linux/block
Yu Kuai f587c1ac68 block, bfq: fix waker_bfqq UAF after bfq_split_bfqq()
[ Upstream commit fcede1f0a0 ]

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 1ba0403ac6 ("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: 1ba0403ac6 ("block, bfq: fix uaf for accessing waker_bfqq after splitting")
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20250108084148.1549973-1-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
History 2025-01-23 17:15:55 +01:00
..
partitions block: fix potential invalid pointer dereference in blk_add_partition 2024-10-17 15:10:48 +02:00
badblocks.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
bdev.c block: move GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE to disk->event_flags 2023-09-19 12:23:02 +02:00
bfq-cgroup.c block, bfq: fix uaf for bfqq in bic_set_bfqq() 2023-02-09 11:26:36 +01:00
bfq-iosched.c block, bfq: fix waker_bfqq UAF after bfq_split_bfqq() 2025-01-23 17:15:55 +01:00
bfq-iosched.h bfq: Get rid of __bio_blkcg() usage 2022-06-09 10:23:19 +02:00
bfq-wf2q.c block/bfq_wf2q: correct weight to ioprio 2022-04-08 14:23:55 +02:00
bio-integrity.c block: initialize integrity buffer to zero before writing it to media 2024-08-19 05:44:50 +02:00
bio.c block: prevent an integer overflow in bvec_try_merge_hw_page 2024-02-23 08:54:44 +01:00
blk-cgroup-rwstat.c blk-cgroup: Fix the recursive blkg rwstat 2021-03-05 11:32:15 -07:00
blk-cgroup-rwstat.h blk-cgroup: separate out blkg_rwstat under CONFIG_BLK_CGROUP_RWSTAT 2019-11-07 12:28:13 -07:00
blk-cgroup.c blk-cgroup: bypass blkcg_deactivate_policy after destroying 2023-12-20 15:17:39 +01:00
blk-core.c blk-core: use pr_warn_ratelimited() in bio_check_ro() 2023-11-20 11:08:29 +01:00
blk-crypto-fallback.c block: rename BIO_MAX_PAGES to BIO_MAX_VECS 2021-03-11 07:47:48 -07:00
blk-crypto-internal.h blk-mq: release crypto keyslot before reporting I/O complete 2023-05-11 23:00:16 +09:00
blk-crypto.c blk-crypto: make blk_crypto_evict_key() more robust 2023-05-11 23:00:16 +09:00
blk-exec.c block: return errors from blk_execute_rq() 2021-06-30 15:35:45 -06:00
blk-flush.c block: Fix fsync always failed if once failed 2022-01-27 11:05:25 +01:00
blk-integrity.c blk-integrity: register sysfs attributes on struct device 2024-10-17 15:11:33 +02:00
blk-ioc.c block: fix default IO priority handling again 2022-08-11 13:07:50 +02:00
blk-iocost.c blk-iocost: Avoid using clamp() on inuse in __propagate_weights() 2024-12-19 18:07:21 +01:00
blk-iolatency.c block: don't allow the same type rq_qos add more than once 2022-08-17 14:24:24 +02:00
blk-ioprio.c block: Introduce the ioprio rq-qos policy 2021-06-21 15:03:40 -06:00
blk-ioprio.h block: Introduce the ioprio rq-qos policy 2021-06-21 15:03:40 -06:00
blk-lib.c block: export blk_next_bio() 2021-06-17 15:51:20 +02:00
blk-map.c block-map: add __GFP_ZERO flag for alloc_page in function bio_copy_kern 2022-03-08 19:12:31 +01:00
blk-merge.c blk-mq: release crypto keyslot before reporting I/O complete 2023-05-11 23:00:16 +09:00
blk-mq-cpumap.c blk-mq: remove the calling of local_memory_node() 2020-10-20 07:08:17 -06:00
blk-mq-debugfs-zoned.c block: Cleanup license notice 2019-01-17 21:21:40 -07:00
blk-mq-debugfs.c blk-mq: don't create hctx debugfs dir until q->debugfs_dir is created 2022-08-17 14:23:12 +02:00
blk-mq-debugfs.h blk-mq: no need to check return value of debugfs_create functions 2019-06-13 03:00:30 -06:00
blk-mq-pci.c block: Fix blk_mq_*_map_queues() kernel-doc headers 2019-05-31 15:12:34 -06:00
blk-mq-rdma.c block: Fix blk_mq_*_map_queues() kernel-doc headers 2019-05-31 15:12:34 -06:00
blk-mq-sched.c blk-mq: correct stale comment of .get_budget 2023-03-10 09:39:04 +01:00
blk-mq-sched.h blk: Fix lock inversion between ioc lock and bfqd lock 2021-06-24 18:43:55 -06:00
blk-mq-sysfs.c blk-mq: fix possible memleak when register 'hctx' failed 2022-12-31 13:14:43 +01:00
blk-mq-tag.c blk-mq: avoid to iterate over stale request 2021-09-12 19:32:43 -06:00
blk-mq-tag.h blk-mq: Some tag allocation code refactoring 2021-05-24 06:47:22 -06:00
blk-mq-virtio.c blk-mq: Fix typo in comment 2020-03-17 20:55:21 +01:00
blk-mq.c block: fix ordering between checking BLK_MQ_S_STOPPED request adding 2024-12-14 19:51:17 +01:00
blk-mq.h block: fix ordering between checking BLK_MQ_S_STOPPED request adding 2024-12-14 19:51:17 +01:00
blk-pm.c scsi: block: pm: Always set request queue runtime active in blk_post_runtime_resume() 2022-01-27 11:04:15 +01:00
blk-pm.h block: Remove unused blk_pm_*() function definitions 2021-02-22 06:33:48 -07:00
blk-rq-qos.c blk-rq-qos: fix crash on rq_qos_wait vs. rq_qos_wake_function race 2024-10-22 15:40:43 +02:00
blk-rq-qos.h block: don't allow the same type rq_qos add more than once 2022-08-17 14:24:24 +02:00
blk-settings.c block: Clear zone limits for a non-zoned stacked queue 2024-04-10 16:18:35 +02:00
blk-stat.c block: prevent division by zero in blk_rq_stat_sum() 2024-04-13 13:01:45 +02:00
blk-stat.h block: deactivate blk_stat timer in wbt_disable_default() 2018-12-12 06:47:51 -07:00
blk-sysfs.c block: fix use-after-free of q->q_usage_counter 2023-10-10 21:59:05 +02:00
blk-throttle.c blk-throttle: fix lockdep warning of "cgroup_mutex or RCU read lock required!" 2023-12-20 15:17:39 +01:00
blk-timeout.c block: blk-timeout: delete duplicated word 2020-07-31 16:29:47 -06:00
blk-wbt.c blk-wbt: fix that 'rwb->wc' is always set to 1 in wbt_init() 2022-10-26 12:35:54 +02:00
blk-wbt.h blk-wbt: introduce a new disable state to prevent false positive by rwb_enabled() 2021-06-21 15:03:41 -06:00
blk-zoned.c block: Hold invalidate_lock in BLKRESETZONE ioctl 2021-11-18 19:17:15 +01:00
blk.h blk-integrity: register sysfs attributes on struct device 2024-10-17 15:11:33 +02:00
bounce.c block: use memcpy_from_bvec in __blk_queue_bounce 2021-08-02 13:37:28 -06:00
bsg-lib.c scsi: bsg-lib: Fix commands without data transfer in bsg_transport_sg_io_fn() 2021-08-01 13:21:40 -04:00
bsg.c scsi: bsg: Fix device unregistration 2021-09-14 00:22:15 -04:00
disk-events.c block: increment diskseq on all media change events 2023-07-23 13:47:20 +02:00
elevator.c block: Fix elevator_get_default() checking for NULL q->tag_set 2024-11-17 15:06:24 +01:00
fops.c block: Don't invalidate pagecache for invalid falloc modes 2024-01-15 18:51:07 +01:00
genhd.c blk-integrity: register sysfs attributes on struct device 2024-10-17 15:11:33 +02:00
holder.c block: drop unused includes in <linux/genhd.h> 2022-03-16 14:23:46 +01:00
ioctl.c block/ioctl: prefer different overflow check 2024-07-05 09:14:25 +02:00
ioprio.c block: fix default IO priority handling again 2022-08-11 13:07:50 +02:00
Kconfig SCSI misc on 20210902 2021-09-02 15:09:46 -07:00
Kconfig.iosched Revert "block/mq-deadline: Add cgroup support" 2021-08-11 13:47:26 -06:00
keyslot-manager.c blk-crypto: make blk_crypto_evict_key() more robust 2023-05-11 23:00:16 +09:00
kyber-iosched.c kyber: avoid q->disk dereferences in trace points 2021-10-15 21:02:57 -06:00
Makefile block: move CONFIG_BLOCK guard to top Makefile 2022-12-14 11:37:30 +01:00
mq-deadline.c block: mq-deadline: Rename deadline_is_seq_writes() 2023-01-24 07:22:49 +01:00
opal_proto.h block: sed-opal: handle empty atoms when parsing response 2024-03-26 18:21:13 -04:00
sed-opal.c block: sed-opal: handle empty atoms when parsing response 2024-03-26 18:21:13 -04:00
t10-pi.c block: use bvec_kmap_local in t10_pi_type1_{prepare,complete} 2021-08-02 13:37:28 -06:00