Re: [syzbot] [mm?] KASAN: slab-use-after-free Read in folio_evictable (3)

syzbot
2024-12-14T00:31:03Z

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
possible deadlock in __submit_bio

Adding 124996k swap on ./swap-file. Priority:0 extents:1 across:124996k
======================================================
WARNING: possible circular locking dependency detected
6.13.0-rc2-syzkaller-00232-g4800575d8c0b-dirty #0 Not tainted
------------------------------------------------------
syz-executor/5695 is trying to acquire lock:
ffff888034c21438 (&q->q_usage_counter(io)#37){++++}-{0:0}, at: __submit_bio+0x2c6/0x560 block/blk-core.c:629

but task is already holding lock:
ffffffff8ea35ca0 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:3924 [inline]
ffffffff8ea35ca0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim+0xd4/0x3c0 mm/page_alloc.c:3949

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (fs_reclaim){+.+.}-{0:0}:
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
__fs_reclaim_acquire mm/page_alloc.c:3851 [inline]
fs_reclaim_acquire+0x88/0x130 mm/page_alloc.c:3865
might_alloc include/linux/sched/mm.h:318 [inline]
slab_pre_alloc_hook mm/slub.c:4070 [inline]
slab_alloc_node mm/slub.c:4148 [inline]
__do_kmalloc_node mm/slub.c:4297 [inline]
__kmalloc_node_noprof+0xb2/0x4d0 mm/slub.c:4304
__kvmalloc_node_noprof+0x72/0x190 mm/util.c:650
sbitmap_init_node+0x2d4/0x670 lib/sbitmap.c:132
scsi_realloc_sdev_budget_map+0x2a7/0x460 drivers/scsi/scsi_scan.c:246
scsi_add_lun drivers/scsi/scsi_scan.c:1106 [inline]
scsi_probe_and_add_lun+0x3173/0x4bd0 drivers/scsi/scsi_scan.c:1287
__scsi_add_device+0x228/0x2f0 drivers/scsi/scsi_scan.c:1622
ata_scsi_scan_host+0x236/0x740 drivers/ata/libata-scsi.c:4575
async_run_entry_fn+0xa8/0x420 kernel/async.c:129
process_one_work kernel/workqueue.c:3229 [inline]
process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310
worker_thread+0x870/0xd30 kernel/workqueue.c:3391
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

-> #0 (&q->q_usage_counter(io)#37){++++}-{0:0}:
check_prev_add kernel/locking/lockdep.c:3161 [inline]
check_prevs_add kernel/locking/lockdep.c:3280 [inline]
validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
__lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
bio_queue_enter block/blk.h:75 [inline]
blk_mq_submit_bio+0x1536/0x2390 block/blk-mq.c:3092
__submit_bio+0x2c6/0x560 block/blk-core.c:629
__submit_bio_noacct_mq block/blk-core.c:710 [inline]
submit_bio_noacct_nocheck+0x4d3/0xe30 block/blk-core.c:739
swap_writepage_bdev_async mm/page_io.c:451 [inline]
__swap_writepage+0x747/0x14d0 mm/page_io.c:474
swap_writepage+0x6ee/0xce0 mm/page_io.c:289
pageout mm/vmscan.c:689 [inline]
shrink_folio_list+0x3b68/0x5ca0 mm/vmscan.c:1367
evict_folios+0x3c86/0x5800 mm/vmscan.c:4593
try_to_shrink_lruvec+0x9a6/0xc70 mm/vmscan.c:4789
shrink_one+0x3b9/0x850 mm/vmscan.c:4834
shrink_many mm/vmscan.c:4897 [inline]
lru_gen_shrink_node mm/vmscan.c:4975 [inline]
shrink_node+0x37c5/0x3e50 mm/vmscan.c:5956
shrink_zones mm/vmscan.c:6215 [inline]
do_try_to_free_pages+0x78c/0x1cf0 mm/vmscan.c:6277
try_to_free_pages+0x47c/0x1050 mm/vmscan.c:6527
__perform_reclaim mm/page_alloc.c:3927 [inline]
__alloc_pages_direct_reclaim+0x178/0x3c0 mm/page_alloc.c:3949
__alloc_pages_slowpath+0x764/0x1020 mm/page_alloc.c:4380
__alloc_pages_noprof+0x49b/0x710 mm/page_alloc.c:4764
alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2269
folio_alloc_mpol_noprof mm/mempolicy.c:2287 [inline]
vma_alloc_folio_noprof+0x12e/0x230 mm/mempolicy.c:2317
folio_prealloc+0x2e/0x170
alloc_anon_folio mm/memory.c:4752 [inline]
do_anonymous_page mm/memory.c:4809 [inline]
do_pte_missing mm/memory.c:3977 [inline]
handle_pte_fault+0x2c98/0x5ed0 mm/memory.c:5801
__handle_mm_fault mm/memory.c:5944 [inline]
handle_mm_fault+0x1106/0x1bb0 mm/memory.c:6112
do_user_addr_fault arch/x86/mm/fault.c:1338 [inline]
handle_page_fault arch/x86/mm/fault.c:1481 [inline]
exc_page_fault+0x459/0x8b0 arch/x86/mm/fault.c:1539
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

other info that might help us debug this:

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(fs_reclaim);
lock(&q->q_usage_counter(io)#37);
lock(fs_reclaim);
rlock(&q->q_usage_counter(io)#37);

*** DEADLOCK ***

2 locks held by syz-executor/5695:
#0: ffff888011d6c8e0 (&vma->vm_lock->lock){++++}-{4:4}, at: vma_start_read include/linux/mm.h:716 [inline]
#0: ffff888011d6c8e0 (&vma->vm_lock->lock){++++}-{4:4}, at: lock_vma_under_rcu+0x34b/0x790 mm/memory.c:6278
#1: ffffffff8ea35ca0 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:3924 [inline]
#1: ffffffff8ea35ca0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim+0xd4/0x3c0 mm/page_alloc.c:3949

stack backtrace:
CPU: 0 UID: 0 PID: 5695 Comm: syz-executor Not tainted 6.13.0-rc2-syzkaller-00232-g4800575d8c0b-dirty #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074
check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206
check_prev_add kernel/locking/lockdep.c:3161 [inline]
check_prevs_add kernel/locking/lockdep.c:3280 [inline]
validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
__lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
bio_queue_enter block/blk.h:75 [inline]
blk_mq_submit_bio+0x1536/0x2390 block/blk-mq.c:3092
__submit_bio+0x2c6/0x560 block/blk-core.c:629
__submit_bio_noacct_mq block/blk-core.c:710 [inline]
submit_bio_noacct_nocheck+0x4d3/0xe30 block/blk-core.c:739
swap_writepage_bdev_async mm/page_io.c:451 [inline]
__swap_writepage+0x747/0x14d0 mm/page_io.c:474
swap_writepage+0x6ee/0xce0 mm/page_io.c:289
pageout mm/vmscan.c:689 [inline]
shrink_folio_list+0x3b68/0x5ca0 mm/vmscan.c:1367
evict_folios+0x3c86/0x5800 mm/vmscan.c:4593
try_to_shrink_lruvec+0x9a6/0xc70 mm/vmscan.c:4789
shrink_one+0x3b9/0x850 mm/vmscan.c:4834
shrink_many mm/vmscan.c:4897 [inline]
lru_gen_shrink_node mm/vmscan.c:4975 [inline]
shrink_node+0x37c5/0x3e50 mm/vmscan.c:5956
shrink_zones mm/vmscan.c:6215 [inline]
do_try_to_free_pages+0x78c/0x1cf0 mm/vmscan.c:6277
try_to_free_pages+0x47c/0x1050 mm/vmscan.c:6527
__perform_reclaim mm/page_alloc.c:3927 [inline]
__alloc_pages_direct_reclaim+0x178/0x3c0 mm/page_alloc.c:3949
__alloc_pages_slowpath+0x764/0x1020 mm/page_alloc.c:4380
__alloc_pages_noprof+0x49b/0x710 mm/page_alloc.c:4764
alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2269
folio_alloc_mpol_noprof mm/mempolicy.c:2287 [inline]
vma_alloc_folio_noprof+0x12e/0x230 mm/mempolicy.c:2317
folio_prealloc+0x2e/0x170
alloc_anon_folio mm/memory.c:4752 [inline]
do_anonymous_page mm/memory.c:4809 [inline]
do_pte_missing mm/memory.c:3977 [inline]
handle_pte_fault+0x2c98/0x5ed0 mm/memory.c:5801
__handle_mm_fault mm/memory.c:5944 [inline]
handle_mm_fault+0x1106/0x1bb0 mm/memory.c:6112
do_user_addr_fault arch/x86/mm/fault.c:1338 [inline]
handle_page_fault arch/x86/mm/fault.c:1481 [inline]
exc_page_fault+0x459/0x8b0 arch/x86/mm/fault.c:1539
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7fd75394f603
Code: 07 62 e1 7d 28 e7 4f 01 62 e1 7d 28 e7 57 02 62 e1 7d 28 e7 5f 03 62 e1 7d 28 e7 a7 00 10 00 00 62 e1 7d 28 e7 af 20 10 00 00 <62> e1 7d 28 e7 b7 40 10 00 00 62 e1 7d 28 e7 bf 60 10 00 00 48 83
RSP: 002b:00007fff07875f68 EFLAGS: 00010203
RAX: 00007fd74dca2aa8 RBX: 00007fff07876420 RCX: 0000000000000016
RDX: 00000000000014b0 RSI: 00007fd7520325c8 RDI: 00007fd74e170fc0
RBP: 0000000000000020 R08: ffffffffffffffe8 R09: 0000000000000000
R10: 0000000000000be6 R11: 000000000c000000 R12: 00007fd751b64010
R13: 0000000000000020 R14: 0000000000e4da98 R15: 0000000001c9b4c8
</TASK>

Tested on:

commit: 4800575d Merge tag 'xfs-fixes-6.13-rc3' of git://git.k..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13983be8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=fee25f93665c89ac
dashboard link: https://syzkaller.appspot.com/bug?extid=4c7590f1cee06597e43a
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch: https://syzkaller.appspot.com/x/patch.diff?x=1506a4f8580000