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KASAN: use-after-free Write in udf_close_lvid

Status: upstream: reported C repro on 2023/05/23 16:31
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+61564e5023b7229ec85d@syzkaller.appspotmail.com
First crash: 841d, last: 8d12h
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2023/05/23 upstream (ToT) ae8373a5add4 C [report] KASAN: use-after-free Read in crc_itu_t
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 KASAN: use-after-free Write in udf_close_lvid udf 24 C error 5 944d 1359d 0/1 upstream: reported C repro on 2021/12/21 15:22
linux-4.14 KASAN: use-after-free Write in udf_close_lvid udf 24 C 4 945d 1008d 0/1 upstream: reported C repro on 2022/12/07 21:30
linux-6.1 BUG: unable to handle kernel paging request in udf_close_lvid origin:upstream 24 C error 40 148d 893d 0/3 upstream: reported C repro on 2023/04/01 11:57
upstream KASAN: use-after-free Write in udf_close_lvid udf 24 C done 144 611d 1205d 25/29 fixed on 2024/02/21 18:23
upstream BUG: unable to handle kernel paging request in udf_close_lvid udf 8 1 312d 308d 0/29 auto-obsoleted due to no activity on 2025/01/31 11:46
▶ ▼ Last patch testing requests (10)
Created Duration User Patch Repo Result
2025/08/23 04:09 45m retest repro linux-5.15.y report log
2025/08/23 04:09 12m retest repro linux-5.15.y report log
2025/08/23 04:09 9m retest repro linux-5.15.y report log
2025/08/23 04:09 12m retest repro linux-5.15.y report log
2025/08/23 04:09 11m retest repro linux-5.15.y report log
2025/07/26 14:55 12m retest repro linux-5.15.y report log
2025/07/26 14:55 14m retest repro linux-5.15.y report log
2025/07/26 14:55 9m retest repro linux-5.15.y report log
2025/07/26 14:55 9m retest repro linux-5.15.y report log
2025/07/26 14:55 9m retest repro linux-5.15.y report log
▶ ▼ Fix bisection attempts (10)
Created Duration User Patch Repo Result
2024/10/14 23:27 0m bisect fix linux-5.15.y error job log
2024/08/30 15:54 48m bisect fix linux-5.15.y OK (0) job log log
2024/07/23 17:46 1h07m bisect fix linux-5.15.y OK (0) job log log
2024/06/08 04:00 55m bisect fix linux-5.15.y OK (0) job log log
2024/03/25 01:46 1h06m bisect fix linux-5.15.y OK (0) job log log
2024/02/23 14:18 59m bisect fix linux-5.15.y OK (0) job log log
2024/01/14 18:39 1h31m bisect fix linux-5.15.y OK (0) job log log
2023/12/10 01:52 1h16m bisect fix linux-5.15.y OK (0) job log log
2023/11/09 21:23 1h26m bisect fix linux-5.15.y OK (0) job log log
2023/10/06 23:00 59m bisect fix linux-5.15.y OK (0) job log log

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in udf_close_lvid+0x674/0x990 fs/udf/super.c:2108
Write of size 1 at addr ffff88809ab26098 by task syz-executor/4356

CPU: 1 PID: 4356 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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
 udf_close_lvid+0x674/0x990 fs/udf/super.c:2108
 udf_put_super+0xc8/0x160 fs/udf/super.c:2395
 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:1139
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 exit_task_work include/linux/task_work.h:33 [inline]
 do_exit+0x61e/0x20a0 kernel/exit.c:883
 do_group_exit+0x12e/0x300 kernel/exit.c:997
 get_signal+0x6ca/0x12c0 kernel/signal.c:2900
 arch_do_signal_or_restart+0xc1/0x1300 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xb1/0x140 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
RIP: 0033:0x7f7f7bbba69f
Code: Unable to access opcode bytes at RIP 0x7f7f7bbba675.
RSP: 002b:00007ffe08783e80 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: 0000000000000004 RBX: 0000000000000003 RCX: 00007f7f7bbba69f
RDX: 0000000000000004 RSI: 00007ffe08783f40 RDI: 00000000000000f8
RBP: 00007ffe08783eec R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 00000000000927c0 R14: 0000000000010cfe R15: 00007ffe08783f40
 </TASK>

The buggy address belongs to the page:
page:ffffea00026ac980 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x9ab26
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea00026ac988 ffffea00026ac988 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner info is not present (never set?)

Memory state around the buggy address:
 ffff88809ab25f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88809ab26000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88809ab26080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                            ^
 ffff88809ab26100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88809ab26180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================

Crashes (16):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/09/02 09:38 linux-5.15.y 01879f56bdde 807a3b61 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan KASAN: use-after-free Write in udf_close_lvid
2024/05/08 13:40 linux-5.15.y 284087d4f7d5 4cf3f9b3 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-linux-5-15-kasan KASAN: use-after-free Write in udf_close_lvid
2023/07/19 16:32 linux-5.15.y d54cfc420586 022df2bb .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-linux-5-15-kasan KASAN: use-after-free Write in udf_close_lvid
2023/06/08 21:43 linux-5.15.y d7af3e5ba454 058b3a5a .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-linux-5-15-kasan KASAN: use-after-free Write in udf_close_lvid
2023/06/08 16:11 linux-5.15.y d7af3e5ba454 058b3a5a .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-linux-5-15-kasan KASAN: use-after-free Write in udf_close_lvid
2023/05/29 07:12 linux-5.15.y 1fe619a7d252 cf184559 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-linux-5-15-kasan KASAN: use-after-free Write in udf_close_lvid
2023/05/23 16:31 linux-5.15.y 9d6bde853685 4bce1a3e .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-linux-5-15-kasan KASAN: use-after-free Write in udf_close_lvid
2024/04/19 12:55 linux-5.15.y c52b9710c83d af24b050 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-linux-5-15-kasan BUG: unable to handle kernel paging request in udf_close_lvid
2023/08/11 14:00 linux-5.15.y c275eaaaa342 da3c3ef8 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-linux-5-15-kasan KASAN: slab-out-of-bounds Write in udf_close_lvid
2023/06/19 05:45 linux-5.15.y 471e639e59d1 f3921d4d .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-linux-5-15-kasan BUG: unable to handle kernel paging request in udf_close_lvid
2023/05/28 19:13 linux-5.15.y 1fe619a7d252 cf184559 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-linux-5-15-kasan BUG: unable to handle kernel paging request in udf_close_lvid
2025/05/27 16:08 linux-5.15.y 98f47d0e9b8c 874a1386 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan BUG: unable to handle kernel paging request in udf_close_lvid
2023/12/14 21:30 linux-5.15.y d0fc081c6241 3222d10c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Write in udf_close_lvid
2025/08/25 11:25 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 udf_close_lvid
2024/04/22 22:45 linux-5.15.y c52b9710c83d 36c961ad .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan BUG: unable to handle kernel paging request in udf_close_lvid
2024/04/22 22:39 linux-5.15.y c52b9710c83d 36c961ad .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan BUG: unable to handle kernel paging request in udf_close_lvid
* Struck through repros no longer work on HEAD.