syzbot


KASAN: slab-use-after-free Read in list_lru_del

Status: upstream: reported syz repro on 2025/02/06 17:01
Subsystems: mm
[Documentation on labels]
Reported-by: syzbot+6663075ddb9be85fa6e5@syzkaller.appspotmail.com
First crash: 263d, last: 5d17h
Cause bisection: introduced by (bisect log) :
commit 14152654805256d760315ec24e414363bfa19a06
Author: Kent Overstreet <kent.overstreet@linux.dev>
Date: Mon Nov 25 05:21:27 2024 +0000

  bcachefs: Bad btree roots are now autofix

Crash: invalid opcode in corrupted (log)
Repro: syz .config
  
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [mm?] [bcachefs?] KASAN: slab-use-after-free Read in list_lru_del 0 (2) 2025/03/07 22:42
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream BUG: corrupted list in list_lru_del mm 8 2 1047d 1086d 0/29 auto-obsoleted due to no activity on 2023/03/15 19:34
Last patch testing requests (3)
Created Duration User Patch Repo Result
2025/03/16 02:44 1h11m retest repro upstream OK log
2025/03/16 02:44 19m retest repro upstream OK log
2025/03/15 18:54 21m retest repro upstream OK log

Sample crash report:
loop0: detected capacity change from 0 to 32768
gfs2: fsid=syz:syz: Trying to join cluster "lock_nolock", "syz:syz"
gfs2: fsid=syz:syz: Now mounting FS (format 1801)...
gfs2: fsid=syz:syz.0: journal 0 mapped with 3 extents in 0ms
gfs2: fsid=syz:syz.0: first mount done, others may mount
gfs2: fsid=syz:syz.0: found 1 quota changes
loop0: detected capacity change from 32768 to 0
==================================================================
BUG: KASAN: slab-use-after-free in __list_del_entry_valid_or_report+0xb5/0x190 lib/list_debug.c:65
Read of size 8 at addr ffff88804bd99080 by task syz.0.0/5330

CPU: 0 UID: 0 PID: 5330 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) 
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_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xca/0x240 mm/kasan/report.c:482
 kasan_report+0x118/0x150 mm/kasan/report.c:595
 __list_del_entry_valid_or_report+0xb5/0x190 lib/list_debug.c:65
 __list_del_entry_valid include/linux/list.h:132 [inline]
 __list_del_entry include/linux/list.h:223 [inline]
 list_del_init include/linux/list.h:295 [inline]
 list_lru_del+0x98/0x210 mm/list_lru.c:210
 gfs2_quota_cleanup+0x21e/0x6f0 fs/gfs2/quota.c:1532
 gfs2_make_fs_ro+0x27a/0x300 fs/gfs2/super.c:566
 gfs2_put_super+0x224/0x950 fs/gfs2/super.c:598
 generic_shutdown_super+0x135/0x2c0 fs/super.c:642
 kill_block_super+0x44/0x90 fs/super.c:1722
 deactivate_locked_super+0xbc/0x130 fs/super.c:473
 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1327
 task_work_run+0x1d4/0x260 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x6b5/0x2300 kernel/exit.c:966
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1107
 get_signal+0x1285/0x1340 kernel/signal.c:3034
 arch_do_signal_or_restart+0xa0/0x790 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x72/0x130 kernel/entry/common.c:40
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6b0638efc9
Code: Unable to access opcode bytes at 0x7f6b0638ef9f.
RSP: 002b:00007f6b072240e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f6b065e5fa8 RCX: 00007f6b0638efc9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f6b065e5fa8
RBP: 00007f6b065e5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6b065e6038 R14: 00007ffcf3e72630 R15: 00007ffcf3e72718
 </TASK>

Allocated by task 5330:
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
 unpoison_slab_object mm/kasan/common.c:342 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:368
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4962 [inline]
 slab_alloc_node mm/slub.c:5272 [inline]
 kmem_cache_alloc_noprof+0x367/0x6e0 mm/slub.c:5279
 qd_alloc+0x50/0x250 fs/gfs2/quota.c:234
 gfs2_quota_init+0x762/0x1200 fs/gfs2/quota.c:1448
 gfs2_make_fs_rw+0x181/0x2b0 fs/gfs2/super.c:149
 gfs2_fill_super+0x1a7b/0x20d0 fs/gfs2/ops_fstype.c:1280
 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1691
 gfs2_get_tree+0x51/0x1e0 fs/gfs2/ops_fstype.c:1337
 vfs_get_tree+0x92/0x2b0 fs/super.c:1751
 fc_mount fs/namespace.c:1208 [inline]
 do_new_mount_fc fs/namespace.c:3651 [inline]
 do_new_mount+0x302/0xa10 fs/namespace.c:3727
 do_mount fs/namespace.c:4050 [inline]
 __do_sys_mount fs/namespace.c:4238 [inline]
 __se_sys_mount+0x313/0x410 fs/namespace.c:4215
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 15:
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
 __kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:587
 kasan_save_free_info mm/kasan/kasan.h:406 [inline]
 poison_slab_object mm/kasan/common.c:252 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284
 kasan_slab_free include/linux/kasan.h:234 [inline]
 slab_free_hook mm/slub.c:2530 [inline]
 slab_free mm/slub.c:6619 [inline]
 kmem_cache_free+0x19b/0x690 mm/slub.c:6729
 gfs2_qd_dealloc+0x70/0xe0 fs/gfs2/quota.c:111
 rcu_do_batch kernel/rcu/tree.c:2605 [inline]
 rcu_core+0xcab/0x1770 kernel/rcu/tree.c:2861
 handle_softirqs+0x286/0x870 kernel/softirq.c:622
 run_ksoftirqd+0x9b/0x100 kernel/softirq.c:1063
 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Last potentially related work creation:
 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:56
 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:559
 __call_rcu_common kernel/rcu/tree.c:3123 [inline]
 call_rcu+0x157/0x9c0 kernel/rcu/tree.c:3243
 gfs2_quota_sync+0x3c4/0x460 fs/gfs2/quota.c:1361
 gfs2_sync_fs+0x4c/0xb0 fs/gfs2/super.c:658
 __iterate_supers+0x13d/0x290 fs/super.c:923
 ksys_sync+0xb2/0x150 fs/sync.c:104
 __ia32_sys_sync+0xe/0x20 fs/sync.c:113
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88804bd99000
 which belongs to the cache gfs2_quotad of size 272
The buggy address is located 128 bytes inside of
 freed 272-byte region [ffff88804bd99000, ffff88804bd99110)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4bd99
flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 04fff00000000000 ffff88801fc00b40 dead000000000122 0000000000000000
raw: 0000000000000000 00000000800c000c 00000000f5000000 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Reclaimable, gfp_mask 0x52c50(GFP_NOFS|__GFP_RECLAIMABLE|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 5330, tgid 5329 (syz.0.0), ts 86019510290, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1850
 prep_new_page mm/page_alloc.c:1858 [inline]
 get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3884
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5183
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416
 alloc_slab_page mm/slub.c:3046 [inline]
 allocate_slab+0x96/0x3a0 mm/slub.c:3219
 new_slab mm/slub.c:3273 [inline]
 ___slab_alloc+0xe94/0x18a0 mm/slub.c:4643
 __slab_alloc+0x65/0x100 mm/slub.c:4762
 __slab_alloc_node mm/slub.c:4838 [inline]
 slab_alloc_node mm/slub.c:5260 [inline]
 kmem_cache_alloc_noprof+0x3f9/0x6e0 mm/slub.c:5279
 qd_alloc+0x50/0x250 fs/gfs2/quota.c:234
 gfs2_quota_init+0x762/0x1200 fs/gfs2/quota.c:1448
 gfs2_make_fs_rw+0x181/0x2b0 fs/gfs2/super.c:149
 gfs2_fill_super+0x1a7b/0x20d0 fs/gfs2/ops_fstype.c:1280
 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1691
 gfs2_get_tree+0x51/0x1e0 fs/gfs2/ops_fstype.c:1337
 vfs_get_tree+0x92/0x2b0 fs/super.c:1751
 fc_mount fs/namespace.c:1208 [inline]
 do_new_mount_fc fs/namespace.c:3651 [inline]
 do_new_mount+0x302/0xa10 fs/namespace.c:3727
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88804bd98f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88804bd99000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88804bd99080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff88804bd99100: fb fb fc fc fc fc fc fc fc fc 00 00 00 00 00 00
 ffff88804bd99180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================

Crashes (24):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/22 04:32 upstream 6548d364a3e8 252fbbad .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-use-after-free Read in list_lru_del
2025/10/20 19:34 upstream 211ddde0823f d422939c .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-use-after-free Read in list_lru_del
2025/10/04 06:48 upstream 2ccb4d203fe4 49379ee0 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-use-after-free Read in list_lru_del
2025/09/14 19:30 upstream f83a4f2a4d8c e2beed91 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-use-after-free Read in list_lru_del
2025/08/17 20:33 upstream 99bade344cfa dcc075fb .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-use-after-free Read in list_lru_del
2025/08/16 01:30 upstream 8d084337a32f dcc075fb .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-use-after-free Read in list_lru_del
2025/08/15 14:18 upstream 24ea63ea3877 dcc075fb .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-use-after-free Read in list_lru_del
2025/07/16 23:52 upstream 155a3c003e55 44f8051e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-use-after-free Read in list_lru_del
2025/07/02 22:02 upstream b4911fb0b060 0cd59a8f .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-use-after-free Read in list_lru_del
2025/06/27 18:06 upstream 67a993863163 803ce19b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-use-after-free Read in list_lru_del
2025/06/25 16:05 upstream 7595b66ae9de 26d77996 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-use-after-free Read in list_lru_del
2025/05/31 06:36 upstream 8477ab143069 3d2f584d .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-use-after-free Read in list_lru_del
2025/05/29 16:38 upstream 90b83efa6701 3d2f584d .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-use-after-free Read in list_lru_del
2025/05/21 21:38 upstream 4a95bc121ccd f6063999 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-use-after-free Read in list_lru_del
2025/05/05 18:20 upstream 92a09c47464d 6ca47dd8 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-use-after-free Read in list_lru_del
2025/04/25 07:20 upstream e72e9e693307 e3715315 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-use-after-free Read in list_lru_del
2025/04/06 07:03 upstream 56f944529ec2 1c65791e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-use-after-free Read in list_lru_del
2025/04/01 18:47 upstream 08733088b566 b8645499 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-use-after-free Read in list_lru_del
2025/03/21 21:27 upstream d07de43e3f05 c6512ef7 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-use-after-free Read in list_lru_del
2025/02/20 22:50 upstream e9a8cac0bf89 0808a665 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-use-after-free Read in list_lru_del
2025/02/06 06:31 upstream 92514ef226f5 577d049b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-use-after-free Read in list_lru_del
2025/03/01 18:44 upstream 03d38806a902 c3901742 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-upstream-fs BUG: corrupted list in list_lru_del
2025/02/19 02:47 upstream 6537cfb395f3 9a14138f .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-upstream-fs BUG: corrupted list in list_lru_del
2025/02/06 13:59 upstream 92514ef226f5 1e1faf27 .config console log report syz / log [disk image (non-bootable)] [vmlinux] [kernel image] [mounted in repro] ci-snapshot-upstream-root BUG: corrupted list in list_lru_del
* Struck through repros no longer work on HEAD.