When the first file is opened, ext4 samples the mountpoint of the
filesystem in 64 bytes of the super block. It does so using
strlcpy(), this means that the remaining bytes in the super block
string buffer are untouched. If the mount point before had a longer
path than the current one, it can be reconstructed.
Consider the case where the fs was mounted to "/media/johnjdeveloper"
and later to "/". The super block buffer then contains
"/\x00edia/johnjdeveloper".
This case was seen in the wild and caused confusion how the name
of a developer ands up on the super block of a filesystem used
in production...
Fix this by using strncpy() instead of strlcpy(). The superblock
field is defined to be a fixed-size char array, and it is already
marked using __nonstring in fs/ext4/ext4.h. The consumer of the field
in e2fsprogs already assumes that in the case of a 64+ byte mount
path, that s_last_mounted will not be NUL terminated.
Link: https://lore.kernel.org/r/X9ujIOJG/HqMr88R@mit.edu
Reported-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
The wrapper is now useless since it does what
ext4_handle_dirty_metadata() does. Just remove it.
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20201216101844.22917-9-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
When setting password salt in the superblock, we forget to recompute the
superblock checksum so it will not match until the next superblock
modification which recomputes the checksum. Fix it.
CC: Michael Halcrow <mhalcrow@google.com>
Reported-by: Andreas Dilger <adilger@dilger.ca>
Fixes: 9bd8212f98 ("ext4 crypto: add encryption policy and password salt support")
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20201216101844.22917-8-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
If journalling is still working at the moment we get to writing error
information to the superblock we cannot write directly to the superblock
as such write could race with journalled update of the superblock and
cause journal checksum failures, writing inconsistent information to the
journal or other problems. We cannot journal the superblock directly
from the error handling functions as we are running in uncertain context
and could deadlock so just punt journalled superblock update to a
workqueue.
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20201216101844.22917-5-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Protect all superblock modifications (including checksum computation)
with a superblock buffer lock. That way we are sure computed checksum
matches current superblock contents (a mismatch could cause checksum
failures in nojournal mode or if an unjournalled superblock update races
with a journalled one). Also we avoid modifying superblock contents
while it is being written out (which can cause DIF/DIX failures if we
are running in nojournal mode).
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20201216101844.22917-4-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Everybody passes 1 as sync argument of ext4_commit_super(). Just drop
it.
Reviewed-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20201216101844.22917-3-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
ext4_bio_write_page does not need wbc parameter, since its parameter
io contains the io_wbc field. The io::io_wbc is initialized by
ext4_io_submit_init which is called in ext4_writepages and
ext4_writepage functions prior to ext4_bio_write_page.
Therefor, when ext4_bio_write_page is called, wbc info
has already been included in io parameter.
Signed-off-by: Lei Chen <lennychen@tencent.com>
Link: https://lore.kernel.org/r/1607669664-25656-1-git-send-email-lennychen@tencent.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
save_error_info() is always called together with ext4_handle_error().
Combine them into a single call and move unconditional bits out of
save_error_info() into ext4_handle_error().
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20201216101844.22917-2-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Commit cfd7323772 ("ext4: add prefetching for block allocation
bitmaps") introduced block bitmap prefetch, and expects to read block
bitmaps of flex_bg through an IO. However, it seems to ignore the
value range of s_log_groups_per_flex. In the scenario where the value
of s_log_groups_per_flex is greater than 27, s_mb_prefetch or
s_mb_prefetch_limit will overflow, cause a divide zero exception.
In addition, the logic of calculating nr is also flawed, because the
size of flexbg is fixed during a single mount, but s_mb_prefetch can
be modified, which causes nr to fail to meet the value condition of
[1, flexbg_size].
To solve this problem, we need to set the upper limit of
s_mb_prefetch. Since we expect to load block bitmaps of a flex_bg
through an IO, we can consider determining a reasonable upper limit
among the IO limit parameters. After consideration, we chose
BLK_MAX_SEGMENT_SIZE. This is a good choice to solve divide zero
problem and avoiding performance degradation.
[ Some minor code simplifications to make the changes easy to follow -- TYT ]
Reported-by: Tosk Robot <tencent_os_robot@tencent.com>
Signed-off-by: Chunguang Xu <brookxu@tencent.com>
Reviewed-by: Samuel Liao <samuelliao@tencent.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://lore.kernel.org/r/1607051143-24508-1-git-send-email-brookxu@tencent.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
When filesystem inconsistency is detected with group locked, we
currently try to modify superblock to store error there without
blocking. However this can cause superblock checksum failures (or
DIF/DIX failure) when the superblock is just being written out.
Make error handling code just store error information in ext4_sb_info
structure and copy it to on-disk superblock only in ext4_commit_super().
In case of error happening with group locked, we just postpone the
superblock flushing to a workqueue.
[ Added fixup so that s_first_error_* does not get updated after
the file system is remounted.
Also added fix for syzbot failure. - Ted ]
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20201127113405.26867-8-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Hillf Danton <hdanton@sina.com>
Reported-by: syzbot+9043030c040ce1849a60@syzkaller.appspotmail.com
Update copyrights for files that have gotten some major rewrites lately.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There is no point in duplicating the file name in the top of the file
comment.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
this is one of the cases where we need to use d_real() - we are
using more than the name of dentry here. ->d_sb is used as well,
so in case of hostfs being used as a layer we get the wrong
superblock.
Reported-by: Johannes Berg <johannes@sipsolutions.net>
Tested-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
- fix long-standing limitation on open-unlink-fop pattern
- add refcount to p9_fid (fixes the above and will allow for more
cleanups and simplifications in the future)
-----BEGIN PGP SIGNATURE-----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=DKlc
-----END PGP SIGNATURE-----
Merge tag '9p-for-5.11-rc1' of git://github.com/martinetd/linux
Pull 9p update from Dominique Martinet:
- fix long-standing limitation on open-unlink-fop pattern
- add refcount to p9_fid (fixes the above and will allow for more
cleanups and simplifications in the future)
* tag '9p-for-5.11-rc1' of git://github.com/martinetd/linux:
9p: Remove unnecessary IS_ERR() check
9p: Uninitialized variable in v9fs_writeback_fid()
9p: Fix writeback fid incorrectly being attached to dentry
9p: apply review requests for fid refcounting
9p: add refcount to p9_fid struct
fs/9p: search open fids first
fs/9p: track open fids
fs/9p: fix create-unlink-getattr idiom
-----BEGIN PGP SIGNATURE-----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=1sd/
-----END PGP SIGNATURE-----
Merge tag '5.11-rc-smb3-part2' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs fixes from Steve French:
"Four small CIFS/SMB3 fixes (witness protocol and reconnect related),
and two that add ability to get and set auditing information in the
security descriptor (SACL), which can be helpful not just for backup
scenarios ("smbinfo secdesc" etc.) but also for improving security"
* tag '5.11-rc-smb3-part2' of git://git.samba.org/sfrench/cifs-2.6:
Add SMB 2 support for getting and setting SACLs
SMB3: Add support for getting and setting SACLs
cifs: Avoid error pointer dereference
cifs: Re-indent cifs_swn_reconnect()
cifs: Unlock on errors in cifs_swn_reconnect()
cifs: Delete a stray unlock in cifs_swn_reconnect()
* PSCI relay at EL2 when "protected KVM" is enabled
* New exception injection code
* Simplification of AArch32 system register handling
* Fix PMU accesses when no PMU is enabled
* Expose CSV3 on non-Meltdown hosts
* Cache hierarchy discovery fixes
* PV steal-time cleanups
* Allow function pointers at EL2
* Various host EL2 entry cleanups
* Simplification of the EL2 vector allocation
s390:
* memcg accouting for s390 specific parts of kvm and gmap
* selftest for diag318
* new kvm_stat for when async_pf falls back to sync
x86:
* Tracepoints for the new pagetable code from 5.10
* Catch VFIO and KVM irqfd events before userspace
* Reporting dirty pages to userspace with a ring buffer
* SEV-ES host support
* Nested VMX support for wait-for-SIPI activity state
* New feature flag (AVX512 FP16)
* New system ioctl to report Hyper-V-compatible paravirtualization features
Generic:
* Selftest improvements
-----BEGIN PGP SIGNATURE-----
iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAl/bdL4UHHBib256aW5p
QHJlZGhhdC5jb20ACgkQv/vSX3jHroNgQQgAnTH6rhXa++Zd5F0EM2NwXwz3iEGb
lOq1DZSGjs6Eekjn8AnrWbmVQr+CBCuGU9MrxpSSzNDK/awryo3NwepOWAZw9eqk
BBCVwGBbJQx5YrdgkGC0pDq2sNzcpW/VVB3vFsmOxd9eHblnuKSIxEsCCXTtyqIt
XrLpQ1UhvI4yu102fDNhuFw2EfpzXm+K0Lc0x6idSkdM/p7SyeOxiv8hD4aMr6+G
bGUQuMl4edKZFOWFigzr8NovQAvDHZGrwfihu2cLRYKLhV97QuWVmafv/yYfXcz2
drr+wQCDNzDOXyANnssmviazrhOX0QmTAhbIXGGX/kTxYKcfPi83ZLoI3A==
=ISud
-----END PGP SIGNATURE-----
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini:
"Much x86 work was pushed out to 5.12, but ARM more than made up for it.
ARM:
- PSCI relay at EL2 when "protected KVM" is enabled
- New exception injection code
- Simplification of AArch32 system register handling
- Fix PMU accesses when no PMU is enabled
- Expose CSV3 on non-Meltdown hosts
- Cache hierarchy discovery fixes
- PV steal-time cleanups
- Allow function pointers at EL2
- Various host EL2 entry cleanups
- Simplification of the EL2 vector allocation
s390:
- memcg accouting for s390 specific parts of kvm and gmap
- selftest for diag318
- new kvm_stat for when async_pf falls back to sync
x86:
- Tracepoints for the new pagetable code from 5.10
- Catch VFIO and KVM irqfd events before userspace
- Reporting dirty pages to userspace with a ring buffer
- SEV-ES host support
- Nested VMX support for wait-for-SIPI activity state
- New feature flag (AVX512 FP16)
- New system ioctl to report Hyper-V-compatible paravirtualization features
Generic:
- Selftest improvements"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (171 commits)
KVM: SVM: fix 32-bit compilation
KVM: SVM: Add AP_JUMP_TABLE support in prep for AP booting
KVM: SVM: Provide support to launch and run an SEV-ES guest
KVM: SVM: Provide an updated VMRUN invocation for SEV-ES guests
KVM: SVM: Provide support for SEV-ES vCPU loading
KVM: SVM: Provide support for SEV-ES vCPU creation/loading
KVM: SVM: Update ASID allocation to support SEV-ES guests
KVM: SVM: Set the encryption mask for the SVM host save area
KVM: SVM: Add NMI support for an SEV-ES guest
KVM: SVM: Guest FPU state save/restore not needed for SEV-ES guest
KVM: SVM: Do not report support for SMM for an SEV-ES guest
KVM: x86: Update __get_sregs() / __set_sregs() to support SEV-ES
KVM: SVM: Add support for CR8 write traps for an SEV-ES guest
KVM: SVM: Add support for CR4 write traps for an SEV-ES guest
KVM: SVM: Add support for CR0 write traps for an SEV-ES guest
KVM: SVM: Add support for EFER write traps for an SEV-ES guest
KVM: SVM: Support string IO operations for an SEV-ES guest
KVM: SVM: Support MMIO for an SEV-ES guest
KVM: SVM: Create trace events for VMGEXIT MSR protocol processing
KVM: SVM: Create trace events for VMGEXIT processing
...
Get rid of TASK_UNINTERRUPTIBLE and waiting with finish_wait before
going for next iteration in __io_uring_task_cancel(), because
__io_uring_files_cancel() doesn't expect that sheduling is disallowed.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Might happen that __io_uring_cancel_task_requests() cancels nothing but
there are task_works pending. We need to always run them.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
* Don't wait for unfreeze of the wrong filesystems.
* Remove an obsolete delete_work_func hack and an incorrect sb_start_write.
* Minor documentation updates and cosmetic care.
-----BEGIN PGP SIGNATURE-----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=jt08
-----END PGP SIGNATURE-----
Merge tag 'gfs2-for-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2
Pull gfs2 updates from Andreas Gruenbacher:
- Don't wait for unfreeze of the wrong filesystems
- Remove an obsolete delete_work_func hack and an incorrect
sb_start_write
- Minor documentation updates and cosmetic care
* tag 'gfs2-for-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
gfs2: in signal_our_withdraw wait for unfreeze of _this_ fs only
gfs2: Remove sb_start_write from gfs2_statfs_sync
gfs2: remove trailing semicolons from macro definitions
Revert "GFS2: Prevent delete work from occurring on glocks used for create"
gfs2: Make inode operations static
MAINTAINERS: Add gfs2 bug tracker link
Documentation: Update filesystems/gfs2.rst
io_uring no longer issues full cancelations on the io-wq, so remove any
remnants of this code and the IO_WQ_BIT_CANCEL flag.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Before IORING_SETUP_ATTACH_WQ, we could just cancel everything on the
io-wq when exiting. But that's not the case if they are shared, so
cancel for the specific ctx instead.
Cc: stable@vger.kernel.org
Fixes: 24369c2e3b ("io_uring: add io-wq workqueue sharing")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCX94a9QAKCRCRxhvAZXjc
ovWlAQCazbbYOeb2hHwBq8iMX+jS2ZDyOXIQgZvQtR1e8UOChwD7BNIZnAzCMbCq
kONk43x+aIrIRknKnY5oT8w7fD4h9QQ=
=c1y6
-----END PGP SIGNATURE-----
Merge tag 'close-range-cloexec-unshare-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull close_range fix from Christian Brauner:
"syzbot reported a bug when asking close_range() to unshare the file
descriptor table and making all fds close-on-exec.
If CLOSE_RANGE_UNSHARE the caller will receive a private file
descriptor table in case their file descriptor table is currently
shared before operating on the requested file descriptor range.
For the case where the caller has requested all file descriptors to be
actually closed via e.g. close_range(3, ~0U, CLOSE_RANGE_UNSHARE) the
kernel knows that the caller does not need any of the file descriptors
anymore and will optimize the close operation by only copying all
files in the range from 0 to 3 and no others.
However, if the caller requested CLOSE_RANGE_CLOEXEC together with
CLOSE_RANGE_UNSHARE the caller wants to still make use of the file
descriptors so the kernel needs to copy all of them and can't
optimize.
The original patch didn't account for this and thus could cause oopses
as evidenced by the syzbot report because it assumed that all fds had
been copied. Fix this by handling the CLOSE_RANGE_CLOEXEC case and
copying all fds if the two flags are specified together.
This should've been caught in the selftests but the original patch
didn't cover this case and I didn't catch it during review. So in
addition to the bugfix I'm also adding selftests. They will reliably
reproduce the bug on a non-fixed kernel and allows us to catch
regressions and verify correct behavior.
Note, the kernel selftest tree contained a bunch of changes that made
the original selftest fail to compile so there are small fixups in
here make them compile without warnings"
* tag 'close-range-cloexec-unshare-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
selftests/core: add regression test for CLOSE_RANGE_UNSHARE | CLOSE_RANGE_CLOEXEC
selftests/core: add test for CLOSE_RANGE_UNSHARE | CLOSE_RANGE_CLOEXEC
selftests/core: handle missing syscall number for close_range
selftests/core: fix close_range_test build after XFAIL removal
close_range: unshare all fds for CLOSE_RANGE_UNSHARE | CLOSE_RANGE_CLOEXEC
Merge still more updates from Andrew Morton:
"18 patches.
Subsystems affected by this patch series: mm (memcg and cleanups) and
epoll"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm/Kconfig: fix spelling mistake "whats" -> "what's"
selftests/filesystems: expand epoll with epoll_pwait2
epoll: wire up syscall epoll_pwait2
epoll: add syscall epoll_pwait2
epoll: convert internal api to timespec64
epoll: eliminate unnecessary lock for zero timeout
epoll: replace gotos with a proper loop
epoll: pull all code between fetch_events and send_event into the loop
epoll: simplify and optimize busy loop logic
epoll: move eavail next to the list_empty_careful check
epoll: pull fatal signal checks into ep_send_events()
epoll: simplify signal handling
epoll: check for events when removing a timed out thread from the wait queue
mm/memcontrol:rewrite mem_cgroup_page_lruvec()
mm, kvm: account kvm_vcpu_mmap to kmemcg
mm/memcg: remove unused definitions
mm/memcg: warning on !memcg after readahead page charged
mm/memcg: bail early from swap accounting if memcg disabled
Add syscall epoll_pwait2, an epoll_wait variant with nsec resolution that
replaces int timeout with struct timespec. It is equivalent otherwise.
int epoll_pwait2(int fd, struct epoll_event *events,
int maxevents,
const struct timespec *timeout,
const sigset_t *sigset);
The underlying hrtimer is already programmed with nsec resolution.
pselect and ppoll also set nsec resolution timeout with timespec.
The sigset_t in epoll_pwait has a compat variant. epoll_pwait2 needs
the same.
For timespec, only support this new interface on 2038 aware platforms
that define __kernel_timespec_t. So no CONFIG_COMPAT_32BIT_TIME.
Link: https://lkml.kernel.org/r/20201121144401.3727659-3-willemdebruijn.kernel@gmail.com
Signed-off-by: Willem de Bruijn <willemb@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "add epoll_pwait2 syscall", v4.
Enable nanosecond timeouts for epoll.
Analogous to pselect and ppoll, introduce an epoll_wait syscall
variant that takes a struct timespec instead of int timeout.
This patch (of 4):
Make epoll more consistent with select/poll: pass along the timeout as
timespec64 pointer.
In anticipation of additional changes affecting all three polling
mechanisms:
- add epoll_pwait2 syscall with timespec semantics,
and share poll_select_set_timeout implementation.
- compute slack before conversion to absolute time,
to save one ktime_get_ts64 call.
Link: https://lkml.kernel.org/r/20201121144401.3727659-1-willemdebruijn.kernel@gmail.com
Link: https://lkml.kernel.org/r/20201121144401.3727659-2-willemdebruijn.kernel@gmail.com
Signed-off-by: Willem de Bruijn <willemb@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We call ep_events_available() under lock when timeout is 0, and then call
it without locks in the loop for the other cases.
Instead, call ep_events_available() without lock for all cases. For
non-zero timeouts, we will recheck after adding the thread to the wait
queue. For zero timeout cases, by definition, user is opportunistically
polling and will have to call epoll_wait again in the future.
Note that this lock was kept in c5a282e963 because the whole loop was
historically under lock.
This patch results in a 1% CPU/RPC reduction in RPC benchmarks.
Link: https://lkml.kernel.org/r/20201106231635.3528496-9-soheil.kdev@gmail.com
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Khazhismel Kumykov <khazhy@google.com>
Cc: Guantao Liu <guantaol@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The existing loop is pointless, and the labels make it really hard to
follow the structure.
Replace that control structure with a simple loop that returns when there
are new events, there is a signal, or the thread has timed out.
Link: https://lkml.kernel.org/r/20201106231635.3528496-8-soheil.kdev@gmail.com
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Khazhismel Kumykov <khazhy@google.com>
Cc: Guantao Liu <guantaol@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is a no-op change which simplifies the follow up patches.
Link: https://lkml.kernel.org/r/20201106231635.3528496-7-soheil.kdev@gmail.com
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Khazhismel Kumykov <khazhy@google.com>
Cc: Guantao Liu <guantaol@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ep_events_available() is called multiple times around the busy loop logic,
even though the logic is generally not used. ep_reset_busy_poll_napi_id()
is similarly always called, even when busy loop is not used.
Eliminate ep_reset_busy_poll_napi_id() and inline it inside
ep_busy_loop(). Make ep_busy_loop() return whether there are any events
available after the busy loop. This will eliminate unnecessary loads and
branches, and simplifies the loop.
Link: https://lkml.kernel.org/r/20201106231635.3528496-6-soheil.kdev@gmail.com
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Khazhismel Kumykov <khazhy@google.com>
Cc: Guantao Liu <guantaol@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is a no-op change and simply to make the code more coherent.
Link: https://lkml.kernel.org/r/20201106231635.3528496-5-soheil.kdev@gmail.com
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Khazhismel Kumykov <khazhy@google.com>
Cc: Guantao Liu <guantaol@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
To simplify the code, pull in checking the fatal signals into
ep_send_events(). ep_send_events() is called only from ep_poll().
Note that, previously, we were always checking fatal events, but it is
checked only if eavail is true. This should be fine because the goal of
that check is to quickly return from epoll_wait() when there is a pending
fatal signal.
Link: https://lkml.kernel.org/r/20201106231635.3528496-4-soheil.kdev@gmail.com
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Suggested-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Khazhismel Kumykov <khazhy@google.com>
Cc: Guantao Liu <guantaol@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Check signals before locking ep->lock, and immediately return -EINTR if
there is any signal pending.
This saves a few loads, stores, and branches from the hot path and
simplifies the loop structure for follow up patches.
Link: https://lkml.kernel.org/r/20201106231635.3528496-3-soheil.kdev@gmail.com
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Khazhismel Kumykov <khazhy@google.com>
Cc: Guantao Liu <guantaol@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "simplify ep_poll".
This patch series is a followup based on the suggestions and feedback by
Linus:
https://lkml.kernel.org/r/CAHk-=wizk=OxUyQPbO8MS41w2Pag1kniUV5WdD5qWL-gq1kjDA@mail.gmail.com
The first patch in the series is a fix for the epoll race in presence of
timeouts, so that it can be cleanly backported to all affected stable
kernels.
The rest of the patch series simplify the ep_poll() implementation. Some
of these simplifications result in minor performance enhancements as well.
We have kept these changes under self tests and internal benchmarks for a
few days, and there are minor (1-2%) performance enhancements as a result.
This patch (of 8):
After abc610e01c ("fs/epoll: avoid barrier after an epoll_wait(2)
timeout"), we break out of the ep_poll loop upon timeout, without checking
whether there is any new events available. Prior to that patch-series we
always called ep_events_available() after exiting the loop.
This can cause races and missed wakeups. For example, consider the
following scenario reported by Guantao Liu:
Suppose we have an eventfd added using EPOLLET to an epollfd.
Thread 1: Sleeps for just below 5ms and then writes to an eventfd.
Thread 2: Calls epoll_wait with a timeout of 5 ms. If it sees an
event of the eventfd, it will write back on that fd.
Thread 3: Calls epoll_wait with a negative timeout.
Prior to abc610e01c, it is guaranteed that Thread 3 will wake up either
by Thread 1 or Thread 2. After abc610e01c, Thread 3 can be blocked
indefinitely if Thread 2 sees a timeout right before the write to the
eventfd by Thread 1. Thread 2 will be woken up from
schedule_hrtimeout_range and, with evail 0, it will not call
ep_send_events().
To fix this issue:
1) Simplify the timed_out case as suggested by Linus.
2) while holding the lock, recheck whether the thread was woken up
after its time out has reached.
Note that (2) is different from Linus' original suggestion: It do not set
"eavail = ep_events_available(ep)" to avoid unnecessary contention (when
there are too many timed-out threads and a small number of events), as
well as races mentioned in the discussion thread.
This is the first patch in the series so that the backport to stable
releases is straightforward.
Link: https://lkml.kernel.org/r/20201106231635.3528496-1-soheil.kdev@gmail.com
Link: https://lkml.kernel.org/r/CAHk-=wizk=OxUyQPbO8MS41w2Pag1kniUV5WdD5qWL-gq1kjDA@mail.gmail.com
Link: https://lkml.kernel.org/r/20201106231635.3528496-2-soheil.kdev@gmail.com
Fixes: abc610e01c ("fs/epoll: avoid barrier after an epoll_wait(2) timeout")
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Tested-by: Guantao Liu <guantaol@google.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Guantao Liu <guantaol@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Khazhismel Kumykov <khazhy@google.com>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After introducing CLOSE_RANGE_CLOEXEC syzbot reported a crash when
CLOSE_RANGE_CLOEXEC is specified in conjunction with CLOSE_RANGE_UNSHARE.
When CLOSE_RANGE_UNSHARE is specified the caller will receive a private
file descriptor table in case their file descriptor table is currently
shared.
For the case where the caller has requested all file descriptors to be
actually closed via e.g. close_range(3, ~0U, 0) the kernel knows that
the caller does not need any of the file descriptors anymore and will
optimize the close operation by only copying all files in the range from
0 to 3 and no others.
However, if the caller requested CLOSE_RANGE_CLOEXEC together with
CLOSE_RANGE_UNSHARE the caller wants to still make use of the file
descriptors so the kernel needs to copy all of them and can't optimize.
The original patch didn't account for this and thus could cause oopses
as evidenced by the syzbot report because it assumed that all fds had
been copied. Fix this by handling the CLOSE_RANGE_CLOEXEC case.
syzbot reported
==================================================================
BUG: KASAN: null-ptr-deref in instrument_atomic_read include/linux/instrumented.h:71 [inline]
BUG: KASAN: null-ptr-deref in atomic64_read include/asm-generic/atomic-instrumented.h:837 [inline]
BUG: KASAN: null-ptr-deref in atomic_long_read include/asm-generic/atomic-long.h:29 [inline]
BUG: KASAN: null-ptr-deref in filp_close+0x22/0x170 fs/open.c:1274
Read of size 8 at addr 0000000000000077 by task syz-executor511/8522
CPU: 1 PID: 8522 Comm: syz-executor511 Not tainted 5.10.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:79 [inline]
dump_stack+0x107/0x163 lib/dump_stack.c:120
__kasan_report mm/kasan/report.c:549 [inline]
kasan_report.cold+0x5/0x37 mm/kasan/report.c:562
check_memory_region_inline mm/kasan/generic.c:186 [inline]
check_memory_region+0x13d/0x180 mm/kasan/generic.c:192
instrument_atomic_read include/linux/instrumented.h:71 [inline]
atomic64_read include/asm-generic/atomic-instrumented.h:837 [inline]
atomic_long_read include/asm-generic/atomic-long.h:29 [inline]
filp_close+0x22/0x170 fs/open.c:1274
close_files fs/file.c:402 [inline]
put_files_struct fs/file.c:417 [inline]
put_files_struct+0x1cc/0x350 fs/file.c:414
exit_files+0x12a/0x170 fs/file.c:435
do_exit+0xb4f/0x2a00 kernel/exit.c:818
do_group_exit+0x125/0x310 kernel/exit.c:920
get_signal+0x428/0x2100 kernel/signal.c:2792
arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:811
handle_signal_work kernel/entry/common.c:147 [inline]
exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
exit_to_user_mode_prepare+0x124/0x200 kernel/entry/common.c:201
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:302
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x447039
Code: Unable to access opcode bytes at RIP 0x44700f.
RSP: 002b:00007f1b1225cdb8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 00000000006dbc28 RCX: 0000000000447039
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00000000006dbc2c
RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c
R13: 00007fff223b6bef R14: 00007f1b1225d9c0 R15: 00000000006dbc2c
==================================================================
syzbot has tested the proposed patch and the reproducer did not trigger any issue:
Reported-and-tested-by: syzbot+96cfd2b22b3213646a93@syzkaller.appspotmail.com
Tested on:
commit: 10f7cddd selftests/core: add regression test for CLOSE_RAN..
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux.git vfs
kernel config: https://syzkaller.appspot.com/x/.config?x=5d42216b510180e3
dashboard link: https://syzkaller.appspot.com/bug?extid=96cfd2b22b3213646a93
compiler: gcc (GCC) 10.1.0-syz 20200507
Reported-by: syzbot+96cfd2b22b3213646a93@syzkaller.appspotmail.com
Fixes: 582f1fb6b7 ("fs, close_range: add flag CLOSE_RANGE_CLOEXEC")
Cc: Giuseppe Scrivano <gscrivan@redhat.com>
Cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/20201217213303.722643-1-christian.brauner@ubuntu.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Fix passing of the additional security info via version
operations. Force new open when getting SACL and avoid
reuse of files that were previously open without
sufficient privileges to access SACLs.
Signed-off-by: Boris Protopopov <pboris@amazon.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
- Introduce a "needsrepair" "feature" to flag a filesystem as needing a
pass through xfs_repair. This is key to enabling filesystem upgrades
(in xfs_db) that require xfs_repair to make minor adjustments to metadata.
- Refactor parameter checking of recovered log intent items so that we
actually use the same validation code as them that generate the intent
items.
- Various fixes to online scrub not reacting correctly to directory
entries pointing to inodes that cannot be igetted.
- Refactor validation helpers for data and rt volume extents.
- Refactor XFS_TRANS_DQ_DIRTY out of existence.
- Fix a longstanding bug where mounting with "uqnoenforce" would start
user quotas in non-enforcing mode but /proc/mounts would display
"usrquota", implying that they are being enforced.
- Don't flag dax+reflink inodes as corruption since that is a valid (but
not fully functional) combination right now.
- Clean up raid stripe validation functions.
- Refactor the inode allocation code to be more straightforward.
- Small prep cleanup for idmapping support.
- Get rid of the xfs_buf_t typedef.
-----BEGIN PGP SIGNATURE-----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=job0
-----END PGP SIGNATURE-----
Merge tag 'xfs-5.11-merge-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs updates from Darrick Wong:
"In this release we add the ability to set a 'needsrepair' flag
indicating that we /know/ the filesystem requires xfs_repair, but
other than that, it's the usual strengthening of metadata validation
and miscellaneous cleanups.
Summary:
- Introduce a "needsrepair" "feature" to flag a filesystem as needing
a pass through xfs_repair. This is key to enabling filesystem
upgrades (in xfs_db) that require xfs_repair to make minor
adjustments to metadata.
- Refactor parameter checking of recovered log intent items so that
we actually use the same validation code as them that generate the
intent items.
- Various fixes to online scrub not reacting correctly to directory
entries pointing to inodes that cannot be igetted.
- Refactor validation helpers for data and rt volume extents.
- Refactor XFS_TRANS_DQ_DIRTY out of existence.
- Fix a longstanding bug where mounting with "uqnoenforce" would
start user quotas in non-enforcing mode but /proc/mounts would
display "usrquota", implying that they are being enforced.
- Don't flag dax+reflink inodes as corruption since that is a valid
(but not fully functional) combination right now.
- Clean up raid stripe validation functions.
- Refactor the inode allocation code to be more straightforward.
- Small prep cleanup for idmapping support.
- Get rid of the xfs_buf_t typedef"
* tag 'xfs-5.11-merge-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (40 commits)
xfs: remove xfs_buf_t typedef
fs/xfs: convert comma to semicolon
xfs: open code updating i_mode in xfs_set_acl
xfs: remove xfs_vn_setattr_nonsize
xfs: kill ialloced in xfs_dialloc()
xfs: spilt xfs_dialloc() into 2 functions
xfs: move xfs_dialloc_roll() into xfs_dialloc()
xfs: move on-disk inode allocation out of xfs_ialloc()
xfs: introduce xfs_dialloc_roll()
xfs: convert noroom, okalloc in xfs_dialloc() to bool
xfs: don't catch dax+reflink inodes as corruption in verifier
xfs: fix the forward progress assertion in xfs_iwalk_run_callbacks
xfs: remove unneeded return value check for *init_cursor()
xfs: introduce xfs_validate_stripe_geometry()
xfs: show the proper user quota options
xfs: remove the unused XFS_B_FSB_OFFSET macro
xfs: remove unnecessary null check in xfs_generic_create
xfs: directly return if the delta equal to zero
xfs: check tp->t_dqinfo value instead of the XFS_TRANS_DQ_DIRTY flag
xfs: delete duplicated tp->t_dqinfo null check and allocation
...
Add SYSTEM_SECURITY access flag and use with smb2 when opening
files for getting/setting SACLs. Add "system.cifs_ntsd_full"
extended attribute to allow user-space access to the functionality.
Avoid multiple server calls when setting owner, DACL, and SACL.
Signed-off-by: Boris Protopopov <pboris@amazon.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
While converting the NFSv4 decoder to use xdr_stream-based XDR
processing, I removed the old SAVEMEM() macro. This macro wrapped
a bit of logic that avoided a memory allocation by recognizing when
the decoded item resides in a linear section of the Receive buffer.
In that case, it returned a pointer into that buffer instead of
allocating a bounce buffer.
The bounce buffer is necessary only when xdr_inline_decode() has
placed the decoded item in the xdr_stream's scratch buffer, which
disappears the next time xdr_inline_decode() is called with that
xdr_stream. That happens only if the data item crosses a page
boundary in the receive buffer, an exceedingly rare occurrence.
Allocating a bounce buffer every time results in a minor performance
regression that was introduced by the recent NFSv4 decoder overhaul.
Let's restore the previous behavior. On average, it saves about 1.5
kmalloc() calls per COMPOUND.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
fs/nfsd/nfssvc.c:36:6: warning: symbol 'inter_copy_offload_enable' was not declared. Should it be static?
The parameter was added by commit ce0887ac96 ("NFSD add nfs4 inter
ssc to nfsd4_copy"). Relocate it into the source file that uses it,
and make it static. This approach is similar to the
nfs4_disable_idmapping, cltrack_prog, and cltrack_legacy_disable
module parameters.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
If the READ_PLUS operation was truncated due to an error, then ensure we
clear the 'eof' flag.
Fixes: 9f0b5792f0 ("NFSD: Encode a full READ_PLUS reply")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Ensure that we encode the data payload + padding, and that we truncate
the preallocated buffer to the actual read size.
Fixes: 528b84934e ("NFSD: Add READ_PLUS data support")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The purpose of io_uring_cancel_files() is to wait for all requests
matching ->files to go/be cancelled. We should first drop files of a
request in io_req_drop_files() and only then make it undiscoverable for
io_uring_cancel_files.
First drop, then delete from list. It's ok to leave req->id->files
dangling, because it's not dereferenced by cancellation code, only
compared against. It would potentially go to sleep and be awaken by
following in io_req_drop_files() wake_up().
Fixes: 0f2122045b ("io_uring: don't rely on weak ->files references")
Cc: <stable@vger.kernel.org> # 5.5+
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
For the first time a req punted to io-wq, we'll initialize io_wq_work's
list to be NULL, then insert req to io_wqe->work_list. If this req is not
inserted into tail of io_wqe->work_list, this req's io_wq_work list will
point to another req's io_wq_work. For splitted bio case, this req maybe
inserted to io_wqe->work_list repeatedly, once we insert it to tail of
io_wqe->work_list for the second time, now io_wq_work->list->next will be
invalid pointer, which then result in many strang error, panic, kernel
soft-lockup, rcu stall, etc.
In my vm, kernel doest not have commit cc29e1bf0d ("block: disable
iopoll for split bio"), below fio job can reproduce this bug steadily:
[global]
name=iouring-sqpoll-iopoll-1
ioengine=io_uring
iodepth=128
numjobs=1
thread
rw=randread
direct=1
registerfiles=1
hipri=1
bs=4m
size=100M
runtime=120
time_based
group_reporting
randrepeat=0
[device]
directory=/home/feiman.wxg/mntpoint/ # an ext4 mount point
If we have commit cc29e1bf0d ("block: disable iopoll for split bio"),
there will no splitted bio case for polled io, but I think we still to need
to fix this list corruption, it also should maybe go to stable branchs.
To fix this corruption, if a req is inserted into tail of io_wqe->work_list,
initialize req->io_wq_work->list->next to bu NULL.
Cc: stable@vger.kernel.org
Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>