accounting fix and two fixups to appease static checkers.
-----BEGIN PGP SIGNATURE-----
iQFHBAABCAAxFiEEydHwtzie9C7TfviiSn/eOAIR84sFAmG54aMTHGlkcnlvbW92
QGdtYWlsLmNvbQAKCRBKf944AhHzixPBB/4rf0d+oJbBNQQIjTVSO09G9A5pxnU1
CY++W5xppv2hQQX8Czh8iLLYSP3tRh+1xpAlKT+DFsRI3GTh5tXiPf7Mpu76noo3
UAKxiz5NmtqiwrHKZtpsQEJlmwtAFa+qFVJIOiqq1l+gFeiYMueoFEGDgdSCLJrE
P6TL9CZx06Yf+fef7hJnXKR3YM0qras1jV6Adpvu+2g/ciaThzJF3YdyAFYFp7nl
sGnPTXlJ1DDIsiOAgj0oGeQICpjQJOSGNZtxVjhJx5dJjqgKjim0V4MIShqsW/tg
n8LzjrdGh/lR2QfCgOfYmvFrVTeb9QQyF57sT034rGrP6VXlzCkALPi3
=FQag
-----END PGP SIGNATURE-----
Merge tag 'ceph-for-5.16-rc6' of git://github.com/ceph/ceph-client
Pull ceph fixes from Ilya Dryomov:
"An SGID directory handling fix (marked for stable), a metrics
accounting fix and two fixups to appease static checkers"
* tag 'ceph-for-5.16-rc6' of git://github.com/ceph/ceph-client:
ceph: fix up non-directory creation in SGID directories
ceph: initialize pathlen variable in reconnect_caps_cb
ceph: initialize i_size variable in ceph_sync_read
ceph: fix duplicate increment of opened_inodes metric
Commit 054aa8d439 ("fget: check that the fd still exists after getting
a ref to it") fixed a race with getting a reference to a file just as it
was being closed. It was a fairly minimal patch, and I didn't think
re-checking the file pointer lookup would be a measurable overhead,
since it was all right there and cached.
But I was wrong, as pointed out by the kernel test robot.
The 'poll2' case of the will-it-scale.per_thread_ops benchmark regressed
quite noticeably. Admittedly it seems to be a very artificial test:
doing "poll()" system calls on regular files in a very tight loop in
multiple threads.
That means that basically all the time is spent just looking up file
descriptors without ever doing anything useful with them (not that doing
'poll()' on a regular file is useful to begin with). And as a result it
shows the extra "re-check fd" cost as a sore thumb.
Happily, the regression is fixable by just writing the code to loook up
the fd to be better and clearer. There's still a cost to verify the
file pointer, but now it's basically in the noise even for that
benchmark that does nothing else - and the code is more understandable
and has better comments too.
[ Side note: this patch is also a classic case of one that looks very
messy with the default greedy Myers diff - it's much more legible with
either the patience of histogram diff algorithm ]
Link: https://lore.kernel.org/lkml/20211210053743.GA36420@xsang-OptiPlex-9020/
Link: https://lore.kernel.org/lkml/20211213083154.GA20853@linux.intel.com/
Reported-by: kernel test robot <oliver.sang@intel.com>
Tested-by: Carel Si <beibei.si@intel.com>
Cc: Jann Horn <jannh@google.com>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Fix a data corruption vector that can result from the ro remount
process failing to clear all speculative preallocations from files
and the rw remount process not noticing the incomplete cleanup.
-----BEGIN PGP SIGNATURE-----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=N9Wf
-----END PGP SIGNATURE-----
Merge tag 'xfs-5.16-fixes-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs fix from Darrick Wong:
"This fixes a race between a readonly remount process and other
processes that hold a file IOLOCK on files that previously experienced
copy on write, that could result in severe filesystem corruption if
the filesystem is then remounted rw.
I think this is fairly rare (since the only reliable reproducer I have
that fits the second criteria is the experimental xfs_scrub program),
but the race is clear, so we still need to fix this.
Summary:
- Fix a data corruption vector that can result from the ro remount
process failing to clear all speculative preallocations from files
and the rw remount process not noticing the incomplete cleanup"
* tag 'xfs-5.16-fixes-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: remove all COW fork extents when remounting readonly
-----BEGIN PGP SIGNATURE-----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=BUVd
-----END PGP SIGNATURE-----
Merge tag 'io_uring-5.16-2021-12-10' of git://git.kernel.dk/linux-block
Pull io_uring fixes from Jens Axboe:
"A few fixes that are all bound for stable:
- Two syzbot reports for io-wq that turned out to be separate fixes,
but ultimately very closely related
- io_uring task_work running on cancelations"
* tag 'io_uring-5.16-2021-12-10' of git://git.kernel.dk/linux-block:
io-wq: check for wq exit after adding new worker task_work
io_uring: ensure task_work gets run as part of cancelations
io-wq: remove spurious bit clear on task_work addition
-----BEGIN PGP SIGNATURE-----
iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAmGwxl8ACgkQxWXV+ddt
WDvSeQ//T+mv4o7ucldQZCVdN0TTVCkQUhia+ZdMwBcPty2/ZEdap+KEIVmfCV/v
OLRmSNkIPDhHcIc/O3zJ1/AY0DFbb9brYGkMD/qidgPbRArhDZSrDIr+xnrKJ0iq
HFxM01B54l8hJe6GWIGFuuOz+nXUP1o9SfiDOwMDTkqgzz1JSvPec70RKMxG8pTC
4plVrGaUXkKTC8WyBXnSvkP2gvjfJxqnEKv2Ru1eP1t7Bq65aed0+Z32Mogzl2ip
ZSHVlRergeB03xF9YErWSfgofVWLEIXgLCh/Wfq73sMnHUHUGM/dpEKxP911MI00
A5TuTl3I25cVnDv3qMayBPECMCCGZc2vUyXTLCWUNYLb/vEUTI36QBu/KglRURmO
Zx20B+3/7Yu9pFeZ23S+nlNdGDADmjkOfvZIZDoYDzqBAKWM6kZ/9oWiib21Uwi6
ql5oZNl7G6UXLPvgJoq8dqZIj/HYeLEHeqwf/tepSVQLXYzQyWYDMp686z958XI1
K/A/TKaKk19nn1Dhsz4KJeb3xhMFlFN30K7BNjdH3XRH1RrwJP6pLF/WUduJq2qn
rAvJoODLHkby1D9+HqSKW/RToeR5NbBYYdfB0Q8zpy9zF/gZX7wgFc21/4B7qtib
hkKfNSfAVjedOJJWTFCUDnZwwrqtcrKxYzUpdcls/O1AjifK7+U=
=Mh19
-----END PGP SIGNATURE-----
Merge tag 'for-5.16-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"A few more regression fixes and stable patches, mostly one-liners.
Regression fixes:
- fix pointer/ERR_PTR mismatch returned from memdup_user
- reset dedicated zoned mode relocation block group to avoid using it
and filling it without any recourse
Fixes:
- handle a case to FITRIM range (also to make fstests/generic/260
work)
- fix warning when extent buffer state and pages get out of sync
after an IO error
- fix transaction abort when syncing due to missing mapping error set
on metadata inode after inlining a compressed file
- fix transaction abort due to tree-log and zoned mode interacting in
an unexpected way
- fix memory leak of additional extent data when qgroup reservation
fails
- do proper handling of slot search call when deleting root refs"
* tag 'for-5.16-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: replace the BUG_ON in btrfs_del_root_ref with proper error handling
btrfs: zoned: clear data relocation bg on zone finish
btrfs: free exchange changeset on failures
btrfs: fix re-dirty process of tree-log nodes
btrfs: call mapping_set_error() on btree inode with a write error
btrfs: clear extent buffer uptodate when we fail to write it
btrfs: fail if fstrim_range->start == U64_MAX
btrfs: fix error pointer dereference in btrfs_ioctl_rm_dev_v2()
-----BEGIN PGP SIGNATURE-----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=+1L9
-----END PGP SIGNATURE-----
Merge tag '5.16-rc4-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs fixes from Steve French:
"Two cifs/smb3 fixes - one for stable, the other fixes a recently
reported NTLMSSP auth problem"
* tag '5.16-rc4-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
cifs: fix ntlmssp auth when there is no key exchange
cifs: Fix crash on unload of cifs_arc4.ko
has been around for years, but I suspect recent changes may have
widened the race window a little, so I'd like to go ahead and get it in.
-----BEGIN PGP SIGNATURE-----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=GgUu
-----END PGP SIGNATURE-----
Merge tag 'nfsd-5.16-2' of git://linux-nfs.org/~bfields/linux
Pull nfsd fixes from Bruce Fields:
"Fix a race on startup and another in the delegation code.
The latter has been around for years, but I suspect recent changes may
have widened the race window a little, so I'd like to go ahead and get
it in"
* tag 'nfsd-5.16-2' of git://linux-nfs.org/~bfields/linux:
nfsd: fix use-after-free due to delegation race
nfsd: Fix nsfd startup race (again)
- Have tracefs honor the gid mount option
- Have new files in tracefs inherit the parent ownership
- Have direct_ops unregister when it has no more functions
- Properly clean up the ops when unregistering multi direct ops
- Add a sample module to test the multiple direct ops
- Fix memory leak in error path of __create_synth_event()
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCYbOgPBQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qgOtAP0YD+cRLxnRKA376oQVB8zmuZ3mZ/4x
6M1hqruSDlno3AEA19PyHpxl7flFwnBb6Gnfo9VeefcMS5ENDH9p1aHX4wU=
=Tr6t
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"Tracing, ftrace and tracefs fixes:
- Have tracefs honor the gid mount option
- Have new files in tracefs inherit the parent ownership
- Have direct_ops unregister when it has no more functions
- Properly clean up the ops when unregistering multi direct ops
- Add a sample module to test the multiple direct ops
- Fix memory leak in error path of __create_synth_event()"
* tag 'trace-v5.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix possible memory leak in __create_synth_event() error path
ftrace/samples: Add module to test multi direct modify interface
ftrace: Add cleanup to unregister_ftrace_direct_multi
ftrace: Use direct_ops hash in unregister_ftrace_direct
tracefs: Set all files to the same group ownership as the mount option
tracefs: Have new files inherit the ownership of their parent
Fix three bugs in aio poll, and one issue with POLLFREE more broadly:
- aio poll didn't handle POLLFREE, causing a use-after-free.
- aio poll could block while the file is ready.
- aio poll called eventfd_signal() when it isn't allowed.
- POLLFREE didn't handle multiple exclusive waiters correctly.
This has been tested with the libaio test suite, as well as with test
programs I wrote that reproduce the first two bugs. I am sending this
pull request myself as no one seems to be maintaining this code.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQSacvsUNc7UX4ntmEPzXCl4vpKOKwUCYbObthQcZWJpZ2dlcnNA
Z29vZ2xlLmNvbQAKCRDzXCl4vpKOK+3mAQC9W8ApzBleEPI6FXzIIo5AiQT/2jGl
7FbO1MtkdUBU4QEAzf+VWl4Z4BJTgxl44avRdVDpXGAMnbWkd7heY+e3HwA=
=mp+r
-----END PGP SIGNATURE-----
Merge tag 'aio-poll-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux
Pull aio poll fixes from Eric Biggers:
"Fix three bugs in aio poll, and one issue with POLLFREE more broadly:
- aio poll didn't handle POLLFREE, causing a use-after-free.
- aio poll could block while the file is ready.
- aio poll called eventfd_signal() when it isn't allowed.
- POLLFREE didn't handle multiple exclusive waiters correctly.
This has been tested with the libaio test suite, as well as with test
programs I wrote that reproduce the first two bugs. I am sending this
pull request myself as no one seems to be maintaining this code"
* tag 'aio-poll-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux:
aio: Fix incorrect usage of eventfd_signal_allowed()
aio: fix use-after-free due to missing POLLFREE handling
aio: keep poll requests on waitqueue until completed
signalfd: use wake_up_pollfree()
binder: use wake_up_pollfree()
wait: add wake_up_pollfree()
We check IO_WQ_BIT_EXIT before attempting to create a new worker, and
wq exit cancels pending work if we have any. But it's possible to have
a race between the two, where creation checks exit finding it not set,
but we're in the process of exiting. The exit side will cancel pending
creation task_work, but there's a gap where we add task_work after we've
canceled existing creations at exit time.
Fix this by checking the EXIT bit post adding the creation task_work.
If it's set, run the same cancelation that exit does.
Reported-and-tested-by: syzbot+b60c982cb0efc5e05a47@syzkaller.appspotmail.com
Reviewed-by: Hao Xu <haoxu@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If we successfully cancel a work item but that work item needs to be
processed through task_work, then we can be sleeping uninterruptibly
in io_uring_cancel_generic() and never process it. Hence we don't
make forward progress and we end up with an uninterruptible sleep
warning.
While in there, correct a comment that should be IFF, not IIF.
Reported-and-tested-by: syzbot+21e6887c0be14181206d@syzkaller.appspotmail.com
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
A delegation break could arrive as soon as we've called vfs_setlease. A
delegation break runs a callback which immediately (in
nfsd4_cb_recall_prepare) adds the delegation to del_recall_lru. If we
then exit nfs4_set_delegation without hashing the delegation, it will be
freed as soon as the callback is done with it, without ever being
removed from del_recall_lru.
Symptoms show up later as use-after-free or list corruption warnings,
usually in the laundromat thread.
I suspect aba2072f45 "nfsd: grant read delegations to clients holding
writes" made this bug easier to hit, but I looked as far back as v3.0
and it looks to me it already had the same problem. So I'm not sure
where the bug was introduced; it may have been there from the beginning.
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Commit bd5ae9288d ("nfsd: register pernet ops last, unregister first")
has re-opened rpc_pipefs_event() race against nfsd_net_id registration
(register_pernet_subsys()) which has been fixed by commit bb7ffbf29e
("nfsd: fix nsfd startup race triggering BUG_ON").
Restore the order of register_pernet_subsys() vs register_cld_notifier().
Add WARN_ON() to prevent a future regression.
Crash info:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000012
CPU: 8 PID: 345 Comm: mount Not tainted 5.4.144-... #1
pc : rpc_pipefs_event+0x54/0x120 [nfsd]
lr : rpc_pipefs_event+0x48/0x120 [nfsd]
Call trace:
rpc_pipefs_event+0x54/0x120 [nfsd]
blocking_notifier_call_chain
rpc_fill_super
get_tree_keyed
rpc_fs_get_tree
vfs_get_tree
do_mount
ksys_mount
__arm64_sys_mount
el0_svc_handler
el0_svc
Fixes: bd5ae9288d ("nfsd: register pernet ops last, unregister first")
Cc: stable@vger.kernel.org
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We should defer eventfd_signal() to the workqueue when
eventfd_signal_allowed() return false rather than return
true.
Fixes: b542e383d8 ("eventfd: Make signal recursion protection a task bit")
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Link: https://lore.kernel.org/r/20210913111928.98-1-xieyongji@bytedance.com
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
signalfd_poll() and binder_poll() are special in that they use a
waitqueue whose lifetime is the current task, rather than the struct
file as is normally the case. This is okay for blocking polls, since a
blocking poll occurs within one task; however, non-blocking polls
require another solution. This solution is for the queue to be cleared
before it is freed, by sending a POLLFREE notification to all waiters.
Unfortunately, only eventpoll handles POLLFREE. A second type of
non-blocking poll, aio poll, was added in kernel v4.18, and it doesn't
handle POLLFREE. This allows a use-after-free to occur if a signalfd or
binder fd is polled with aio poll, and the waitqueue gets freed.
Fix this by making aio poll handle POLLFREE.
A patch by Ramji Jiyani <ramjiyani@google.com>
(https://lore.kernel.org/r/20211027011834.2497484-1-ramjiyani@google.com)
tried to do this by making aio_poll_wake() always complete the request
inline if POLLFREE is seen. However, that solution had two bugs.
First, it introduced a deadlock, as it unconditionally locked the aio
context while holding the waitqueue lock, which inverts the normal
locking order. Second, it didn't consider that POLLFREE notifications
are missed while the request has been temporarily de-queued.
The second problem was solved by my previous patch. This patch then
properly fixes the use-after-free by handling POLLFREE in a
deadlock-free way. It does this by taking advantage of the fact that
freeing of the waitqueue is RCU-delayed, similar to what eventpoll does.
Fixes: 2c14fa838c ("aio: implement IOCB_CMD_POLL")
Cc: <stable@vger.kernel.org> # v4.18+
Link: https://lore.kernel.org/r/20211209010455.42744-6-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Currently, aio_poll_wake() will always remove the poll request from the
waitqueue. Then, if aio_poll_complete_work() sees that none of the
polled events are ready and the request isn't cancelled, it re-adds the
request to the waitqueue. (This can easily happen when polling a file
that doesn't pass an event mask when waking up its waitqueue.)
This is fundamentally broken for two reasons:
1. If a wakeup occurs between vfs_poll() and the request being
re-added to the waitqueue, it will be missed because the request
wasn't on the waitqueue at the time. Therefore, IOCB_CMD_POLL
might never complete even if the polled file is ready.
2. When the request isn't on the waitqueue, there is no way to be
notified that the waitqueue is being freed (which happens when its
lifetime is shorter than the struct file's). This is supposed to
happen via the waitqueue entries being woken up with POLLFREE.
Therefore, leave the requests on the waitqueue until they are actually
completed (or cancelled). To keep track of when aio_poll_complete_work
needs to be scheduled, use new fields in struct poll_iocb. Remove the
'done' field which is now redundant.
Note that this is consistent with how sys_poll() and eventpoll work;
their wakeup functions do *not* remove the waitqueue entries.
Fixes: 2c14fa838c ("aio: implement IOCB_CMD_POLL")
Cc: <stable@vger.kernel.org> # v4.18+
Link: https://lore.kernel.org/r/20211209010455.42744-5-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
wake_up_poll() uses nr_exclusive=1, so it's not guaranteed to wake up
all exclusive waiters. Yet, POLLFREE *must* wake up all waiters. epoll
and aio poll are fortunately not affected by this, but it's very
fragile. Thus, the new function wake_up_pollfree() has been introduced.
Convert signalfd to use wake_up_pollfree().
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Fixes: d80e731eca ("epoll: introduce POLLFREE to flush ->signalfd_wqh before kfree()")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20211209010455.42744-4-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Warn on the lack of key exchange during NTLMSSP authentication rather
than aborting it as there are some servers that do not set it in
CHALLENGE message.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
I hit the BUG_ON() with generic/475 test case, and to my surprise, all
callers of btrfs_del_root_ref() are already aborting transaction, thus
there is not need for such BUG_ON(), just go to @out label and caller
will properly handle the error.
CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When finishing a zone that is used by a dedicated data relocation
block group, also remove its reference from fs_info, so we're not trying
to use a full block group for allocations during data relocation, which
will always fail.
The result is we're not making any forward progress and end up in a
deadlock situation.
Fixes: c2707a2556 ("btrfs: zoned: add a dedicated data relocation block group")
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Fstests runs on my VMs have show several kmemleak reports like the following.
unreferenced object 0xffff88811ae59080 (size 64):
comm "xfs_io", pid 12124, jiffies 4294987392 (age 6.368s)
hex dump (first 32 bytes):
00 c0 1c 00 00 00 00 00 ff cf 1c 00 00 00 00 00 ................
90 97 e5 1a 81 88 ff ff 90 97 e5 1a 81 88 ff ff ................
backtrace:
[<00000000ac0176d2>] ulist_add_merge+0x60/0x150 [btrfs]
[<0000000076e9f312>] set_state_bits+0x86/0xc0 [btrfs]
[<0000000014fe73d6>] set_extent_bit+0x270/0x690 [btrfs]
[<000000004f675208>] set_record_extent_bits+0x19/0x20 [btrfs]
[<00000000b96137b1>] qgroup_reserve_data+0x274/0x310 [btrfs]
[<0000000057e9dcbb>] btrfs_check_data_free_space+0x5c/0xa0 [btrfs]
[<0000000019c4511d>] btrfs_delalloc_reserve_space+0x1b/0xa0 [btrfs]
[<000000006d37e007>] btrfs_dio_iomap_begin+0x415/0x970 [btrfs]
[<00000000fb8a74b8>] iomap_iter+0x161/0x1e0
[<0000000071dff6ff>] __iomap_dio_rw+0x1df/0x700
[<000000002567ba53>] iomap_dio_rw+0x5/0x20
[<0000000072e555f8>] btrfs_file_write_iter+0x290/0x530 [btrfs]
[<000000005eb3d845>] new_sync_write+0x106/0x180
[<000000003fb505bf>] vfs_write+0x24d/0x2f0
[<000000009bb57d37>] __x64_sys_pwrite64+0x69/0xa0
[<000000003eba3fdf>] do_syscall_64+0x43/0x90
In case brtfs_qgroup_reserve_data() or btrfs_delalloc_reserve_metadata()
fail the allocated extent_changeset will not be freed.
So in btrfs_check_data_free_space() and btrfs_delalloc_reserve_space()
free the allocated extent_changeset to get rid of the allocated memory.
The issue currently only happens in the direct IO write path, but only
after 65b3c08606e5 ("btrfs: fix ENOSPC failure when attempting direct IO
write into NOCOW range"), and also at defrag_one_locked_target(). Every
other place is always calling extent_changeset_free() even if its call
to btrfs_delalloc_reserve_space() or btrfs_check_data_free_space() has
failed.
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There is a report of a transaction abort of -EAGAIN with the following
script.
#!/bin/sh
for d in sda sdb; do
mkfs.btrfs -d single -m single -f /dev/\${d}
done
mount /dev/sda /mnt/test
mount /dev/sdb /mnt/scratch
for dir in test scratch; do
echo 3 >/proc/sys/vm/drop_caches
fio --directory=/mnt/\${dir} --name=fio.\${dir} --rw=read --size=50G --bs=64m \
--numjobs=$(nproc) --time_based --ramp_time=5 --runtime=480 \
--group_reporting |& tee /dev/shm/fio.\${dir}
echo 3 >/proc/sys/vm/drop_caches
done
for d in sda sdb; do
umount /dev/\${d}
done
The stack trace is shown in below.
[3310.967991] BTRFS: error (device sda) in btrfs_commit_transaction:2341: errno=-11 unknown (Error while writing out transaction)
[3310.968060] BTRFS info (device sda): forced readonly
[3310.968064] BTRFS warning (device sda): Skipping commit of aborted transaction.
[3310.968065] ------------[ cut here ]------------
[3310.968066] BTRFS: Transaction aborted (error -11)
[3310.968074] WARNING: CPU: 14 PID: 1684 at fs/btrfs/transaction.c:1946 btrfs_commit_transaction.cold+0x209/0x2c8
[3310.968131] CPU: 14 PID: 1684 Comm: fio Not tainted 5.14.10-300.fc35.x86_64 #1
[3310.968135] Hardware name: DIAWAY Tartu/Tartu, BIOS V2.01.B10 04/08/2021
[3310.968137] RIP: 0010:btrfs_commit_transaction.cold+0x209/0x2c8
[3310.968144] RSP: 0018:ffffb284ce393e10 EFLAGS: 00010282
[3310.968147] RAX: 0000000000000026 RBX: ffff973f147b0f60 RCX: 0000000000000027
[3310.968149] RDX: ffff974ecf098a08 RSI: 0000000000000001 RDI: ffff974ecf098a00
[3310.968150] RBP: ffff973f147b0f08 R08: 0000000000000000 R09: ffffb284ce393c48
[3310.968151] R10: ffffb284ce393c40 R11: ffffffff84f47468 R12: ffff973f101bfc00
[3310.968153] R13: ffff971f20cf2000 R14: 00000000fffffff5 R15: ffff973f147b0e58
[3310.968154] FS: 00007efe65468740(0000) GS:ffff974ecf080000(0000) knlGS:0000000000000000
[3310.968157] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[3310.968158] CR2: 000055691bcbe260 CR3: 000000105cfa4001 CR4: 0000000000770ee0
[3310.968160] PKRU: 55555554
[3310.968161] Call Trace:
[3310.968167] ? dput+0xd4/0x300
[3310.968174] btrfs_sync_file+0x3f1/0x490
[3310.968180] __x64_sys_fsync+0x33/0x60
[3310.968185] do_syscall_64+0x3b/0x90
[3310.968190] entry_SYSCALL_64_after_hwframe+0x44/0xae
[3310.968194] RIP: 0033:0x7efe6557329b
[3310.968200] RSP: 002b:00007ffe0236ebc0 EFLAGS: 00000293 ORIG_RAX: 000000000000004a
[3310.968203] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007efe6557329b
[3310.968204] RDX: 0000000000000000 RSI: 00007efe58d77010 RDI: 0000000000000006
[3310.968205] RBP: 0000000004000000 R08: 0000000000000000 R09: 00007efe58d77010
[3310.968207] R10: 0000000016cacc0c R11: 0000000000000293 R12: 00007efe5ce95980
[3310.968208] R13: 0000000000000000 R14: 00007efe6447c790 R15: 0000000c80000000
[3310.968212] ---[ end trace 1a346f4d3c0d96ba ]---
[3310.968214] BTRFS: error (device sda) in cleanup_transaction:1946: errno=-11 unknown
The abort occurs because of a write hole while writing out freeing tree
nodes of a tree-log tree. For zoned btrfs, we re-dirty a freed tree
node to ensure btrfs can write the region and does not leave a hole on
write on a zoned device. The current code fails to re-dirty a node
when the tree-log tree's depth is greater or equal to 2. That leads to
a transaction abort with -EAGAIN.
Fix the issue by properly re-dirtying a node on walking up the tree.
Fixes: d3575156f6 ("btrfs: zoned: redirty released extent buffers")
CC: stable@vger.kernel.org # 5.12+
Link: https://github.com/kdave/btrfs-progs/issues/415
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
generic/484 fails sometimes with compression on because the write ends
up small enough that it goes into the btree. This means that we never
call mapping_set_error() on the inode itself, because the page gets
marked as fine when we inline it into the metadata. When the metadata
writeback happens we see it and abort the transaction properly and mark
the fs as readonly, however we don't do the mapping_set_error() on
anything. In syncfs() we will simply return 0 if the sb is marked
read-only, so we can't check for this in our syncfs callback. The only
way the error gets returned if we called mapping_set_error() on
something. Fix this by calling mapping_set_error() on the btree inode
mapping. This allows us to properly return an error on syncfs and pass
generic/484 with compression on.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
I got dmesg errors on generic/281 on our overnight fstests. Looking at
the history this happens occasionally, with errors like this
WARNING: CPU: 0 PID: 673217 at fs/btrfs/extent_io.c:6848 assert_eb_page_uptodate+0x3f/0x50
CPU: 0 PID: 673217 Comm: kworker/u4:13 Tainted: G W 5.16.0-rc2+ #469
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014
Workqueue: btrfs-cache btrfs_work_helper
RIP: 0010:assert_eb_page_uptodate+0x3f/0x50
RSP: 0018:ffffae598230bc60 EFLAGS: 00010246
RAX: 0017ffffc0002112 RBX: ffffebaec4100900 RCX: 0000000000001000
RDX: ffffebaec45733c7 RSI: ffffebaec4100900 RDI: ffff9fd98919f340
RBP: 0000000000000d56 R08: ffff9fd98e300000 R09: 0000000000000000
R10: 0001207370a91c50 R11: 0000000000000000 R12: 00000000000007b0
R13: ffff9fd98919f340 R14: 0000000001500000 R15: 0000000001cb0000
FS: 0000000000000000(0000) GS:ffff9fd9fbc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f549fcf8940 CR3: 0000000114908004 CR4: 0000000000370ef0
Call Trace:
extent_buffer_test_bit+0x3f/0x70
free_space_test_bit+0xa6/0xc0
load_free_space_tree+0x1d6/0x430
caching_thread+0x454/0x630
? rcu_read_lock_sched_held+0x12/0x60
? rcu_read_lock_sched_held+0x12/0x60
? rcu_read_lock_sched_held+0x12/0x60
? lock_release+0x1f0/0x2d0
btrfs_work_helper+0xf2/0x3e0
? lock_release+0x1f0/0x2d0
? finish_task_switch.isra.0+0xf9/0x3a0
process_one_work+0x270/0x5a0
worker_thread+0x55/0x3c0
? process_one_work+0x5a0/0x5a0
kthread+0x174/0x1a0
? set_kthread_struct+0x40/0x40
ret_from_fork+0x1f/0x30
This happens because we're trying to read from a extent buffer page that
is !PageUptodate. This happens because we will clear the page uptodate
when we have an IO error, but we don't clear the extent buffer uptodate.
If we do a read later and find this extent buffer we'll think its valid
and not return an error, and then trip over this warning.
Fix this by also clearing uptodate on the extent buffer when this
happens, so that we get an error when we do a btrfs_search_slot() and
find this block later.
CC: stable@vger.kernel.org # 5.4+
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We've always been failing generic/260 because it's testing things we
actually don't care about and thus won't fail for. However we probably
should fail for fstrim_range->start == U64_MAX since we clearly can't
trim anything past that. This in combination with an update to
generic/260 will allow us to pass this test properly.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
If memdup_user() fails the error handing will crash when it tries
to kfree() an error pointer. Just return directly because there is
no cleanup required.
Fixes: 1a15eb724a ("btrfs: use btrfs_get_dev_args_from_path in dev removal ioctls")
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
As people have been asking to allow non-root processes to have access to
the tracefs directory, it was considered best to only allow groups to have
access to the directory, where it is easier to just set the tracefs file
system to a specific group (as other would be too dangerous), and that way
the admins could pick which processes would have access to tracefs.
Unfortunately, this broke tooling on Android that expected the other bit
to be set. For some special cases, for non-root tools to trace the system,
tracefs would be mounted and change the permissions of the top level
directory which gave access to all running tasks permission to the
tracing directory. Even though this would be dangerous to do in a
production environment, for testing environments this can be useful.
Now with the new changes to not allow other (which is still the proper
thing to do), it breaks the testing tooling. Now more code needs to be
loaded on the system to change ownership of the tracing directory.
The real solution is to have tracefs honor the gid=xxx option when
mounting. That is,
(tracing group tracing has value 1003)
mount -t tracefs -o gid=1003 tracefs /sys/kernel/tracing
should have it that all files in the tracing directory should be of the
given group.
Copy the logic from d_walk() from dcache.c and simplify it for the mount
case of tracefs if gid is set. All the files in tracefs will be walked and
their group will be set to the value passed in.
Link: https://lkml.kernel.org/r/20211207171729.2a54e1b3@gandalf.local.home
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-fsdevel@vger.kernel.org
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reported-by: Kalesh Singh <kaleshsingh@google.com>
Reported-by: Yabin Cui <yabinc@google.com>
Fixes: 49d67e4457 ("tracefs: Have tracefs directories not set OTH permission bits by default")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
If directories in tracefs have their ownership changed, then any new files
and directories that are created under those directories should inherit
the ownership of the director they are created in.
Link: https://lkml.kernel.org/r/20211208075720.4855d180@gandalf.local.home
Cc: Kees Cook <keescook@chromium.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Yabin Cui <yabinc@google.com>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: stable@vger.kernel.org
Fixes: 4282d60689 ("tracefs: Add new tracefs file system")
Reported-by: Kalesh Singh <kaleshsingh@google.com>
Reported: https://lore.kernel.org/all/CAC_TJve8MMAv+H_NdLSJXZUSoxOEq2zB_pVaJ9p=7H6Bu3X76g@mail.gmail.com/
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The exit function is wrongly placed in the __init section and this leads
to a crash when the module is unloaded. Just remove both the init and
exit functions since this module does not need them.
Fixes: 71c0286324 ("cifs: fork arc4 and create a separate module...")
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Acked-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Cc: stable@vger.kernel.org # 5.15
Signed-off-by: Steve French <stfrench@microsoft.com>
As part of multiple customer escalations due to file data corruption
after copy on write operations, I wrote some fstests that use fsstress
to hammer on COW to shake things loose. Regrettably, I caught some
filesystem shutdowns due to incorrect rmap operations with the following
loop:
mount <filesystem> # (0)
fsstress <run only readonly ops> & # (1)
while true; do
fsstress <run all ops>
mount -o remount,ro # (2)
fsstress <run only readonly ops>
mount -o remount,rw # (3)
done
When (2) happens, notice that (1) is still running. xfs_remount_ro will
call xfs_blockgc_stop to walk the inode cache to free all the COW
extents, but the blockgc mechanism races with (1)'s reader threads to
take IOLOCKs and loses, which means that it doesn't clean them all out.
Call such a file (A).
When (3) happens, xfs_remount_rw calls xfs_reflink_recover_cow, which
walks the ondisk refcount btree and frees any COW extent that it finds.
This function does not check the inode cache, which means that incore
COW forks of inode (A) is now inconsistent with the ondisk metadata. If
one of those former COW extents are allocated and mapped into another
file (B) and someone triggers a COW to the stale reservation in (A), A's
dirty data will be written into (B) and once that's done, those blocks
will be transferred to (A)'s data fork without bumping the refcount.
The results are catastrophic -- file (B) and the refcount btree are now
corrupt. Solve this race by forcing the xfs_blockgc_free_space to run
synchronously, which causes xfs_icwalk to return to inodes that were
skipped because the blockgc code couldn't take the IOLOCK. This is safe
to do here because the VFS has already prohibited new writer threads.
Fixes: 10ddf64e42 ("xfs: remove leftover CoW reservations when remounting ro")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
The order of these two parameters is just reversed. gcc didn't warn on
that, probably because 'void *' can be converted from or to other
pointer types without warning.
Cc: stable@vger.kernel.org
Fixes: 3d3c950467 ("netfs: Provide readahead and readpage netfs helpers")
Fixes: e1b1240c1f ("netfs: Add write_begin helper")
Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Link: https://lore.kernel.org/r/20211207031449.100510-1-jefflexu@linux.alibaba.com/ # v1
Taking sb_writers whilst holding mmap_lock isn't allowed and will result in
a lockdep warning like that below. The problem comes from cachefiles
needing to take the sb_writers lock in order to do a write to the cache,
but being asked to do this by netfslib called from readpage, readahead or
write_begin[1].
Fix this by always offloading the write to the cache off to a worker
thread. The main thread doesn't need to wait for it, so deadlock can be
avoided.
This can be tested by running the quick xfstests on something like afs or
ceph with lockdep enabled.
WARNING: possible circular locking dependency detected
5.15.0-rc1-build2+ #292 Not tainted
------------------------------------------------------
holetest/65517 is trying to acquire lock:
ffff88810c81d730 (mapping.invalidate_lock#3){.+.+}-{3:3}, at: filemap_fault+0x276/0x7a5
but task is already holding lock:
ffff8881595b53e8 (&mm->mmap_lock#2){++++}-{3:3}, at: do_user_addr_fault+0x28d/0x59c
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&mm->mmap_lock#2){++++}-{3:3}:
validate_chain+0x3c4/0x4a8
__lock_acquire+0x89d/0x949
lock_acquire+0x2dc/0x34b
__might_fault+0x87/0xb1
strncpy_from_user+0x25/0x18c
removexattr+0x7c/0xe5
__do_sys_fremovexattr+0x73/0x96
do_syscall_64+0x67/0x7a
entry_SYSCALL_64_after_hwframe+0x44/0xae
-> #1 (sb_writers#10){.+.+}-{0:0}:
validate_chain+0x3c4/0x4a8
__lock_acquire+0x89d/0x949
lock_acquire+0x2dc/0x34b
cachefiles_write+0x2b3/0x4bb
netfs_rreq_do_write_to_cache+0x3b5/0x432
netfs_readpage+0x2de/0x39d
filemap_read_page+0x51/0x94
filemap_get_pages+0x26f/0x413
filemap_read+0x182/0x427
new_sync_read+0xf0/0x161
vfs_read+0x118/0x16e
ksys_read+0xb8/0x12e
do_syscall_64+0x67/0x7a
entry_SYSCALL_64_after_hwframe+0x44/0xae
-> #0 (mapping.invalidate_lock#3){.+.+}-{3:3}:
check_noncircular+0xe4/0x129
check_prev_add+0x16b/0x3a4
validate_chain+0x3c4/0x4a8
__lock_acquire+0x89d/0x949
lock_acquire+0x2dc/0x34b
down_read+0x40/0x4a
filemap_fault+0x276/0x7a5
__do_fault+0x96/0xbf
do_fault+0x262/0x35a
__handle_mm_fault+0x171/0x1b5
handle_mm_fault+0x12a/0x233
do_user_addr_fault+0x3d2/0x59c
exc_page_fault+0x85/0xa5
asm_exc_page_fault+0x1e/0x30
other info that might help us debug this:
Chain exists of:
mapping.invalidate_lock#3 --> sb_writers#10 --> &mm->mmap_lock#2
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&mm->mmap_lock#2);
lock(sb_writers#10);
lock(&mm->mmap_lock#2);
lock(mapping.invalidate_lock#3);
*** DEADLOCK ***
1 lock held by holetest/65517:
#0: ffff8881595b53e8 (&mm->mmap_lock#2){++++}-{3:3}, at: do_user_addr_fault+0x28d/0x59c
stack backtrace:
CPU: 0 PID: 65517 Comm: holetest Not tainted 5.15.0-rc1-build2+ #292
Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014
Call Trace:
dump_stack_lvl+0x45/0x59
check_noncircular+0xe4/0x129
? print_circular_bug+0x207/0x207
? validate_chain+0x461/0x4a8
? add_chain_block+0x88/0xd9
? hlist_add_head_rcu+0x49/0x53
check_prev_add+0x16b/0x3a4
validate_chain+0x3c4/0x4a8
? check_prev_add+0x3a4/0x3a4
? mark_lock+0xa5/0x1c6
__lock_acquire+0x89d/0x949
lock_acquire+0x2dc/0x34b
? filemap_fault+0x276/0x7a5
? rcu_read_unlock+0x59/0x59
? add_to_page_cache_lru+0x13c/0x13c
? lock_is_held_type+0x7b/0xd3
down_read+0x40/0x4a
? filemap_fault+0x276/0x7a5
filemap_fault+0x276/0x7a5
? pagecache_get_page+0x2dd/0x2dd
? __lock_acquire+0x8bc/0x949
? pte_offset_kernel.isra.0+0x6d/0xc3
__do_fault+0x96/0xbf
? do_fault+0x124/0x35a
do_fault+0x262/0x35a
? handle_pte_fault+0x1c1/0x20d
__handle_mm_fault+0x171/0x1b5
? handle_pte_fault+0x20d/0x20d
? __lock_release+0x151/0x254
? mark_held_locks+0x1f/0x78
? rcu_read_unlock+0x3a/0x59
handle_mm_fault+0x12a/0x233
do_user_addr_fault+0x3d2/0x59c
? pgtable_bad+0x70/0x70
? rcu_read_lock_bh_held+0xab/0xab
exc_page_fault+0x85/0xa5
? asm_exc_page_fault+0x8/0x30
asm_exc_page_fault+0x1e/0x30
RIP: 0033:0x40192f
Code: ff 48 89 c3 48 8b 05 50 28 00 00 48 85 ed 7e 23 31 d2 4b 8d 0c 2f eb 0a 0f 1f 00 48 8b 05 39 28 00 00 48 0f af c2 48 83 c2 01 <48> 89 1c 01 48 39 d5 7f e8 8b 0d f2 27 00 00 31 c0 85 c9 74 0e 8b
RSP: 002b:00007f9931867eb0 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 00007f9931868700 RCX: 00007f993206ac00
RDX: 0000000000000001 RSI: 0000000000000000 RDI: 00007ffc13e06ee0
RBP: 0000000000000100 R08: 0000000000000000 R09: 00007f9931868700
R10: 00007f99318689d0 R11: 0000000000000202 R12: 00007ffc13e06ee0
R13: 0000000000000c00 R14: 00007ffc13e06e00 R15: 00007f993206a000
Fixes: 726218fdc2 ("netfs: Define an interface to talk to a cache")
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Jeff Layton <jlayton@kernel.org>
cc: Jan Kara <jack@suse.cz>
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/20210922110420.GA21576@quack2.suse.cz/ [1]
Link: https://lore.kernel.org/r/163887597541.1596626.2668163316598972956.stgit@warthog.procyon.org.uk/ # v1
There's a small race here where the task_work could finish and drop
the worker itself, so that by the time that task_work_add() returns
with a successful addition we've already put the worker.
The worker callbacks clear this bit themselves, so we don't actually
need to manually clear it in the caller. Get rid of it.
Reported-by: syzbot+b60c982cb0efc5e05a47@syzkaller.appspotmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-----BEGIN PGP SIGNATURE-----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=hChf
-----END PGP SIGNATURE-----
Merge tag '5.16-rc3-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs fixes from Steve French:
"Three SMB3 multichannel/fscache fixes and a DFS fix.
In testing multichannel reconnect scenarios recently various problems
with the cifs.ko implementation of fscache were found (e.g. incorrect
initialization of fscache cookies in some cases)"
* tag '5.16-rc3-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
cifs: avoid use of dstaddr as key for fscache client cookie
cifs: add server conn_id to fscache client cookie
cifs: wait for tcon resource_id before getting fscache super
cifs: fix missed refcounting of ipc tcon
-----BEGIN PGP SIGNATURE-----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=Xy6S
-----END PGP SIGNATURE-----
Merge tag 'io_uring-5.16-2021-12-03' of git://git.kernel.dk/linux-block
Pull io_uring fix from Jens Axboe:
"Just a single fix preventing repeated retries of task_work based io-wq
thread creation, fixing a regression from when io-wq was made more (a
bit too much) resilient against signals"
* tag 'io_uring-5.16-2021-12-03' of git://git.kernel.dk/linux-block:
io-wq: don't retry task_work creation failure on fatal conditions
* Since commit 486408d690 ("gfs2: Cancel remote delete work
asynchronously"), inode create and lookup-by-number can overlap more
easily and we can end up with temporary duplicate inodes. Fix the
code to prevent that.
* Fix a BUG demoting weak glock holders from a remote node.
-----BEGIN PGP SIGNATURE-----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=7HvB
-----END PGP SIGNATURE-----
Merge tag 'gfs2-v5.16-rc4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2
Pull gfs2 fixes from Andreas Gruenbacher:
- Since commit 486408d690 ("gfs2: Cancel remote delete work
asynchronously"), inode create and lookup-by-number can overlap more
easily and we can end up with temporary duplicate inodes. Fix the
code to prevent that.
- Fix a BUG demoting weak glock holders from a remote node.
* tag 'gfs2-v5.16-rc4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
gfs2: gfs2_create_inode rework
gfs2: gfs2_inode_lookup rework
gfs2: gfs2_inode_lookup cleanup
gfs2: Fix remote demote of weak glock holders
server->dstaddr can change when the DNS mapping for the
server hostname changes. But conn_id is a u64 counter
that is incremented each time a new TCP connection
is setup. So use only that as a key.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
The fscache client cookie uses the server address
(and port) as the cookie key. This is a problem when
nosharesock is used. Two different connections will
use duplicate cookies. Avoid this by adding
server->conn_id to the key, so that it's guaranteed
that cookie will not be duplicated.
Also, for secondary channels of a session, copy the
fscache pointer from the primary channel. The primary
channel is guaranteed not to go away as long as secondary
channels are in use. Also addresses minor problem found
by kernel test robot.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
The logic for initializing tcon->resource_id is done inside
cifs_root_iget. fscache super cookie relies on this for aux
data. So we need to push the fscache initialization to this
later point during mount.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Fix missed refcounting of IPC tcon used for getting domain-based DFS
root referrals. We want to keep it alive as long as mount is active
and can be refreshed. For standalone DFS root referrals it wouldn't
be a problem as the client ends up having an IPC tcon for both mount
and cache.
Fixes: c88f7dcd6d ("cifs: support nested dfs links over reconnect")
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
Jann Horn points out that there is another possible race wrt Unix domain
socket garbage collection, somewhat reminiscent of the one fixed in
commit cbcf01128d ("af_unix: fix garbage collect vs MSG_PEEK").
See the extended comment about the garbage collection requirements added
to unix_peek_fds() by that commit for details.
The race comes from how we can locklessly look up a file descriptor just
as it is in the process of being closed, and with the right artificial
timing (Jann added a few strategic 'mdelay(500)' calls to do that), the
Unix domain socket garbage collector could see the reference count
decrement of the close() happen before fget() took its reference to the
file and the file was attached onto a new file descriptor.
This is all (intentionally) correct on the 'struct file *' side, with
RCU lookups and lockless reference counting very much part of the
design. Getting that reference count out of order isn't a problem per
se.
But the garbage collector can get confused by seeing this situation of
having seen a file not having any remaining external references and then
seeing it being attached to an fd.
In commit cbcf01128d ("af_unix: fix garbage collect vs MSG_PEEK") the
fix was to serialize the file descriptor install with the garbage
collector by taking and releasing the unix_gc_lock.
That's not really an option here, but since this all happens when we are
in the process of looking up a file descriptor, we can instead simply
just re-check that the file hasn't been closed in the meantime, and just
re-do the lookup if we raced with a concurrent close() of the same file
descriptor.
Reported-and-tested-by: Jann Horn <jannh@google.com>
Acked-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We don't want to be retrying task_work creation failure if there's
an actual signal pending for the parent task. If we do, then we can
enter an infinite loop of perpetually retrying and each retry failing
with -ERESTARTNOINTR because a signal is pending.
Fixes: 3146cba99a ("io-wq: make worker creation resilient against signals")
Reported-by: Florian Fischer <florian.fl.fischer@fau.de>
Link: https://lore.kernel.org/io-uring/20211202165606.mqryio4yzubl7ms5@pasture/
Tested-by: Florian Fischer <florian.fl.fischer@fau.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When gfs2_lookup_by_inum() calls gfs2_inode_lookup() for an uncached
inode, gfs2_inode_lookup() will place a new tentative inode into the
inode cache before verifying that there is a valid inode at the given
address. This can race with gfs2_create_inode() which doesn't check for
duplicates inodes. gfs2_create_inode() will try to assign the new inode
to the corresponding inode glock, and glock_set_object() will complain
that the glock is still in use by gfs2_inode_lookup's tentative inode.
We noticed this bug after adding commit 486408d690 ("gfs2: Cancel
remote delete work asynchronously") which allowed delete_work_func() to
race with gfs2_create_inode(), but the same race exists for
open-by-handle.
Fix that by switching from insert_inode_hash() to
insert_inode_locked4(), which does check for duplicate inodes. We know
we've just managed to to allocate the new inode, so an inode tentatively
created by gfs2_inode_lookup() will eventually go away and
insert_inode_locked4() will always succeed.
In addition, don't flush the inode glock work anymore (this can now only
make things worse) and clean up glock_{set,clear}_object for the inode
glock somewhat.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Rework gfs2_inode_lookup() to only set up the new inode's glocks after
verifying that the new inode is valid.
There is no need for flushing the inode glock work queue anymore now,
so remove that as well.
While at it, get rid of the useless wrapper around iget5_locked() and
its unnecessary is_bad_inode() check.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
In gfs2_inode_lookup, once the inode has been looked up, we check if the
inode generation (no_formal_ino) is the one we're looking for. If it
isn't and the inode wasn't in the inode cache, we discard the newly
looked up inode. This is unnecessary, complicates the code, and makes
future changes to gfs2_inode_lookup harder, so change the code to retain
newly looked up inodes instead.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
When we mock up a temporary holder in gfs2_glock_cb to demote weak holders in
response to a remote locking conflict, we don't set the HIF_HOLDER flag. This
causes function may_grant to BUG. Fix by setting the missing HIF_HOLDER flag
in the mock glock holder.
In addition, define the mock glock holder where it is used.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
