Merge tag 'v6.6.48' into for/openbmc/dev-6.6

This is the 6.6.48 stable release

fs/netfs/fscache_cookie: add missing "n_accesses" check

commit f71aa06398aabc2e3eaac25acdf3d62e0094ba70 upstream.

This fixes a NULL pointer dereference bug due to a data race which
looks like this:

fs/netfs/fscache_cookie: add missing "n_accesses" check

commit f71aa06398aabc2e3eaac25acdf3d62e0094ba70 upstream.

This fixes a NULL pointer dereference bug due to a data race which
looks like this:

BUG: kernel NULL pointer dereference, address: 0000000000000008
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] SMP PTI
CPU: 33 PID: 16573 Comm: kworker/u97:799 Not tainted 6.8.7-cm4all1-hp+ #43
Hardware name: HP ProLiant DL380 Gen9/ProLiant DL380 Gen9, BIOS P89 10/17/2018
Workqueue: events_unbound netfs_rreq_write_to_cache_work
RIP: 0010:cachefiles_prepare_write+0x30/0xa0
Code: 57 41 56 45 89 ce 41 55 49 89 cd 41 54 49 89 d4 55 53 48 89 fb 48 83 ec 08 48 8b 47 08 48 83 7f 10 00 48 89 34 24 48 8b 68 20 <48> 8b 45 08 4c 8b 38 74 45 49 8b 7f 50 e8 4e a9 b0 ff 48 8b 73 10
RSP: 0018:ffffb4e78113bde0 EFLAGS: 00010286
RAX: ffff976126be6d10 RBX: ffff97615cdb8438 RCX: 0000000000020000
RDX: ffff97605e6c4c68 RSI: ffff97605e6c4c60 RDI: ffff97615cdb8438
RBP: 0000000000000000 R08: 0000000000278333 R09: 0000000000000001
R10: ffff97605e6c4600 R11: 0000000000000001 R12: ffff97605e6c4c68
R13: 0000000000020000 R14: 0000000000000001 R15: ffff976064fe2c00
FS: 0000000000000000(0000) GS:ffff9776dfd40000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000008 CR3: 000000005942c002 CR4: 00000000001706f0
Call Trace:
<TASK>
? __die+0x1f/0x70
? page_fault_oops+0x15d/0x440
? search_module_extables+0xe/0x40
? fixup_exception+0x22/0x2f0
? exc_page_fault+0x5f/0x100
? asm_exc_page_fault+0x22/0x30
? cachefiles_prepare_write+0x30/0xa0
netfs_rreq_write_to_cache_work+0x135/0x2e0
process_one_work+0x137/0x2c0
worker_thread+0x2e9/0x400
? __pfx_worker_thread+0x10/0x10
kthread+0xcc/0x100
? __pfx_kthread+0x10/0x10
ret_from_fork+0x30/0x50
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1b/0x30
</TASK>
Modules linked in:
CR2: 0000000000000008
---[ end trace 0000000000000000 ]---

This happened because fscache_cookie_state_machine() was slow and was
still running while another process invoked fscache_unuse_cookie();
this led to a fscache_cookie_lru_do_one() call, setting the
FSCACHE_COOKIE_DO_LRU_DISCARD flag, which was picked up by
fscache_cookie_state_machine(), withdrawing the cookie via
cachefiles_withdraw_cookie(), clearing cookie->cache_priv.

At the same time, yet another process invoked
cachefiles_prepare_write(), which found a NULL pointer in this code
line:

struct cachefiles_object *object = cachefiles_cres_object(cres);

The next line crashes, obviously:

struct cachefiles_cache *cache = object->volume->cache;

During cachefiles_prepare_write(), the "n_accesses" counter is
non-zero (via fscache_begin_operation()). The cookie must not be
withdrawn until it drops to zero.

The counter is checked by fscache_cookie_state_machine() before
switching to FSCACHE_COOKIE_STATE_RELINQUISHING and
FSCACHE_COOKIE_STATE_WITHDRAWING (in "case
FSCACHE_COOKIE_STATE_FAILED"), but not for
FSCACHE_COOKIE_STATE_LRU_DISCARDING ("case
FSCACHE_COOKIE_STATE_ACTIVE").

This patch adds the missing check. With a non-zero access counter,
the function returns and the next fscache_end_cookie_access() call
will queue another fscache_cookie_state_machine() call to handle the
still-pending FSCACHE_COOKIE_DO_LRU_DISCARD.

Fixes: 12bb21a29c19 ("fscache: Implement cookie user counting and resource pinning")
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20240729162002.3436763-2-dhowells@redhat.com
cc: Jeff Layton <jlayton@kernel.org>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
cc: stable@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

Merge branch 'next' into for-linus

Prepare input updates for 6.3 merge window.

Merge drm/drm-next into drm-misc-next

Backmerging into drm-misc-next to get DRM accelerator infrastructure,
which is required by ipuv driver.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Merge tag 'v6.2-rc3' into next

Merge with mainline to bring in timer_shutdown_sync() API.

Merge drm/drm-fixes into drm-misc-fixes

Let's start the fixes cycle.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>

Merge drm/drm-next into drm-intel-next

Sync up with v6.2-rc1.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>

Merge drm/drm-next into drm-intel-gt-next

Sync after v6.2-rc1 landed in drm-next.

We need to get some dependencies in place before we can merge
the fixes series from Gwan-gyeong and Chris.

Referen

Merge drm/drm-next into drm-intel-gt-next

Sync after v6.2-rc1 landed in drm-next.

We need to get some dependencies in place before we can merge
the fixes series from Gwan-gyeong and Chris.

References: https://lore.kernel.org/all/Y6x5JCDnh2rvh4lA@intel.com/
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

show more ...

Merge tag 'v6.2-rc1' into media_tree

Linux 6.2-rc1

* tag 'v6.2-rc1': (14398 commits)
Linux 6.2-rc1
treewide: Convert del_timer*() to timer_shutdown*()
pstore: Properly assign mem_type propert

Merge tag 'v6.2-rc1' into media_tree

Linux 6.2-rc1

* tag 'v6.2-rc1': (14398 commits)
Linux 6.2-rc1
treewide: Convert del_timer*() to timer_shutdown*()
pstore: Properly assign mem_type property
pstore: Make sure CONFIG_PSTORE_PMSG selects CONFIG_RT_MUTEXES
cfi: Fix CFI failure with KASAN
perf python: Fix splitting CC into compiler and options
afs: Stop implementing ->writepage()
afs: remove afs_cache_netfs and afs_zap_permits() declarations
afs: remove variable nr_servers
afs: Fix lost servers_outstanding count
ALSA: usb-audio: Add new quirk FIXED_RATE for JBL Quantum810 Wireless
ALSA: azt3328: Remove the unused function snd_azf3328_codec_outl()
gcov: add support for checksum field
test_maple_tree: add test for mas_spanning_rebalance() on insufficient data
maple_tree: fix mas_spanning_rebalance() on insufficient data
hugetlb: really allocate vma lock for all sharable vmas
kmsan: export kmsan_handle_urb
kmsan: include linux/vmalloc.h
mm/mempolicy: fix memory leak in set_mempolicy_home_node system call
mm, mremap: fix mremap() expanding vma with addr inside vma
...

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Merge remote-tracking branch 'torvalds/master' into perf/core

To resolve a trivial merge conflict with c302378bc157f6a7 ("libbpf:
Hashmap interface update to allow both long and void* keys/values"),

Merge remote-tracking branch 'torvalds/master' into perf/core

To resolve a trivial merge conflict with c302378bc157f6a7 ("libbpf:
Hashmap interface update to allow both long and void* keys/values"),
where a function present upstream was removed in the perf tools
development tree.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

show more ...

Merge branch 'main' into zstd-linus

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>

fscache: Fix oops due to race with cookie_lru and use_cookie

If a cookie expires from the LRU and the LRU_DISCARD flag is set, but
the state machine has not run yet, it's possible another thread can

fscache: Fix oops due to race with cookie_lru and use_cookie

If a cookie expires from the LRU and the LRU_DISCARD flag is set, but
the state machine has not run yet, it's possible another thread can call
fscache_use_cookie and begin to use it.

When the cookie_worker finally runs, it will see the LRU_DISCARD flag
set, transition the cookie->state to LRU_DISCARDING, which will then
withdraw the cookie. Once the cookie is withdrawn the object is removed
the below oops will occur because the object associated with the cookie
is now NULL.

Fix the oops by clearing the LRU_DISCARD bit if another thread uses the
cookie before the cookie_worker runs.

BUG: kernel NULL pointer dereference, address: 0000000000000008
...
CPU: 31 PID: 44773 Comm: kworker/u130:1 Tainted: G E 6.0.0-5.dneg.x86_64 #1
Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
Workqueue: events_unbound netfs_rreq_write_to_cache_work [netfs]
RIP: 0010:cachefiles_prepare_write+0x28/0x90 [cachefiles]
...
Call Trace:
netfs_rreq_write_to_cache_work+0x11c/0x320 [netfs]
process_one_work+0x217/0x3e0
worker_thread+0x4a/0x3b0
kthread+0xd6/0x100

Fixes: 12bb21a29c19 ("fscache: Implement cookie user counting and resource pinning")
Reported-by: Daire Byrne <daire.byrne@gmail.com>
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Daire Byrne <daire@dneg.com>
Link: https://lore.kernel.org/r/20221117115023.1350181-1-dwysocha@redhat.com/ # v1
Link: https://lore.kernel.org/r/20221117142915.1366990-1-dwysocha@redhat.com/ # v2
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

Merge branch 'main' into zstd-next

Merge branch 'next' into for-linus

Prepare input updates for 6.1 merge window.

Merge branch 'for-6.1/logitech' into for-linus

- Add hanlding of all Bluetooth HID++ devices and fixes in hid++
(Bastien Nocera)

Merge drm/drm-next into drm-intel-gt-next

Daniele needs 84d4333c1e28 ("misc/mei: Add NULL check to component match
callback functions") in order to merge the DG2 HuC patches.

Signed-off-by: Tvrtko

Merge drm/drm-next into drm-intel-gt-next

Daniele needs 84d4333c1e28 ("misc/mei: Add NULL check to component match
callback functions") in order to merge the DG2 HuC patches.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

show more ...

Merge branch 'for-6.1/nvdimm' into libnvdimm-for-next

Add v6.1 content on top of some straggling updates that missed v6.0.

Merge branch 'mlx5-vfio' into mlx5-next

Merge net/mlx5 dependencies for device DMA logging.

Signed-off-by: Leon Romanovsky <leonro@nvidia.com>

Merge branch 'for-6.0/dax' into libnvdimm-fixes

Pick up another "Soft Reservation" fix for v6.0-final on top of some
straggling nvdimm fixes that missed v5.19.

Merge tag 'v6.0-rc6' into locking/core, to refresh the branch

Signed-off-by: Ingo Molnar <mingo@kernel.org>

Merge drm/drm-next into drm-misc-next

We need 6.0-rc1 to merge the backlight rework PR.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>

Merge branch 'am5748-fix' into fixes

Merge branch 'linus' into x86/mm, to refresh the branch

This branch is ~14k commits behind upstream, and has an old merge base
from early into the merge window, refresh it to v6.0-rc3+fixes before
q

Merge branch 'linus' into x86/mm, to refresh the branch

This branch is ~14k commits behind upstream, and has an old merge base
from early into the merge window, refresh it to v6.0-rc3+fixes before
queueing up new commits.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

show more ...

Merge branch 'sched/warnings' into sched/core, to pick up WARN_ON_ONCE() conversion commit

Merge in the BUG_ON() => WARN_ON_ONCE() conversion commit.

Signed-off-by: Ingo Molnar <mingo@kernel.org>