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Problem

Solution

Testing Done

@palash-gandhi palash-gandhi force-pushed the dlpx/pr/pgandhi-delphix/80025084-36e6-4ac3-abdc-0c86d6dc1648 branch from 7cea140 to d160cc6 Compare May 30, 2023 20:20
delphix-devops-bot pushed a commit that referenced this pull request Jul 24, 2024
BugLink: https://bugs.launchpad.net/bugs/2067974

[ Upstream commit b377add0f0117409c418ddd6504bd682ebe0bf79 ]

Both the function that migrates all the chunks within a region and the
function that migrates all the entries within a chunk call
list_first_entry() on the respective lists without checking that the
lists are not empty. This is incorrect usage of the API, which leads to
the following warning [1].

Fix by returning if the lists are empty as there is nothing to migrate
in this case.

[1]
WARNING: CPU: 0 PID: 6437 at drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_tcam.c:1266 mlxsw_sp_acl_tcam_vchunk_migrate_all+0x1f1/0>
Modules linked in:
CPU: 0 PID: 6437 Comm: kworker/0:37 Not tainted 6.9.0-rc3-custom-00883-g94a65f079ef6 #39
Hardware name: Mellanox Technologies Ltd. MSN3700/VMOD0005, BIOS 5.11 01/06/2019
Workqueue: mlxsw_core mlxsw_sp_acl_tcam_vregion_rehash_work
RIP: 0010:mlxsw_sp_acl_tcam_vchunk_migrate_all+0x1f1/0x2c0
[...]
Call Trace:
 <TASK>
 mlxsw_sp_acl_tcam_vregion_rehash_work+0x6c/0x4a0
 process_one_work+0x151/0x370
 worker_thread+0x2cb/0x3e0
 kthread+0xd0/0x100
 ret_from_fork+0x34/0x50
 ret_from_fork_asm+0x1a/0x30
 </TASK>

Fixes: 6f9579d ("mlxsw: spectrum_acl: Remember where to continue rehash migration")
Signed-off-by: Ido Schimmel <[email protected]>
Tested-by: Alexander Zubkov <[email protected]>
Reviewed-by: Petr Machata <[email protected]>
Signed-off-by: Petr Machata <[email protected]>
Reviewed-by: Simon Horman <[email protected]>
Link: https://lore.kernel.org/r/4628e9a22d1d84818e28310abbbc498e7bc31bc9.1713797103.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
Signed-off-by: Portia Stephens <[email protected]>
Signed-off-by: Stefan Bader <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request Mar 29, 2025
BugLink: https://bugs.launchpad.net/bugs/2097298

[ Upstream commit fcede1f0a043ccefe9bc6ad57f12718e42f63f1d ]

Our syzkaller report a following UAF for v6.6:

BUG: KASAN: slab-use-after-free in bfq_init_rq+0x175d/0x17a0 block/bfq-iosched.c:6958
Read of size 8 at addr ffff8881b57147d8 by task fsstress/232726

CPU: 2 PID: 232726 Comm: fsstress Not tainted 6.6.0-g3629d1885222 #39
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x91/0xf0 lib/dump_stack.c:106
 print_address_description.constprop.0+0x66/0x300 mm/kasan/report.c:364
 print_report+0x3e/0x70 mm/kasan/report.c:475
 kasan_report+0xb8/0xf0 mm/kasan/report.c:588
 hlist_add_head include/linux/list.h:1023 [inline]
 bfq_init_rq+0x175d/0x17a0 block/bfq-iosched.c:6958
 bfq_insert_request.isra.0+0xe8/0xa20 block/bfq-iosched.c:6271
 bfq_insert_requests+0x27f/0x390 block/bfq-iosched.c:6323
 blk_mq_insert_request+0x290/0x8f0 block/blk-mq.c:2660
 blk_mq_submit_bio+0x1021/0x15e0 block/blk-mq.c:3143
 __submit_bio+0xa0/0x6b0 block/blk-core.c:639
 __submit_bio_noacct_mq block/blk-core.c:718 [inline]
 submit_bio_noacct_nocheck+0x5b7/0x810 block/blk-core.c:747
 submit_bio_noacct+0xca0/0x1990 block/blk-core.c:847
 __ext4_read_bh fs/ext4/super.c:205 [inline]
 ext4_read_bh+0x15e/0x2e0 fs/ext4/super.c:230
 __read_extent_tree_block+0x304/0x6f0 fs/ext4/extents.c:567
 ext4_find_extent+0x479/0xd20 fs/ext4/extents.c:947
 ext4_ext_map_blocks+0x1a3/0x2680 fs/ext4/extents.c:4182
 ext4_map_blocks+0x929/0x15a0 fs/ext4/inode.c:660
 ext4_iomap_begin_report+0x298/0x480 fs/ext4/inode.c:3569
 iomap_iter+0x3dd/0x1010 fs/iomap/iter.c:91
 iomap_fiemap+0x1f4/0x360 fs/iomap/fiemap.c:80
 ext4_fiemap+0x181/0x210 fs/ext4/extents.c:5051
 ioctl_fiemap.isra.0+0x1b4/0x290 fs/ioctl.c:220
 do_vfs_ioctl+0x31c/0x11a0 fs/ioctl.c:811
 __do_sys_ioctl fs/ioctl.c:869 [inline]
 __se_sys_ioctl+0xae/0x190 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x70/0x120 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x78/0xe2

Allocated by task 232719:
 kasan_save_stack+0x22/0x50 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 __kasan_slab_alloc+0x87/0x90 mm/kasan/common.c:328
 kasan_slab_alloc include/linux/kasan.h:188 [inline]
 slab_post_alloc_hook mm/slab.h:768 [inline]
 slab_alloc_node mm/slub.c:3492 [inline]
 kmem_cache_alloc_node+0x1b8/0x6f0 mm/slub.c:3537
 bfq_get_queue+0x215/0x1f00 block/bfq-iosched.c:5869
 bfq_get_bfqq_handle_split+0x167/0x5f0 block/bfq-iosched.c:6776
 bfq_init_rq+0x13a4/0x17a0 block/bfq-iosched.c:6938
 bfq_insert_request.isra.0+0xe8/0xa20 block/bfq-iosched.c:6271
 bfq_insert_requests+0x27f/0x390 block/bfq-iosched.c:6323
 blk_mq_insert_request+0x290/0x8f0 block/blk-mq.c:2660
 blk_mq_submit_bio+0x1021/0x15e0 block/blk-mq.c:3143
 __submit_bio+0xa0/0x6b0 block/blk-core.c:639
 __submit_bio_noacct_mq block/blk-core.c:718 [inline]
 submit_bio_noacct_nocheck+0x5b7/0x810 block/blk-core.c:747
 submit_bio_noacct+0xca0/0x1990 block/blk-core.c:847
 __ext4_read_bh fs/ext4/super.c:205 [inline]
 ext4_read_bh_nowait+0x15a/0x240 fs/ext4/super.c:217
 ext4_read_bh_lock+0xac/0xd0 fs/ext4/super.c:242
 ext4_bread_batch+0x268/0x500 fs/ext4/inode.c:958
 __ext4_find_entry+0x448/0x10f0 fs/ext4/namei.c:1671
 ext4_lookup_entry fs/ext4/namei.c:1774 [inline]
 ext4_lookup.part.0+0x359/0x6f0 fs/ext4/namei.c:1842
 ext4_lookup+0x72/0x90 fs/ext4/namei.c:1839
 __lookup_slow+0x257/0x480 fs/namei.c:1696
 lookup_slow fs/namei.c:1713 [inline]
 walk_component+0x454/0x5c0 fs/namei.c:2004
 link_path_walk.part.0+0x773/0xda0 fs/namei.c:2331
 link_path_walk fs/namei.c:3826 [inline]
 path_openat+0x1b9/0x520 fs/namei.c:3826
 do_filp_open+0x1b7/0x400 fs/namei.c:3857
 do_sys_openat2+0x5dc/0x6e0 fs/open.c:1428
 do_sys_open fs/open.c:1443 [inline]
 __do_sys_openat fs/open.c:1459 [inline]
 __se_sys_openat fs/open.c:1454 [inline]
 __x64_sys_openat+0x148/0x200 fs/open.c:1454
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x70/0x120 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x78/0xe2

Freed by task 232726:
 kasan_save_stack+0x22/0x50 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 kasan_save_free_info+0x2b/0x50 mm/kasan/generic.c:522
 ____kasan_slab_free mm/kasan/common.c:236 [inline]
 __kasan_slab_free+0x12a/0x1b0 mm/kasan/common.c:244
 kasan_slab_free include/linux/kasan.h:164 [inline]
 slab_free_hook mm/slub.c:1827 [inline]
 slab_free_freelist_hook mm/slub.c:1853 [inline]
 slab_free mm/slub.c:3820 [inline]
 kmem_cache_free+0x110/0x760 mm/slub.c:3842
 bfq_put_queue+0x6a7/0xfb0 block/bfq-iosched.c:5428
 bfq_forget_entity block/bfq-wf2q.c:634 [inline]
 bfq_put_idle_entity+0x142/0x240 block/bfq-wf2q.c:645
 bfq_forget_idle+0x189/0x1e0 block/bfq-wf2q.c:671
 bfq_update_vtime block/bfq-wf2q.c:1280 [inline]
 __bfq_lookup_next_entity block/bfq-wf2q.c:1374 [inline]
 bfq_lookup_next_entity+0x350/0x480 block/bfq-wf2q.c:1433
 bfq_update_next_in_service+0x1c0/0x4f0 block/bfq-wf2q.c:128
 bfq_deactivate_entity+0x10a/0x240 block/bfq-wf2q.c:1188
 bfq_deactivate_bfqq block/bfq-wf2q.c:1592 [inline]
 bfq_del_bfqq_busy+0x2e8/0xad0 block/bfq-wf2q.c:1659
 bfq_release_process_ref+0x1cc/0x220 block/bfq-iosched.c:3139
 bfq_split_bfqq+0x481/0xdf0 block/bfq-iosched.c:6754
 bfq_init_rq+0xf29/0x17a0 block/bfq-iosched.c:6934
 bfq_insert_request.isra.0+0xe8/0xa20 block/bfq-iosched.c:6271
 bfq_insert_requests+0x27f/0x390 block/bfq-iosched.c:6323
 blk_mq_insert_request+0x290/0x8f0 block/blk-mq.c:2660
 blk_mq_submit_bio+0x1021/0x15e0 block/blk-mq.c:3143
 __submit_bio+0xa0/0x6b0 block/blk-core.c:639
 __submit_bio_noacct_mq block/blk-core.c:718 [inline]
 submit_bio_noacct_nocheck+0x5b7/0x810 block/blk-core.c:747
 submit_bio_noacct+0xca0/0x1990 block/blk-core.c:847
 __ext4_read_bh fs/ext4/super.c:205 [inline]
 ext4_read_bh+0x15e/0x2e0 fs/ext4/super.c:230
 __read_extent_tree_block+0x304/0x6f0 fs/ext4/extents.c:567
 ext4_find_extent+0x479/0xd20 fs/ext4/extents.c:947
 ext4_ext_map_blocks+0x1a3/0x2680 fs/ext4/extents.c:4182
 ext4_map_blocks+0x929/0x15a0 fs/ext4/inode.c:660
 ext4_iomap_begin_report+0x298/0x480 fs/ext4/inode.c:3569
 iomap_iter+0x3dd/0x1010 fs/iomap/iter.c:91
 iomap_fiemap+0x1f4/0x360 fs/iomap/fiemap.c:80
 ext4_fiemap+0x181/0x210 fs/ext4/extents.c:5051
 ioctl_fiemap.isra.0+0x1b4/0x290 fs/ioctl.c:220
 do_vfs_ioctl+0x31c/0x11a0 fs/ioctl.c:811
 __do_sys_ioctl fs/ioctl.c:869 [inline]
 __se_sys_ioctl+0xae/0x190 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x70/0x120 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x78/0xe2

commit 1ba0403ac644 ("block, bfq: fix uaf for accessing waker_bfqq after
splitting") fix the problem that if waker_bfqq is in the merge chain,
and current is the only procress, waker_bfqq can be freed from
bfq_split_bfqq(). However, the case that waker_bfqq is not in the merge
chain is missed, and if the procress reference of waker_bfqq is 0,
waker_bfqq can be freed as well.

Fix the problem by checking procress reference if waker_bfqq is not in
the merge_chain.

Fixes: 1ba0403ac644 ("block, bfq: fix uaf for accessing waker_bfqq after splitting")
Signed-off-by: Hou Tao <[email protected]>
Signed-off-by: Yu Kuai <[email protected]>
Reviewed-by: Jan Kara <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
Signed-off-by: Noah Wager <[email protected]>
Signed-off-by: Koichiro Den <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request May 17, 2025
BugLink: https://bugs.launchpad.net/bugs/2106770

[ Upstream commit fcede1f0a043ccefe9bc6ad57f12718e42f63f1d ]

Our syzkaller report a following UAF for v6.6:

BUG: KASAN: slab-use-after-free in bfq_init_rq+0x175d/0x17a0 block/bfq-iosched.c:6958
Read of size 8 at addr ffff8881b57147d8 by task fsstress/232726

CPU: 2 PID: 232726 Comm: fsstress Not tainted 6.6.0-g3629d1885222 #39
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x91/0xf0 lib/dump_stack.c:106
 print_address_description.constprop.0+0x66/0x300 mm/kasan/report.c:364
 print_report+0x3e/0x70 mm/kasan/report.c:475
 kasan_report+0xb8/0xf0 mm/kasan/report.c:588
 hlist_add_head include/linux/list.h:1023 [inline]
 bfq_init_rq+0x175d/0x17a0 block/bfq-iosched.c:6958
 bfq_insert_request.isra.0+0xe8/0xa20 block/bfq-iosched.c:6271
 bfq_insert_requests+0x27f/0x390 block/bfq-iosched.c:6323
 blk_mq_insert_request+0x290/0x8f0 block/blk-mq.c:2660
 blk_mq_submit_bio+0x1021/0x15e0 block/blk-mq.c:3143
 __submit_bio+0xa0/0x6b0 block/blk-core.c:639
 __submit_bio_noacct_mq block/blk-core.c:718 [inline]
 submit_bio_noacct_nocheck+0x5b7/0x810 block/blk-core.c:747
 submit_bio_noacct+0xca0/0x1990 block/blk-core.c:847
 __ext4_read_bh fs/ext4/super.c:205 [inline]
 ext4_read_bh+0x15e/0x2e0 fs/ext4/super.c:230
 __read_extent_tree_block+0x304/0x6f0 fs/ext4/extents.c:567
 ext4_find_extent+0x479/0xd20 fs/ext4/extents.c:947
 ext4_ext_map_blocks+0x1a3/0x2680 fs/ext4/extents.c:4182
 ext4_map_blocks+0x929/0x15a0 fs/ext4/inode.c:660
 ext4_iomap_begin_report+0x298/0x480 fs/ext4/inode.c:3569
 iomap_iter+0x3dd/0x1010 fs/iomap/iter.c:91
 iomap_fiemap+0x1f4/0x360 fs/iomap/fiemap.c:80
 ext4_fiemap+0x181/0x210 fs/ext4/extents.c:5051
 ioctl_fiemap.isra.0+0x1b4/0x290 fs/ioctl.c:220
 do_vfs_ioctl+0x31c/0x11a0 fs/ioctl.c:811
 __do_sys_ioctl fs/ioctl.c:869 [inline]
 __se_sys_ioctl+0xae/0x190 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x70/0x120 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x78/0xe2

Allocated by task 232719:
 kasan_save_stack+0x22/0x50 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 __kasan_slab_alloc+0x87/0x90 mm/kasan/common.c:328
 kasan_slab_alloc include/linux/kasan.h:188 [inline]
 slab_post_alloc_hook mm/slab.h:768 [inline]
 slab_alloc_node mm/slub.c:3492 [inline]
 kmem_cache_alloc_node+0x1b8/0x6f0 mm/slub.c:3537
 bfq_get_queue+0x215/0x1f00 block/bfq-iosched.c:5869
 bfq_get_bfqq_handle_split+0x167/0x5f0 block/bfq-iosched.c:6776
 bfq_init_rq+0x13a4/0x17a0 block/bfq-iosched.c:6938
 bfq_insert_request.isra.0+0xe8/0xa20 block/bfq-iosched.c:6271
 bfq_insert_requests+0x27f/0x390 block/bfq-iosched.c:6323
 blk_mq_insert_request+0x290/0x8f0 block/blk-mq.c:2660
 blk_mq_submit_bio+0x1021/0x15e0 block/blk-mq.c:3143
 __submit_bio+0xa0/0x6b0 block/blk-core.c:639
 __submit_bio_noacct_mq block/blk-core.c:718 [inline]
 submit_bio_noacct_nocheck+0x5b7/0x810 block/blk-core.c:747
 submit_bio_noacct+0xca0/0x1990 block/blk-core.c:847
 __ext4_read_bh fs/ext4/super.c:205 [inline]
 ext4_read_bh_nowait+0x15a/0x240 fs/ext4/super.c:217
 ext4_read_bh_lock+0xac/0xd0 fs/ext4/super.c:242
 ext4_bread_batch+0x268/0x500 fs/ext4/inode.c:958
 __ext4_find_entry+0x448/0x10f0 fs/ext4/namei.c:1671
 ext4_lookup_entry fs/ext4/namei.c:1774 [inline]
 ext4_lookup.part.0+0x359/0x6f0 fs/ext4/namei.c:1842
 ext4_lookup+0x72/0x90 fs/ext4/namei.c:1839
 __lookup_slow+0x257/0x480 fs/namei.c:1696
 lookup_slow fs/namei.c:1713 [inline]
 walk_component+0x454/0x5c0 fs/namei.c:2004
 link_path_walk.part.0+0x773/0xda0 fs/namei.c:2331
 link_path_walk fs/namei.c:3826 [inline]
 path_openat+0x1b9/0x520 fs/namei.c:3826
 do_filp_open+0x1b7/0x400 fs/namei.c:3857
 do_sys_openat2+0x5dc/0x6e0 fs/open.c:1428
 do_sys_open fs/open.c:1443 [inline]
 __do_sys_openat fs/open.c:1459 [inline]
 __se_sys_openat fs/open.c:1454 [inline]
 __x64_sys_openat+0x148/0x200 fs/open.c:1454
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x70/0x120 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x78/0xe2

Freed by task 232726:
 kasan_save_stack+0x22/0x50 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 kasan_save_free_info+0x2b/0x50 mm/kasan/generic.c:522
 ____kasan_slab_free mm/kasan/common.c:236 [inline]
 __kasan_slab_free+0x12a/0x1b0 mm/kasan/common.c:244
 kasan_slab_free include/linux/kasan.h:164 [inline]
 slab_free_hook mm/slub.c:1827 [inline]
 slab_free_freelist_hook mm/slub.c:1853 [inline]
 slab_free mm/slub.c:3820 [inline]
 kmem_cache_free+0x110/0x760 mm/slub.c:3842
 bfq_put_queue+0x6a7/0xfb0 block/bfq-iosched.c:5428
 bfq_forget_entity block/bfq-wf2q.c:634 [inline]
 bfq_put_idle_entity+0x142/0x240 block/bfq-wf2q.c:645
 bfq_forget_idle+0x189/0x1e0 block/bfq-wf2q.c:671
 bfq_update_vtime block/bfq-wf2q.c:1280 [inline]
 __bfq_lookup_next_entity block/bfq-wf2q.c:1374 [inline]
 bfq_lookup_next_entity+0x350/0x480 block/bfq-wf2q.c:1433
 bfq_update_next_in_service+0x1c0/0x4f0 block/bfq-wf2q.c:128
 bfq_deactivate_entity+0x10a/0x240 block/bfq-wf2q.c:1188
 bfq_deactivate_bfqq block/bfq-wf2q.c:1592 [inline]
 bfq_del_bfqq_busy+0x2e8/0xad0 block/bfq-wf2q.c:1659
 bfq_release_process_ref+0x1cc/0x220 block/bfq-iosched.c:3139
 bfq_split_bfqq+0x481/0xdf0 block/bfq-iosched.c:6754
 bfq_init_rq+0xf29/0x17a0 block/bfq-iosched.c:6934
 bfq_insert_request.isra.0+0xe8/0xa20 block/bfq-iosched.c:6271
 bfq_insert_requests+0x27f/0x390 block/bfq-iosched.c:6323
 blk_mq_insert_request+0x290/0x8f0 block/blk-mq.c:2660
 blk_mq_submit_bio+0x1021/0x15e0 block/blk-mq.c:3143
 __submit_bio+0xa0/0x6b0 block/blk-core.c:639
 __submit_bio_noacct_mq block/blk-core.c:718 [inline]
 submit_bio_noacct_nocheck+0x5b7/0x810 block/blk-core.c:747
 submit_bio_noacct+0xca0/0x1990 block/blk-core.c:847
 __ext4_read_bh fs/ext4/super.c:205 [inline]
 ext4_read_bh+0x15e/0x2e0 fs/ext4/super.c:230
 __read_extent_tree_block+0x304/0x6f0 fs/ext4/extents.c:567
 ext4_find_extent+0x479/0xd20 fs/ext4/extents.c:947
 ext4_ext_map_blocks+0x1a3/0x2680 fs/ext4/extents.c:4182
 ext4_map_blocks+0x929/0x15a0 fs/ext4/inode.c:660
 ext4_iomap_begin_report+0x298/0x480 fs/ext4/inode.c:3569
 iomap_iter+0x3dd/0x1010 fs/iomap/iter.c:91
 iomap_fiemap+0x1f4/0x360 fs/iomap/fiemap.c:80
 ext4_fiemap+0x181/0x210 fs/ext4/extents.c:5051
 ioctl_fiemap.isra.0+0x1b4/0x290 fs/ioctl.c:220
 do_vfs_ioctl+0x31c/0x11a0 fs/ioctl.c:811
 __do_sys_ioctl fs/ioctl.c:869 [inline]
 __se_sys_ioctl+0xae/0x190 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x70/0x120 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x78/0xe2

commit 1ba0403ac644 ("block, bfq: fix uaf for accessing waker_bfqq after
splitting") fix the problem that if waker_bfqq is in the merge chain,
and current is the only procress, waker_bfqq can be freed from
bfq_split_bfqq(). However, the case that waker_bfqq is not in the merge
chain is missed, and if the procress reference of waker_bfqq is 0,
waker_bfqq can be freed as well.

Fix the problem by checking procress reference if waker_bfqq is not in
the merge_chain.

Fixes: 1ba0403ac644 ("block, bfq: fix uaf for accessing waker_bfqq after splitting")
Signed-off-by: Hou Tao <[email protected]>
Signed-off-by: Yu Kuai <[email protected]>
Reviewed-by: Jan Kara <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
CVE-2025-21631
Signed-off-by: Manuel Diewald <[email protected]>
Signed-off-by: Mehmet Basaran <[email protected]>
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