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Pull smb client fixes from Steve French:
- copy_file_range fix
- two read fixes including read past end of file rc fix and read retry
crediting fix
- falloc zero range fix
* tag 'v6.11-rc5-smb-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
cifs: Fix FALLOC_FL_ZERO_RANGE to preflush buffered part of target region
cifs: Fix copy offload to flush destination region
netfs, cifs: Fix handling of short DIO read
cifs: Fix lack of credit renegotiation on read retry
Push bcachefs fixes from Kent Overstreet:
"The data corruption in the buffered write path is troubling; inode
lock should not have been able to cause that...
- Fix a rare data corruption in the rebalance path, caught as a nonce
inconsistency on encrypted filesystems
- Revert lockless buffered write path
- Mark more errors as autofix"
* tag 'bcachefs-2024-08-21' of https://github.com/koverstreet/bcachefs:
bcachefs: Mark more errors as autofix
bcachefs: Revert lockless buffered IO path
bcachefs: Fix bch2_extents_match() false positive
bcachefs: Fix failure to return error in data_update_index_update()
Under certain conditions, the range to be cleared by FALLOC_FL_ZERO_RANGE
may only be buffered locally and not yet have been flushed to the server.
For example:
xfs_io -f -t -c "pwrite -S 0x41 0 4k" \
-c "pwrite -S 0x42 4k 4k" \
-c "fzero 0 4k" \
-c "pread -v 0 8k" /xfstest.test/foo
will write two 4KiB blocks of data, which get buffered in the pagecache,
and then fallocate() is used to clear the first 4KiB block on the server -
but we don't flush the data first, which means the EOF position on the
server is wrong, and so the FSCTL_SET_ZERO_DATA RPC fails (and xfs_io
ignores the error), but then when we try to read it, we see the old data.
Fix this by preflushing any part of the target region that above the
server's idea of the EOF position to force the server to update its EOF
position.
Note, however, that we don't want to simply expand the file by moving the
EOF before doing the FSCTL_SET_ZERO_DATA[*] because someone else might see
the zeroed region or if the RPC fails we then have to try to clean it up or
risk getting corruption.
[*] And we have to move the EOF first otherwise FSCTL_SET_ZERO_DATA won't
do what we want.
This fixes the generic/008 xfstest.
[!] Note: A better way to do this might be to split the operation into two
parts: we only do FSCTL_SET_ZERO_DATA for the part of the range below the
server's EOF and then, if that worked, invalidate the buffered pages for the
part above the range.
Fixes: 6b69040247e1 ("cifs/smb3: Fix data inconsistent when zero file range")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <stfrench@microsoft.com>
cc: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
cc: Pavel Shilovsky <pshilov@microsoft.com>
cc: Paulo Alcantara <pc@manguebit.com>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: Rohith Surabattula <rohiths.msft@gmail.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: linux-mm@kvack.org
Signed-off-by: Steve French <stfrench@microsoft.com>
Pull misc fixes from Guenter Roeck.
These are fixes for regressions that Guenther has been reporting, and
the maintainers haven't picked up and sent in. With rc6 fairly imminent,
I'm taking them directly from Guenter.
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
apparmor: fix policy_unpack_test on big endian systems
Revert "MIPS: csrc-r4k: Apply verification clocksource flags"
microblaze: don't treat zero reserved memory regions as error
errors that are known to always be safe to fix should be autofix: this
should be most errors even at this point, but that will need some
thorough review.
note that errors are still logged in the superblock, so we'll still know
that they happened.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Fix cifs_file_copychunk_range() to flush the destination region before
invalidating it to avoid potential loss of data should the copy fail, in
whole or in part, in some way.
Fixes: 7b2404a886f8 ("cifs: Fix flushing, invalidation and file size with copy_file_range()")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <stfrench@microsoft.com>
cc: Paulo Alcantara <pc@manguebit.com>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: Rohith Surabattula <rohiths.msft@gmail.com>
cc: Matthew Wilcox <willy@infradead.org>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: linux-mm@kvack.org
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
Pull power sequencing fix from Bartosz Golaszewski:
"A follow-up fix for the power sequencing subsystem. It turned out the
previous fix for this driver was incomplete and broke the WLAN support
on some platforms. This addresses the issue.
- set the direction of the wlan-enable GPIO to output after
requesting it as-is"
* tag 'pwrseq-fixes-for-v6.11-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux:
power: sequencing: qcom-wcn: set the wlan-enable GPIO to output
policy_unpack_test fails on big endian systems because data byte order
is expected to be little endian but is generated in host byte order.
This results in test failures such as:
# policy_unpack_test_unpack_array_with_null_name: EXPECTATION FAILED at security/apparmor/policy_unpack_test.c:150
Expected array_size == (u16)16, but
array_size == 4096 (0x1000)
(u16)16 == 16 (0x10)
# policy_unpack_test_unpack_array_with_null_name: pass:0 fail:1 skip:0 total:1
not ok 3 policy_unpack_test_unpack_array_with_null_name
# policy_unpack_test_unpack_array_with_name: EXPECTATION FAILED at security/apparmor/policy_unpack_test.c:164
Expected array_size == (u16)16, but
array_size == 4096 (0x1000)
(u16)16 == 16 (0x10)
# policy_unpack_test_unpack_array_with_name: pass:0 fail:1 skip:0 total:1
Add the missing endianness conversions when generating test data.
Fixes: 4d944bcd4e73 ("apparmor: add AppArmor KUnit tests for policy unpack")
Cc: Brendan Higgins <brendanhiggins@google.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
We had a report of data corruption on nixos when building installer
images.
https://github.com/NixOS/nixpkgs/pull/321055#issuecomment-2184131334
It seems that writes are being dropped, but only when issued by QEMU,
and possibly only in snapshot mode. It's undetermined if it's write
calls are being dropped or dirty folios.
Further testing, via minimizing the original patch to just the change
that skips the inode lock on non appends/truncates, reveals that it
really is just not taking the inode lock that causes the corruption: it
has nothing to do with the other logic changes for preserving write
atomicity in corner cases.
It's also kernel config dependent: it doesn't reproduce with the minimal
kernel config that ktest uses, but it does reproduce with nixos's distro
config. Bisection the kernel config initially pointer the finger at page
migration or compaction, but it appears that was erroneous; we haven't
yet determined what kernel config option actually triggers it.
Sadly it appears this will have to be reverted since we're getting too
close to release and my plate is full, but we'd _really_ like to fully
debug it.
My suspicion is that this patch is exposing a preexisting bug - the
inode lock actually covers very little in IO paths, and we have a
different lock (the pagecache add lock) that guards against races with
truncate here.
Fixes: 7e64c86cdc6c ("bcachefs: Buffered write path now can avoid the inode lock")
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Short DIO reads, particularly in relation to cifs, are not being handled
correctly by cifs and netfslib. This can be tested by doing a DIO read of
a file where the size of read is larger than the size of the file. When it
crosses the EOF, it gets a short read and this gets retried, and in the
case of cifs, the retry read fails, with the failure being translated to
ENODATA.
Fix this by the following means:
(1) Add a flag, NETFS_SREQ_HIT_EOF, for the filesystem to set when it
detects that the read did hit the EOF.
(2) Make the netfslib read assessment stop processing subrequests when it
encounters one with that flag set.
(3) Return rreq->transferred, the accumulated contiguous amount read to
that point, to userspace for a DIO read.
(4) Make cifs set the flag and clear the error if the read RPC returned
ENODATA.
(5) Make cifs set the flag and clear the error if a short read occurred
without error and the read-to file position is now at the remote inode
size.
Fixes: 69c3c023af25 ("cifs: Implement netfslib hooks")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <sfrench@samba.org>
cc: Paulo Alcantara <pc@manguebit.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
Pull USB fixes from Greg KH:
"Here are some small USB fixes for 6.11-rc6. Included in here are:
- dwc3 driver fixes for reported issues
- MAINTAINER file update, marking a driver as unsupported :(
- cdnsp driver fixes
- USB gadget driver fix
- USB sysfs fix
- other tiny fixes
- new device ids for usb serial driver
All of these have been in linux-next this week with no reported
issues"
* tag 'usb-6.11-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
USB: serial: option: add MeiG Smart SRM825L
usb: cdnsp: fix for Link TRB with TC
usb: dwc3: st: add missing depopulate in probe error path
usb: dwc3: st: fix probed platform device ref count on probe error path
usb: dwc3: ep0: Don't reset resource alloc flag (including ep0)
usb: core: sysfs: Unmerge @usb3_hardware_lpm_attr_group in remove_power_attributes()
usb: typec: fsa4480: Relax CHIP_ID check
usb: dwc3: xilinx: add missing depopulate in probe error path
usb: dwc3: omap: add missing depopulate in probe error path
dt-bindings: usb: microchip,usb2514: Fix reference USB device schema
usb: gadget: uvc: queue pump work in uvcg_video_enable()
cdc-acm: Add DISABLE_ECHO quirk for GE HealthCare UI Controller
usb: cdnsp: fix incorrect index in cdnsp_get_hw_deq function
usb: dwc3: core: Prevent USB core invalid event buffer address access
MAINTAINERS: Mark UVC gadget driver as orphan
Commit a9aaf1ff88a8 ("power: sequencing: request the WLAN enable GPIO
as-is") broke WLAN on boards on which the wlan-enable GPIO enabling the
wifi module isn't in output mode by default. We need to set direction to
output while retaining the value that was already set to keep the ath
module on if it's already started.
Fixes: a9aaf1ff88a8 ("power: sequencing: request the WLAN enable GPIO as-is")
Link: https://lore.kernel.org/r/20240823115500.37280-1-brgl@bgdev.pl
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
This reverts commit 7190401fc56fb5f02ee3d04476778ab000bbaf32.
Verifying the clock source sometimes deems the MIPS clock
to be unstable, at least in qemu.
clocksource: timekeeping watchdog on CPU0: Marking clocksource 'MIPS' as unstable because the skew is too large:
clocksource: 'jiffies' wd_nsec: 500000000 wd_now: ffff8bde wd_last: ffff8bac mask: ffffffff
clocksource: 'MIPS' cs_nsec: 940634468 cs_now: 310181c4 cs_last: 28090a09 mask: ffffffff
clocksource: Clocksource 'MIPS' skewed 440634468 ns (440 ms) over watchdog 'jiffies' interval of 500000000 ns (500 ms)
clocksource: 'MIPS' is current clocksource.
If this happens, network interfaces fail to come online.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This was caught as a very rare nonce inconsistency, on systems with
encryption and replication (and tiering, or some form of rebalance
operation running):
[Wed Jul 17 13:30:03 2024] about to insert invalid key in data update path
[Wed Jul 17 13:30:03 2024] old: u64s 10 type extent 671283510:6392:U32_MAX len 16 ver 106595503: durability: 2 crc: c_size 8 size 16 offset 0 nonce 0 csum chacha20_poly1305_80 compress zstd ptr: 3:355968:104 gen 7 ptr: 4:513244:48 gen 6 rebalance: target hdd compression zstd
[Wed Jul 17 13:30:03 2024] k: u64s 10 type extent 671283510:6400:U32_MAX len 16 ver 106595508: durability: 2 crc: c_size 8 size 16 offset 0 nonce 0 csum chacha20_poly1305_80 compress zstd ptr: 3:355968:112 gen 7 ptr: 4:513244:56 gen 6 rebalance: target hdd compression zstd
[Wed Jul 17 13:30:03 2024] new: u64s 14 type extent 671283510:6392:U32_MAX len 8 ver 106595508: durability: 2 crc: c_size 8 size 16 offset 0 nonce 0 csum chacha20_poly1305_80 compress zstd ptr: 3:355968:112 gen 7 cached ptr: 4:513244:56 gen 6 cached rebalance: target hdd compression zstd crc: c_size 8 size 16 offset 8 nonce 0 csum chacha20_poly1305_80 compress zstd ptr: 1:10860085:32 gen 0 ptr: 0:17285918:408 gen 0
[Wed Jul 17 13:30:03 2024] bcachefs (cca5bc65-fe77-409d-a9fa-465a6e7f4eae): fatal error - emergency read only
bch2_extents_match() was reporting true for extents that did not
actually point to the same data.
bch2_extent_match() iterates over pairs of pointers, looking for
pointers that point to the same location on disk (with matching
generation numbers). However one or both extents may have been trimmed
(or merged) and they might not have the same disk offset: it corrects
for this by subtracting the key offset and the checksum entry offset.
However, this failed when an extent was immediately partially
overwritten, and the new overwrite was allocated the next adjacent disk
space.
Normally, with compression off, this would never cause a bug, since the
new extent would have to be immediately after the old extent for the
pointer offsets to match, and the rebalance index update path is not
looking for an extent outside the range of the extent it moved.
However with compression enabled, extents take up less space on disk
than they do in the btree index space - and spuriously matching after
partial overwrite is possible.
To fix this, add a secondary check, that strictly checks that the
regions pointed to on disk overlap.
https://github.com/koverstreet/bcachefs/issues/717
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
When netfslib asks cifs to issue a read operation, it prefaces this with a
call to ->clamp_length() which cifs uses to negotiate credits, providing
receive capacity on the server; however, in the event that a read op needs
reissuing, netfslib doesn't call ->clamp_length() again as that could
shorten the subrequest, leaving a gap.
This causes the retried read to be done with zero credits which causes the
server to reject it with STATUS_INVALID_PARAMETER. This is a problem for a
DIO read that is requested that would go over the EOF. The short read will
be retried, causing EINVAL to be returned to the user when it fails.
Fix this by making cifs_req_issue_read() negotiate new credits if retrying
(NETFS_SREQ_RETRYING now gets set in the read side as well as the write
side in this instance).
This isn't sufficient, however: the new credits might not be sufficient to
complete the remainder of the read, so also add an additional field,
rreq->actual_len, that holds the actual size of the op we want to perform
without having to alter subreq->len.
We then rely on repeated short reads being retried until we finish the read
or reach the end of file and make a zero-length read.
Also fix a couple of places where the subrequest start and length need to
be altered by the amount so far transferred when being used.
Fixes: 69c3c023af25 ("cifs: Implement netfslib hooks")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <sfrench@samba.org>
cc: Paulo Alcantara <pc@manguebit.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
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