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KASAN: use-after-free Read in jfs_lazycommit

Status: upstream: reported C repro on 2023/05/06 12:04
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+22c79e795372bfe8b681@syzkaller.appspotmail.com
First crash: 900d, last: 1d17h
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2023/10/25 upstream (ToT) 611da07b89fd C [report] KASAN: slab-use-after-free Read in jfs_lazycommit
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: use-after-free Read in jfs_lazycommit jfs 19 C error 2148 9h14m 1117d 0/29 upstream: reported C repro on 2022/10/01 13:43
linux-4.19 KASAN: use-after-free Read in jfs_lazycommit jfs 19 C error 5 988d 1105d 0/1 upstream: reported C repro on 2022/10/13 08:33
linux-6.1 KASAN: use-after-free Read in jfs_lazycommit origin:upstream missing-backport 19 C inconclusive 171 3d15h 898d 0/3 upstream: reported C repro on 2023/05/07 23:35
linux-4.14 KASAN: use-after-free Read in jfs_lazycommit jfs 19 C 6 965d 1106d 0/1 upstream: reported C repro on 2022/10/11 20:09
linux-6.6 KASAN: slab-use-after-free Read in jfs_lazycommit origin:upstream 19 C 38 4d17h 126d 0/2 upstream: reported C repro on 2025/06/18 00:01
▶ ▼ Last patch testing requests (6)
Created Duration User Patch Repo Result
2025/02/15 22:33 14m retest repro linux-5.15.y report log
2025/01/11 18:07 12m retest repro linux-5.15.y report log
2025/01/11 18:07 26m retest repro linux-5.15.y report log
2024/12/28 01:20 15m retest repro linux-5.15.y report log
2024/10/29 10:51 13m retest repro linux-5.15.y report log
2024/10/29 10:51 15m retest repro linux-5.15.y report log
▶ ▼ Fix bisection attempts (2)
Created Duration User Patch Repo Result
2023/11/13 02:23 0m bisect fix linux-5.15.y error job log
2023/10/11 15:07 1h48m bisect fix linux-5.15.y OK (0) job log log

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in jfs_lazycommit+0x763/0xb20 fs/jfs/jfs_txnmgr.c:2769
Read of size 4 at addr ffff88805a23c894 by task jfsCommit/277

CPU: 1 PID: 277 Comm: jfsCommit Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 print_address_description+0x60/0x2d0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0xdf/0x130 mm/kasan/report.c:451
 jfs_lazycommit+0x763/0xb20 fs/jfs/jfs_txnmgr.c:2769
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Allocated by task 4427:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 ____kasan_kmalloc mm/kasan/common.c:513 [inline]
 __kasan_kmalloc+0xb5/0xf0 mm/kasan/common.c:522
 kmalloc include/linux/slab.h:607 [inline]
 kzalloc include/linux/slab.h:738 [inline]
 jfs_fill_super+0xd2/0xaf0 fs/jfs/super.c:500
 mount_bdev+0x287/0x3c0 fs/super.c:1400
 legacy_get_tree+0xe6/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1530
 do_new_mount+0x24a/0xa40 fs/namespace.c:3034
 do_mount fs/namespace.c:3377 [inline]
 __do_sys_mount fs/namespace.c:3585 [inline]
 __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3562
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Freed by task 4304:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:46
 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
 ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1710 [inline]
 slab_free_freelist_hook+0xea/0x170 mm/slub.c:1736
 slab_free mm/slub.c:3504 [inline]
 kfree+0xef/0x2a0 mm/slub.c:4564
 generic_shutdown_super+0x130/0x300 fs/super.c:475
 kill_block_super+0x7c/0xe0 fs/super.c:1427
 deactivate_locked_super+0x93/0xf0 fs/super.c:335
 cleanup_mnt+0x418/0x4d0 fs/namespace.c:1148
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

The buggy address belongs to the object at ffff88805a23c800
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 148 bytes inside of
 256-byte region [ffff88805a23c800, ffff88805a23c900)
The buggy address belongs to the page:
page:ffffea0001688f00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5a23c
head:ffffea0001688f00 order:1 compound_mapcount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea0001cf6d80 0000000600000006 ffff888016841b40
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4256, ts 100419805326, free_ts 21366966125
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x1b77/0x1c60 mm/page_alloc.c:4192
 __alloc_pages+0x1e1/0x470 mm/page_alloc.c:5487
 alloc_slab_page mm/slub.c:1780 [inline]
 allocate_slab mm/slub.c:1917 [inline]
 new_slab+0xc0/0x4b0 mm/slub.c:1980
 ___slab_alloc+0x81e/0xdf0 mm/slub.c:3013
 __slab_alloc mm/slub.c:3100 [inline]
 slab_alloc_node mm/slub.c:3191 [inline]
 slab_alloc mm/slub.c:3233 [inline]
 __kmalloc_track_caller+0x1cb/0x330 mm/slub.c:4930
 kmemdup+0x22/0x50 mm/util.c:128
 mpls_net_init+0x89/0x1a0 net/mpls/af_mpls.c:2691
 ops_init+0x357/0x600 net/core/net_namespace.c:138
 setup_net+0x38d/0x9f0 net/core/net_namespace.c:333
 copy_net_ns+0x348/0x5b0 net/core/net_namespace.c:503
 create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x116/0x160 kernel/nsproxy.c:226
 ksys_unshare+0x4bc/0x890 kernel/fork.c:3175
 __do_sys_unshare kernel/fork.c:3249 [inline]
 __se_sys_unshare kernel/fork.c:3247 [inline]
 __x64_sys_unshare+0x34/0x40 kernel/fork.c:3247
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1340 [inline]
 free_pcp_prepare mm/page_alloc.c:1391 [inline]
 free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317
 free_unref_page+0x94/0x280 mm/page_alloc.c:3396
 free_contig_range+0x96/0xf0 mm/page_alloc.c:9406
 destroy_args+0x100/0xa20 mm/debug_vm_pgtable.c:1018
 debug_vm_pgtable+0x318/0x370 mm/debug_vm_pgtable.c:1336
 do_one_initcall+0x1ee/0x680 init/main.c:1316
 do_initcall_level+0x137/0x1f0 init/main.c:1389
 do_initcalls+0x4b/0x90 init/main.c:1405
 kernel_init_freeable+0x3ce/0x560 init/main.c:1629
 kernel_init+0x19/0x1b0 init/main.c:1520
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

Memory state around the buggy address:
 ffff88805a23c780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88805a23c800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88805a23c880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff88805a23c900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88805a23c980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (228):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/21 01:17 linux-5.15.y ac56c046adf4 d422939c .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/05/21 02:45 linux-5.15.y a68c15152131 b47f9e02 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2023/06/03 06:46 linux-5.15.y 0ab06468cbd1 a4ae4f42 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/05/08 18:40 linux-5.15.y 16fdf2c7111b dbf35fa1 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro #1 (corrupt fs)] [mounted in repro #2] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in jfs_lazycommit
2024/11/16 23:17 linux-5.15.y d98fd109f827 cfe3a04a .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in jfs_lazycommit
2023/05/14 03:00 linux-5.15.y b0ece631f84a 2b9ba477 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in jfs_lazycommit
2023/05/07 14:32 linux-5.15.y 8a7f2a5c5aa1 90c93c40 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in jfs_lazycommit
2025/05/21 09:20 linux-5.15.y a68c15152131 b47f9e02 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/10/18 01:50 linux-5.15.y 29e53a5b1c4f 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/10/13 14:39 linux-5.15.y 29e53a5b1c4f b6605ba8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/10/08 22:05 linux-5.15.y 29e53a5b1c4f 7e2882b3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/10/06 16:00 linux-5.15.y 29e53a5b1c4f 91305dbe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/10/04 22:53 linux-5.15.y 29e53a5b1c4f 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/09/29 03:03 linux-5.15.y 43bb85222e53 001c9061 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/09/28 09:27 linux-5.15.y 43bb85222e53 001c9061 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/09/27 08:43 linux-5.15.y 43bb85222e53 001c9061 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/09/26 22:04 linux-5.15.y 43bb85222e53 001c9061 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/09/24 13:35 linux-5.15.y 43bb85222e53 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/09/19 14:28 linux-5.15.y 43bb85222e53 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/09/17 18:53 linux-5.15.y 43bb85222e53 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/09/09 23:13 linux-5.15.y de9476bb4f1b d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/09/09 01:51 linux-5.15.y 7a6c2d093c45 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/09/05 16:50 linux-5.15.y 7a6c2d093c45 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/09/05 05:31 linux-5.15.y 7a6c2d093c45 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/09/04 06:18 linux-5.15.y 01879f56bdde d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/09/03 20:10 linux-5.15.y 01879f56bdde 96a211bc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/09/02 11:26 linux-5.15.y 01879f56bdde 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/09/02 03:47 linux-5.15.y 01879f56bdde 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/31 11:52 linux-5.15.y 01879f56bdde 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/30 04:17 linux-5.15.y 01879f56bdde 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/28 22:56 linux-5.15.y 01879f56bdde d401b9d7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/28 13:07 linux-5.15.y c79648372d02 e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/28 10:57 linux-5.15.y c79648372d02 e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/28 03:00 linux-5.15.y c79648372d02 e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/27 02:59 linux-5.15.y c79648372d02 e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/26 21:37 linux-5.15.y c79648372d02 e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/25 22:17 linux-5.15.y c79648372d02 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/24 15:16 linux-5.15.y c79648372d02 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/24 04:47 linux-5.15.y c79648372d02 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/19 06:11 linux-5.15.y c79648372d02 523f460e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/17 04:51 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/17 04:51 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/14 10:37 linux-5.15.y c79648372d02 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/12 08:53 linux-5.15.y c79648372d02 c06e8995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/11 22:18 linux-5.15.y c79648372d02 c06e8995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/11 14:00 linux-5.15.y c79648372d02 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/08 17:23 linux-5.15.y c79648372d02 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/08 03:36 linux-5.15.y c79648372d02 6a893178 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/06 00:00 linux-5.15.y c79648372d02 ffe1dd46 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/04 23:34 linux-5.15.y c79648372d02 f5bcc8dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/07/31 20:12 linux-5.15.y c79648372d02 0c075d67 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/07/23 18:48 linux-5.15.y c79648372d02 e1dd4f22 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/07/19 09:57 linux-5.15.y c79648372d02 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in jfs_lazycommit
2025/08/04 20:33 linux-5.15.y c79648372d02 f5bcc8dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in jfs_lazycommit
2025/07/26 11:12 linux-5.15.y c79648372d02 fb8f743d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in jfs_lazycommit
2023/05/06 12:03 linux-5.15.y 8a7f2a5c5aa1 90c93c40 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in jfs_lazycommit
2025/08/17 09:42 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan general protection fault in jfs_lazycommit
* Struck through repros no longer work on HEAD.