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KASAN: use-after-free Read in jfs_syncpt

Status: upstream: reported C repro on 2024/04/12 18:15
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+ef99cf250087631e7fb1@syzkaller.appspotmail.com
First crash: 446d, last: 20h01m
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2024/05/15 upstream (ToT) 1b294a1f3561 C [report] KASAN: slab-use-after-free Read in jfs_syncpt
▶ ▼ Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 KASAN: use-after-free Read in jfs_syncpt origin:upstream C 109 2d20h 505d 0/3 upstream: reported C repro on 2024/02/13 19:07
upstream KASAN: slab-use-after-free Read in jfs_syncpt jfs C inconclusive 946 1d10h 511d 0/29 upstream: reported C repro on 2024/02/07 09:29
linux-6.6 KASAN: slab-use-after-free Read in jfs_syncpt origin:upstream C 3 5d15h 11d 0/2 upstream: reported C repro on 2025/06/21 09:40

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in __mutex_waiter_is_first kernel/locking/mutex.c:197 [inline]
BUG: KASAN: use-after-free in __mutex_lock_common+0xae8/0x1f38 kernel/locking/mutex.c:681
Read of size 8 at addr ffff0000c8b7c108 by task jfsCommit/93

CPU: 0 PID: 93 Comm: jfsCommit Not tainted 6.1.140-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call trace:
 dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack+0x30/0x40 lib/dump_stack.c:88
 dump_stack_lvl+0xf8/0x160 lib/dump_stack.c:106
 print_address_description+0x88/0x220 mm/kasan/report.c:316
 print_report+0x50/0x68 mm/kasan/report.c:427
 kasan_report+0xa8/0x100 mm/kasan/report.c:531
 __asan_report_load8_noabort+0x2c/0x38 mm/kasan/report_generic.c:351
 __mutex_waiter_is_first kernel/locking/mutex.c:197 [inline]
 __mutex_lock_common+0xae8/0x1f38 kernel/locking/mutex.c:681
 __mutex_lock kernel/locking/mutex.c:747 [inline]
 mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799
 jfs_syncpt+0x2c/0x94 fs/jfs/jfs_logmgr.c:1039
 txEnd+0x290/0x4f0 fs/jfs/jfs_txnmgr.c:549
 txLazyCommit fs/jfs/jfs_txnmgr.c:2684 [inline]
 jfs_lazycommit+0x498/0x918 fs/jfs/jfs_txnmgr.c:2732
 kthread+0x250/0x2d8 kernel/kthread.c:376
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:864

Allocated by task 4355:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4c/0x80 mm/kasan/common.c:52
 kasan_save_alloc_info+0x28/0x34 mm/kasan/generic.c:505
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0xa0/0xb8 mm/kasan/common.c:383
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 kmalloc_trace+0x7c/0x94 mm/slab_common.c:1031
 kmalloc include/linux/slab.h:563 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 open_inline_log fs/jfs/jfs_logmgr.c:1159 [inline]
 lmLogOpen+0x288/0xd58 fs/jfs/jfs_logmgr.c:1069
 jfs_mount_rw+0xe4/0x50c fs/jfs/jfs_mount.c:253
 jfs_fill_super+0x484/0x948 fs/jfs/super.c:565
 mount_bdev+0x264/0x358 fs/super.c:1443
 jfs_do_mount+0x44/0x58 fs/jfs/super.c:670
 legacy_get_tree+0xd4/0x16c fs/fs_context.c:632
 vfs_get_tree+0x90/0x274 fs/super.c:1573
 do_new_mount+0x228/0x810 fs/namespace.c:3058
 path_mount+0x5b4/0xe78 fs/namespace.c:3388
 do_mount fs/namespace.c:3401 [inline]
 __do_sys_mount fs/namespace.c:3609 [inline]
 __se_sys_mount fs/namespace.c:3586 [inline]
 __arm64_sys_mount+0x49c/0x584 fs/namespace.c:3586
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

Freed by task 4295:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4c/0x80 mm/kasan/common.c:52
 kasan_save_free_info+0x3c/0x60 mm/kasan/generic.c:516
 ____kasan_slab_free+0x148/0x1b0 mm/kasan/common.c:236
 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:244
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1724 [inline]
 slab_free_freelist_hook+0x16c/0x1ec mm/slub.c:1750
 slab_free mm/slub.c:3661 [inline]
 __kmem_cache_free+0xc0/0x224 mm/slub.c:3674
 kfree+0xd0/0x1ac mm/slab_common.c:988
 lmLogClose+0x250/0x4c8 fs/jfs/jfs_logmgr.c:-1
 jfs_umount+0x244/0x328 fs/jfs/jfs_umount.c:116
 jfs_put_super+0x90/0x188 fs/jfs/super.c:194
 generic_shutdown_super+0x130/0x324 fs/super.c:501
 kill_block_super+0x70/0xdc fs/super.c:1470
 deactivate_locked_super+0xac/0x124 fs/super.c:332
 deactivate_super+0xe8/0x108 fs/super.c:363
 cleanup_mnt+0x37c/0x404 fs/namespace.c:1186
 __cleanup_mnt+0x20/0x30 fs/namespace.c:1193
 task_work_run+0x1ec/0x270 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 do_notify_resume+0x1f70/0x2b0c arch/arm64/kernel/signal.c:1137
 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline]
 el0_svc+0x98/0x138 arch/arm64/kernel/entry-common.c:638
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

The buggy address belongs to the object at ffff0000c8b7c000
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 264 bytes inside of
 1024-byte region [ffff0000c8b7c000, ffff0000c8b7c400)

The buggy address belongs to the physical page:
page:00000000721edd3a refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x108b78
head:00000000721edd3a order:3 compound_mapcount:0 compound_pincount:0
flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000010200 0000000000000000 dead000000000122 ffff0000c0002780
raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000c8b7c000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff0000c8b7c080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff0000c8b7c100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff0000c8b7c180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff0000c8b7c200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
Unable to handle kernel paging request at virtual address dfff800000000006
KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]
Mem abort info:
  ESR = 0x0000000096000006
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x06: level 2 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000006
  CM = 0, WnR = 0
[dfff800000000006] address between user and kernel address ranges
Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 93 Comm: jfsCommit Tainted: G    B              6.1.140-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
pstate: 00400005 (nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : write_special_inodes fs/jfs/jfs_logmgr.c:207 [inline]
pc : lmLogSync+0xf8/0x894 fs/jfs/jfs_logmgr.c:935
lr : write_special_inodes fs/jfs/jfs_logmgr.c:207 [inline]
lr : lmLogSync+0xec/0x894 fs/jfs/jfs_logmgr.c:935
sp : ffff80001dfb7b60
x29: ffff80001dfb7c30 x28: 1ffff00003fa0822 x27: dfff800000000000
x26: 1ffff00002ac4d58 x25: dfff800000000000 x24: ffff80001dfb7b80
x23: 0000000000000002 x22: ffff700003bf6f70 x21: 0000000000000030
x20: ffff0000c920e0f8 x19: ffff0000c8b7c000 x18: ffff800011a7bd00
x17: 1fffe00033ee2f76 x16: ffff800008042940 x15: ffff80001506d000
x14: 0000000000000100 x13: 0000000000000120 x12: 0000000000ff0100
x11: ff00800009890838 x10: 0000000000000000 x9 : ffff80001c2cd9d0
x8 : 0000000000000006 x7 : 0000000000000000 x6 : ffff8000082516f8
x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff800009890884
x2 : 0000000000000000 x1 : 0000000000000008 x0 : 0000000000000000
Call trace:
 write_special_inodes fs/jfs/jfs_logmgr.c:207 [inline]
 lmLogSync+0xf8/0x894 fs/jfs/jfs_logmgr.c:935
 jfs_syncpt+0x70/0x94 fs/jfs/jfs_logmgr.c:1041
 txEnd+0x290/0x4f0 fs/jfs/jfs_txnmgr.c:549
 txLazyCommit fs/jfs/jfs_txnmgr.c:2684 [inline]
 jfs_lazycommit+0x498/0x918 fs/jfs/jfs_txnmgr.c:2732
 kthread+0x250/0x2d8 kernel/kthread.c:376
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:864
Code: 97c11520 f94002a8 9100c115 d343fea8 (387b6908) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	97c11520 	bl	0xffffffffff045480
   4:	f94002a8 	ldr	x8, [x21]
   8:	9100c115 	add	x21, x8, #0x30
   c:	d343fea8 	lsr	x8, x21, #3
* 10:	387b6908 	ldrb	w8, [x8, x27] <-- trapping instruction

Crashes (122):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/25 04:47 linux-6.1.y da3c5173c55f ed351ea7 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in jfs_syncpt
2025/04/29 13:00 linux-6.1.y 535ec20c5027 aeb6ec69 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in jfs_syncpt
2025/04/23 16:31 linux-6.1.y 420102835862 53a8b9bd .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in jfs_syncpt
2025/01/13 08:15 linux-6.1.y c63962be84ef 6dbc6a9b .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in jfs_syncpt
2024/05/15 04:14 linux-6.1.y 909ba1f1b414 fdb4c10c .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in jfs_syncpt
2025/07/01 05:08 linux-6.1.y 7e69c33e4858 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/06/27 14:18 linux-6.1.y 7e69c33e4858 803ce19b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/06/27 12:46 linux-6.1.y 7e69c33e4858 803ce19b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/06/26 18:24 linux-6.1.y 58485ff1a74f 803ce19b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/06/02 11:12 linux-6.1.y da3c5173c55f b396b4bf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/05/26 15:52 linux-6.1.y da3c5173c55f 874a1386 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/05/22 04:10 linux-6.1.y 325285d9fc86 0919b50b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/05/15 16:47 linux-6.1.y 02b72ccb5f9d cfde8269 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/05/09 09:53 linux-6.1.y 02b72ccb5f9d bb813bcc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/04/28 10:55 linux-6.1.y 535ec20c5027 c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/04/26 21:39 linux-6.1.y 535ec20c5027 c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/04/26 13:55 linux-6.1.y 535ec20c5027 c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/04/26 02:29 linux-6.1.y 535ec20c5027 c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/04/24 01:36 linux-6.1.y 420102835862 73a168d0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/04/23 23:56 linux-6.1.y 420102835862 73a168d0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/04/22 09:36 linux-6.1.y 420102835862 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/04/22 08:21 linux-6.1.y 420102835862 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/04/21 20:30 linux-6.1.y 420102835862 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/04/04 18:38 linux-6.1.y 8e60a714ba3b 1c4febdb .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/04/01 20:17 linux-6.1.y 8e60a714ba3b b8645499 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/04/01 15:02 linux-6.1.y 8e60a714ba3b b8645499 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/03/23 04:30 linux-6.1.y 344a09659766 4e8d3850 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/03/12 09:15 linux-6.1.y 6ae7ac5c4251 ee70e6db .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/03/09 02:07 linux-6.1.y 6ae7ac5c4251 163f510d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/02/18 09:52 linux-6.1.y 0cbb5f65e52f c37c7249 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/02/17 10:14 linux-6.1.y 0cbb5f65e52f 4121cf9d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/02/11 16:42 linux-6.1.y 0cbb5f65e52f f2baddf5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/02/09 18:34 linux-6.1.y 0cbb5f65e52f ef44b750 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/01/29 14:47 linux-6.1.y 75cefdf153f5 136953f1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/01/26 14:04 linux-6.1.y 75cefdf153f5 9fbd772e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/01/15 19:25 linux-6.1.y c63962be84ef 968edaf4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/01/13 11:55 linux-6.1.y c63962be84ef 249ceea9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/01/08 20:36 linux-6.1.y 7dc732d24ff7 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2024/12/22 03:28 linux-6.1.y 29f02ec58a94 d7f584ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2024/11/27 19:14 linux-6.1.y e4d90d63d385 5df23865 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2024/11/27 12:01 linux-6.1.y e4d90d63d385 52b38cc1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2024/04/12 18:15 linux-6.1.y bf1e3b1cb1e0 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in jfs_syncpt
2025/07/02 08:17 linux-6.1.y 7e69c33e4858 bc80e4f0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in jfs_syncpt
2025/06/27 09:54 linux-6.1.y 58485ff1a74f 803ce19b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in jfs_syncpt
2025/06/03 04:12 linux-6.1.y da3c5173c55f a30356b7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in jfs_syncpt
2025/03/26 18:37 linux-6.1.y 344a09659766 20510e88 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in jfs_syncpt
2025/03/16 13:31 linux-6.1.y 344a09659766 e2826670 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in jfs_syncpt
2025/02/28 16:56 linux-6.1.y 3a8358583626 67cf5345 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in jfs_syncpt
2025/02/08 20:27 linux-6.1.y 0cbb5f65e52f ef44b750 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in jfs_syncpt
2024/11/27 22:03 linux-6.1.y e4d90d63d385 5df23865 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in jfs_syncpt
* Struck through repros no longer work on HEAD.