldstein
6eaf011144 ovl: fix EIO from lookup of non-indexed upper
Commit fbaf94ee3c ("ovl: don't set origin on broken lower hardlink")
attempt to avoid the condition of non-indexed upper inode with lower
hardlink as origin. If this condition is found, lookup returns EIO.

The protection of commit mentioned above does not cover the case of lower
that is not a hardlink when it is copied up (with either index=off/on)
and then lower is hardlinked while overlay is offline.

Changes to lower layer while overlayfs is offline should not result in
unexpected behavior, so a permanent EIO error after creating a link in
lower layer should not be considered as correct behavior.

This fix replaces EIO error with success in cases where upper has origin
but no index is found, or index is found that does not match upper
inode. In those cases, lookup will not fail and the returned overlay inode
will be hashed by upper inode instead of by lower origin inode.

Fixes: 359f392ca5 ("ovl: lookup index entry for copy up origin")
Cc: <stable@vger.kernel.org> # v4.13
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2017-10-24 16:06:16 +02:00
Christoph Hellwig
942491c9e6 xfs: fix AIM7 regression
Apparently our current rwsem code doesn't like doing the trylock, then
lock for real scheme.  So change our read/write methods to just do the
trylock for the RWF_NOWAIT case.  This fixes a ~25% regression in
AIM7.

Fixes: 91f9943e ("fs: support RWF_NOWAIT for buffered reads")
Reported-by: kernel test robot <xiaolong.ye@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-10-23 18:31:50 -07:00
David S. Miller
f8ddadc4db Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
There were quite a few overlapping sets of changes here.

Daniel's bug fix for off-by-ones in the new BPF branch instructions,
along with the added allowances for "data_end > ptr + x" forms
collided with the metadata additions.

Along with those three changes came veritifer test cases, which in
their final form I tried to group together properly.  If I had just
trimmed GIT's conflict tags as-is, this would have split up the
meta tests unnecessarily.

In the socketmap code, a set of preemption disabling changes
overlapped with the rename of bpf_compute_data_end() to
bpf_compute_data_pointers().

Changes were made to the mv88e6060.c driver set addr method
which got removed in net-next.

The hyperv transport socket layer had a locking change in 'net'
which overlapped with a change of socket state macro usage
in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-22 13:39:14 +01:00
Linus Torvalds
ec0145e9cc Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro:
 "MS_I_VERSION fixes - Mimi's fix + missing bits picked from Matthew
  (his patch contained a duplicate of the fs/namespace.c fix as well,
  but by that point the original fix had already been applied)"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  Convert fs/*/* to SB_I_VERSION
  vfs: fix mounting a filesystem with i_version
2017-10-21 21:39:18 -04:00
Linus Torvalds
03b652e5c0 Merge branch 'fixes-v4.14-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull key handling fixes from James Morris:
 "This includes a fix for the capabilities code from Colin King, and a
  set of further fixes for the keys subsystem. From David:

   - Fix a bunch of places where kernel drivers may access revoked
     user-type keys and don't do it correctly.

   - Fix some ecryptfs bits.

   - Fix big_key to require CONFIG_CRYPTO.

   - Fix a couple of bugs in the asymmetric key type.

   - Fix a race between updating and finding negative keys.

   - Prevent add_key() from updating uninstantiated keys.

   - Make loading of key flags and expiry time atomic when not holding
     locks"

* 'fixes-v4.14-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  commoncap: move assignment of fs_ns to avoid null pointer dereference
  pkcs7: Prevent NULL pointer dereference, since sinfo is not always set.
  KEYS: load key flags and expiry time atomically in proc_keys_show()
  KEYS: Load key expiry time atomically in keyring_search_iterator()
  KEYS: load key flags and expiry time atomically in key_validate()
  KEYS: don't let add_key() update an uninstantiated key
  KEYS: Fix race between updating and finding a negative key
  KEYS: checking the input id parameters before finding asymmetric key
  KEYS: Fix the wrong index when checking the existence of second id
  security/keys: BIG_KEY requires CONFIG_CRYPTO
  ecryptfs: fix dereference of NULL user_key_payload
  fscrypt: fix dereference of NULL user_key_payload
  lib/digsig: fix dereference of NULL user_key_payload
  FS-Cache: fix dereference of NULL user_key_payload
  KEYS: encrypted: fix dereference of NULL user_key_payload
2017-10-20 06:19:38 -04:00
Mathieu Desnoyers
a961e40917 membarrier: Provide register expedited private command
This introduces a "register private expedited" membarrier command which
allows eventual removal of important memory barrier constraints on the
scheduler fast-paths. It changes how the "private expedited" membarrier
command (new to 4.14) is used from user-space.

This new command allows processes to register their intent to use the
private expedited command.  This affects how the expedited private
command introduced in 4.14-rc is meant to be used, and should be merged
before 4.14 final.

Processes are now required to register before using
MEMBARRIER_CMD_PRIVATE_EXPEDITED, otherwise that command returns EPERM.

This fixes a problem that arose when designing requested extensions to
sys_membarrier() to allow JITs to efficiently flush old code from
instruction caches.  Several potential algorithms are much less painful
if the user register intent to use this functionality early on, for
example, before the process spawns the second thread.  Registering at
this time removes the need to interrupt each and every thread in that
process at the first expedited sys_membarrier() system call.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-19 22:13:40 -04:00
Dan Carpenter
0ce5cdc9d7 ovl: Return -ENOMEM if an allocation fails ovl_lookup()
The error code is missing here so it means we return ERR_PTR(0) or NULL.
The other error paths all return an error code so this probably should
as well.

Fixes: 02b69b284c ("ovl: lookup redirects")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2017-10-19 16:19:52 +02:00
Hirofumi Nakagawa
b3885bd6ed ovl: add NULL check in ovl_alloc_inode
This was detected by fault injection test

Signed-off-by: Hirofumi Nakagawa <nklabs@gmail.com>
Fixes: 13cf199d00 ("ovl: allocate an ovl_inode struct")
Cc: <stable@vger.kernel.org> # v4.13
2017-10-19 16:19:51 +02:00
James Morris
494b9ae7ab Merge commit 'tags/keys-fixes-20171018' into fixes-v4.14-rc5 2017-10-19 12:28:38 +11:00
Matthew Garrett
357fdad075 Convert fs/*/* to SB_I_VERSION
[AV: in addition to the fix in previous commit]

Signed-off-by: Matthew Garrett <mjg59@google.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Reviewed-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-10-18 18:51:27 -04:00
Linus Torvalds
73d3393ada Changes since last update:
- fix some more CONFIG_XFS_RT related build problems
 - fix data loss when writeback at eof races eofblocks gc and loses
 - invalidate page cache after fs finishes a dio write
 - remove dirty page state when invalidating pages so releasepage does
   the right thing when handed a dirty page
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Merge tag 'xfs-4.14-fixes-6' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs fixes from Darrick Wong:

 - fix some more CONFIG_XFS_RT related build problems

 - fix data loss when writeback at eof races eofblocks gc and loses

 - invalidate page cache after fs finishes a dio write

 - remove dirty page state when invalidating pages so releasepage does
   the right thing when handed a dirty page

* tag 'xfs-4.14-fixes-6' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: move two more RT specific functions into CONFIG_XFS_RT
  xfs: trim writepage mapping to within eof
  fs: invalidate page cache after end_io() in dio completion
  xfs: cancel dirty pages on invalidation
2017-10-18 14:51:50 -04:00
Linus Torvalds
020b302376 Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
 "Three small fixes:

   - A fix for skd, it was using kfree() to free a structure allocate
     with kmem_cache_alloc().

   - Stable fix for nbd, fixing a regression using the normal ioctl
     based tools.

   - Fix for a previous fix in this series, that fixed up
     inconsistencies between buffered and direct IO"

* 'for-linus' of git://git.kernel.dk/linux-block:
  fs: Avoid invalidation in interrupt context in dio_complete()
  nbd: don't set the device size until we're connected
  skd: Use kmem_cache_free
2017-10-18 14:43:40 -04:00
Long Li
4572f0539c CIFS: SMBD: Fix the definition for SMB2_CHANNEL_RDMA_V1_INVALIDATE
The channel value for requesting server remote invalidating local memory
registration should be 0x00000002

Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2017-10-18 11:52:39 -05:00
Ronnie Sahlberg
7cb3def44c cifs: handle large EA requests more gracefully in smb2+
Update reading the EA using increasingly larger buffer sizes
until the response will fit in the buffer, or we exceed the
(arbitrary) maximum set to 64kb.

Without this change, a user is able to add more and more EAs using
setfattr until the point where the total space of all EAs exceed 2kb
at which point the user can no longer list the EAs at all
and getfattr will abort with an error.

The same issue still exists for EAs in SMB1.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reported-by: Xiaoli Feng <xifeng@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2017-10-18 11:52:39 -05:00
Steve French
06e2290844 Fix encryption labels and lengths for SMB3.1.1
SMB3.1.1 is most secure and recent dialect. Fixup labels and lengths
for sMB3.1.1 signing and encryption.

Signed-off-by: Steve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
2017-10-18 11:52:39 -05:00
David Howells
bc5e3a546d rxrpc: Use MSG_WAITALL to tell sendmsg() to temporarily ignore signals
Make AF_RXRPC accept MSG_WAITALL as a flag to sendmsg() to tell it to
ignore signals whilst loading up the message queue, provided progress is
being made in emptying the queue at the other side.

Progress is defined as the base of the transmit window having being
advanced within 2 RTT periods.  If the period is exceeded with no progress,
sendmsg() will return anyway, indicating how much data has been copied, if
any.

Once the supplied buffer is entirely decanted, the sendmsg() will return.

Signed-off-by: David Howells <dhowells@redhat.com>
2017-10-18 11:43:07 +01:00
David Howells
a68f4a27f5 rxrpc: Support service upgrade from a kernel service
Provide support for a kernel service to make use of the service upgrade
facility.  This involves:

 (1) Pass an upgrade request flag to rxrpc_kernel_begin_call().

 (2) Make rxrpc_kernel_recv_data() return the call's current service ID so
     that the caller can detect service upgrade and see what the service
     was upgraded to.

Signed-off-by: David Howells <dhowells@redhat.com>
2017-10-18 11:37:20 +01:00
Lukas Czerner
ffe51f0142 fs: Avoid invalidation in interrupt context in dio_complete()
Currently we try to defer completion of async DIO to the process context
in case there are any mapped pages associated with the inode so that we
can invalidate the pages when the IO completes. However the check is racy
and the pages can be mapped afterwards. If this happens we might end up
calling invalidate_inode_pages2_range() in dio_complete() in interrupt
context which could sleep. This can be reproduced by generic/451.

Fix this by passing the information whether we can or can't invalidate
to the dio_complete(). Thanks Eryu Guan for reporting this and Jan Kara
for suggesting a fix.

Fixes: 332391a993 ("fs: Fix page cache inconsistency when mixing buffered and AIO DIO")
Reported-by: Eryu Guan <eguan@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Tested-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-17 08:43:09 -06:00
Mimi Zohar
917086ff23 vfs: fix mounting a filesystem with i_version
The mount i_version flag is not enabled in the new sb_flags.  This patch
adds the missing SB_I_VERSION flag.

Fixes: e462ec5 "VFS: Differentiate mount flags (MS_*) from internal
       superblock flags"
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-10-17 02:22:07 -04:00
Arnd Bergmann
785545c898 xfs: move two more RT specific functions into CONFIG_XFS_RT
The last cleanup introduced two harmless warnings:

fs/xfs/xfs_fsmap.c:480:1: warning: '__xfs_getfsmap_rtdev' defined but not used
fs/xfs/xfs_fsmap.c:372:1: warning: 'xfs_getfsmap_rtdev_rtbitmap_helper' defined but not used

This moves those two functions as well.

Fixes: bb9c2e5433 ("xfs: move more RT specific code under CONFIG_XFS_RT")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-10-16 12:26:50 -07:00
Brian Foster
40214d128e xfs: trim writepage mapping to within eof
The writeback rework in commit fbcc025613 ("xfs: Introduce
writeback context for writepages") introduced a subtle change in
behavior with regard to the block mapping used across the
->writepages() sequence. The previous xfs_cluster_write() code would
only flush pages up to EOF at the time of the writepage, thus
ensuring that any pages due to file-extending writes would be
handled on a separate cycle and with a new, updated block mapping.

The updated code establishes a block mapping in xfs_writepage_map()
that could extend beyond EOF if the file has post-eof preallocation.
Because we now use the generic writeback infrastructure and pass the
cached mapping to each writepage call, there is no implicit EOF
limit in place. If eofblocks trimming occurs during ->writepages(),
any post-eof portion of the cached mapping becomes invalid. The
eofblocks code has no means to serialize against writeback because
there are no pages associated with post-eof blocks. Therefore if an
eofblocks trim occurs and is followed by a file-extending buffered
write, not only has the mapping become invalid, but we could end up
writing a page to disk based on the invalid mapping.

Consider the following sequence of events:

- A buffered write creates a delalloc extent and post-eof
  speculative preallocation.
- Writeback starts and on the first writepage cycle, the delalloc
  extent is converted to real blocks (including the post-eof blocks)
  and the mapping is cached.
- The file is closed and xfs_release() trims post-eof blocks. The
  cached writeback mapping is now invalid.
- Another buffered write appends the file with a delalloc extent.
- The concurrent writeback cycle picks up the just written page
  because the writeback range end is LLONG_MAX. xfs_writepage_map()
  attributes it to the (now invalid) cached mapping and writes the
  data to an incorrect location on disk (and where the file offset is
  still backed by a delalloc extent).

This problem is reproduced by xfstests test generic/464, which
triggers racing writes, appends, open/closes and writeback requests.

To address this problem, trim the mapping used during writeback to
within EOF when the mapping is validated. This ensures the mapping
is revalidated for any pages encountered beyond EOF as of the time
the current mapping was cached or last validated.

Reported-by: Eryu Guan <eguan@redhat.com>
Diagnosed-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-10-16 12:26:50 -07:00
Eryu Guan
5e25c269e1 fs: invalidate page cache after end_io() in dio completion
Commit 332391a993 ("fs: Fix page cache inconsistency when mixing
buffered and AIO DIO") moved page cache invalidation from
iomap_dio_rw() to iomap_dio_complete() for iomap based direct write
path, but before the dio->end_io() call, and it re-introdued the bug
fixed by commit c771c14baa ("iomap: invalidate page caches should
be after iomap_dio_complete() in direct write").

I found this because fstests generic/418 started failing on XFS with
v4.14-rc3 kernel, which is the regression test for this specific
bug.

So similarly, fix it by moving dio->end_io() (which does the
unwritten extent conversion) before page cache invalidation, to make
sure next buffer read reads the final real allocations not unwritten
extents. I also add some comments about why should end_io() go first
in case we get it wrong again in the future.

Note that, there's no such problem in the non-iomap based direct
write path, because we didn't remove the page cache invalidation
after the ->direct_IO() in generic_file_direct_write() call, but I
decided to fix dio_complete() too so we don't leave a landmine
there, also be consistent with iomap_dio_complete().

Fixes: 332391a993 ("fs: Fix page cache inconsistency when mixing buffered and AIO DIO")
Signed-off-by: Eryu Guan <eguan@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
2017-10-16 12:11:56 -07:00
Dave Chinner
793d7dbe6d xfs: cancel dirty pages on invalidation
Recently we've had warnings arise from the vm handing us pages
without bufferheads attached to them. This should not ever occur
in XFS, but we don't defend against it properly if it does. The only
place where we remove bufferheads from a page is in
xfs_vm_releasepage(), but we can't tell the difference here between
"page is dirty so don't release" and "page is dirty but is being
invalidated so release it".

In some places that are invalidating pages ask for pages to be
released and follow up afterward calling ->releasepage by checking
whether the page was dirty and then aborting the invalidation. This
is a possible vector for releasing buffers from a page but then
leaving it in the mapping, so we really do need to avoid dirty pages
in xfs_vm_releasepage().

To differentiate between invalidated pages and normal pages, we need
to clear the page dirty flag when invalidating the pages. This can
be done through xfs_vm_invalidatepage(), and will result
xfs_vm_releasepage() seeing the page as clean which matches the
bufferhead state on the page after calling block_invalidatepage().

Hence we can re-add the page dirty check in xfs_vm_releasepage to
catch the case where we might be releasing a page that is actually
dirty and so should not have the bufferheads on it removed. This
will remove one possible vector of "dirty page with no bufferheads"
and so help narrow down the search for the root cause of that
problem.

Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-10-16 12:11:56 -07:00
Eryu Guan
7e86600606 fs/binfmt_misc.c: node could be NULL when evicting inode
inode->i_private is assigned by a Node pointer only after registering a
new binary format, so it could be NULL if inode was created by
bm_fill_super() (or iput() was called by the error path in
bm_register_write()), and this could result in NULL pointer dereference
when evicting such an inode.  e.g.  mount binfmt_misc filesystem then
umount it immediately:

  mount -t binfmt_misc binfmt_misc /proc/sys/fs/binfmt_misc
  umount /proc/sys/fs/binfmt_misc

will result in

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000013
  IP: bm_evict_inode+0x16/0x40 [binfmt_misc]
  ...
  Call Trace:
   evict+0xd3/0x1a0
   iput+0x17d/0x1d0
   dentry_unlink_inode+0xb9/0xf0
   __dentry_kill+0xc7/0x170
   shrink_dentry_list+0x122/0x280
   shrink_dcache_parent+0x39/0x90
   do_one_tree+0x12/0x40
   shrink_dcache_for_umount+0x2d/0x90
   generic_shutdown_super+0x1f/0x120
   kill_litter_super+0x29/0x40
   deactivate_locked_super+0x43/0x70
   deactivate_super+0x45/0x60
   cleanup_mnt+0x3f/0x70
   __cleanup_mnt+0x12/0x20
   task_work_run+0x86/0xa0
   exit_to_usermode_loop+0x6d/0x99
   syscall_return_slowpath+0xba/0xf0
   entry_SYSCALL_64_fastpath+0xa3/0xa

Fix it by making sure Node (e) is not NULL.

Link: http://lkml.kernel.org/r/20171010100642.31786-1-eguan@redhat.com
Fixes: 83f918274e ("exec: binfmt_misc: shift filp_close(interp_file) from kill_node() to bm_evict_inode()")
Signed-off-by: Eryu Guan <eguan@redhat.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-13 16:18:33 -07:00
Matthew Wilcox
f892760aa6 fs/mpage.c: fix mpage_writepage() for pages with buffers
When using FAT on a block device which supports rw_page, we can hit
BUG_ON(!PageLocked(page)) in try_to_free_buffers().  This is because we
call clean_buffers() after unlocking the page we've written.  Introduce
a new clean_page_buffers() which cleans all buffers associated with a
page and call it from within bdev_write_page().

[akpm@linux-foundation.org: s/PAGE_SIZE/~0U/ per Linus and Matthew]
Link: http://lkml.kernel.org/r/20171006211541.GA7409@bombadil.infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Reported-by: Toshi Kani <toshi.kani@hpe.com>
Reported-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Tested-by: Toshi Kani <toshi.kani@hpe.com>
Acked-by: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-13 16:18:33 -07:00
Linus Torvalds
8ff0b97cf2 Changes since last update:
- Fix a stale kernel memory exposure when logging inodes.
 - Fix some build problems with CONFIG_XFS_RT=n
 - Don't change inode mode if the acl write fails, leaving the file totally
   inaccessible.
 - Fix a dangling pointer problem when removing an attr fork under memory
   pressure.
 - Don't crash while trying to invalidate a null buffer associated with a
   corrupt metadata pointer.
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Merge tag 'xfs-4.14-fixes-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs fixes from Darrick Wong:

 - Fix a stale kernel memory exposure when logging inodes.

 - Fix some build problems with CONFIG_XFS_RT=n

 - Don't change inode mode if the acl write fails, leaving the file
   totally inaccessible.

 - Fix a dangling pointer problem when removing an attr fork under
   memory pressure.

 - Don't crash while trying to invalidate a null buffer associated with
   a corrupt metadata pointer.

* tag 'xfs-4.14-fixes-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: handle error if xfs_btree_get_bufs fails
  xfs: reinit btree pointer on attr tree inactivation walk
  xfs: Fix bool initialization/comparison
  xfs: don't change inode mode if ACL update fails
  xfs: move more RT specific code under CONFIG_XFS_RT
  xfs: Don't log uninitialised fields in inode structures
2017-10-12 14:51:13 -07:00
Linus Torvalds
3206e7d5e2 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull quota fix from Jan Kara:
 "A fix for a regression in handling of quota grace times and warnings"

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  quota: Generate warnings for DQUOT_SPACE_NOFAIL allocations
2017-10-12 10:56:06 -07:00
Eric Biggers
f66665c09a ecryptfs: fix dereference of NULL user_key_payload
In eCryptfs, we failed to verify that the authentication token keys are
not revoked before dereferencing their payloads, which is problematic
because the payload of a revoked key is NULL.  request_key() *does* skip
revoked keys, but there is still a window where the key can be revoked
before we acquire the key semaphore.

Fix it by updating ecryptfs_get_key_payload_data() to return
-EKEYREVOKED if the key payload is NULL.  For completeness we check this
for "encrypted" keys as well as "user" keys, although encrypted keys
cannot be revoked currently.

Alternatively we could use key_validate(), but since we'll also need to
fix ecryptfs_get_key_payload_data() to validate the payload length, it
seems appropriate to just check the payload pointer.

Fixes: 237fead619 ("[PATCH] ecryptfs: fs/Makefile and fs/Kconfig")
Reviewed-by: James Morris <james.l.morris@oracle.com>
Cc: <stable@vger.kernel.org>    [v2.6.19+]
Cc: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-10-12 17:16:40 +01:00
Eric Biggers
d60b5b7854 fscrypt: fix dereference of NULL user_key_payload
When an fscrypt-encrypted file is opened, we request the file's master
key from the keyrings service as a logon key, then access its payload.
However, a revoked key has a NULL payload, and we failed to check for
this.  request_key() *does* skip revoked keys, but there is still a
window where the key can be revoked before we acquire its semaphore.

Fix it by checking for a NULL payload, treating it like a key which was
already revoked at the time it was requested.

Fixes: 88bd6ccdcd ("ext4 crypto: add encryption key management facilities")
Reviewed-by: James Morris <james.l.morris@oracle.com>
Cc: <stable@vger.kernel.org>    [v4.1+]
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-10-12 17:16:40 +01:00
Eric Biggers
d124b2c53c FS-Cache: fix dereference of NULL user_key_payload
When the file /proc/fs/fscache/objects (available with
CONFIG_FSCACHE_OBJECT_LIST=y) is opened, we request a user key with
description "fscache:objlist", then access its payload.  However, a
revoked key has a NULL payload, and we failed to check for this.
request_key() *does* skip revoked keys, but there is still a window
where the key can be revoked before we access its payload.

Fix it by checking for a NULL payload, treating it like a key which was
already revoked at the time it was requested.

Fixes: 4fbf4291aa ("FS-Cache: Allow the current state of all objects to be dumped")
Reviewed-by: James Morris <james.l.morris@oracle.com>
Cc: <stable@vger.kernel.org>    [v2.6.32+]
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-10-12 17:16:40 +01:00
Eric Sandeen
93e8befc17 xfs: handle error if xfs_btree_get_bufs fails
Jason reported that a corrupted filesystem failed to replay
the log with a metadata block out of bounds warning:

XFS (dm-2): _xfs_buf_find: Block out of range: block 0x80270fff8, EOFS 0x9c40000

_xfs_buf_find() and xfs_btree_get_bufs() return NULL if
that happens, and then when xfs_alloc_fix_freelist() calls
xfs_trans_binval() on that NULL bp, we oops with:

BUG: unable to handle kernel NULL pointer dereference at 00000000000000f8

We don't handle _xfs_buf_find errors very well, every
caller higher up the stack gets to guess at why it failed.
But we should at least handle it somehow, so return
EFSCORRUPTED here.

Reported-by: Jason L Tibbitts III <tibbs@math.uh.edu>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-10-11 10:21:07 -07:00
Brian Foster
f35c5e10c6 xfs: reinit btree pointer on attr tree inactivation walk
xfs_attr3_root_inactive() walks the attr fork tree to invalidate the
associated blocks. xfs_attr3_node_inactive() recursively descends
from internal blocks to leaf blocks, caching block address values
along the way to revisit parent blocks, locate the next entry and
descend down that branch of the tree.

The code that attempts to reread the parent block is unsafe because
it assumes that the local xfs_da_node_entry pointer remains valid
after an xfs_trans_brelse() and re-read of the parent buffer. Under
heavy memory pressure, it is possible that the buffer has been
reclaimed and reallocated by the time the parent block is reread.
This means that 'btree' can point to an invalid memory address, lead
to a random/garbage value for child_fsb and cause the subsequent
read of the attr fork to go off the rails and return a NULL buffer
for an attr fork offset that is most likely not allocated.

Note that this problem can be manufactured by setting
XFS_ATTR_BTREE_REF to 0 to prevent LRU caching of attr buffers,
creating a file with a multi-level attr fork and removing it to
trigger inactivation.

To address this problem, reinit the node/btree pointers to the
parent buffer after it has been re-read. This ensures btree points
to a valid record and allows the walk to proceed.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-10-11 10:21:07 -07:00