UBSAN: array-index-out-of-bounds in add_missing_indices

Status: upstream: reported C repro on 2025/02/02 08:00
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+5350f3210980ec3c4b43@syzkaller.appspotmail.com
First crash: 544d, last: 419d
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2025/03/22 upstream (ToT) 183601b78a9b C [report] UBSAN: array-index-out-of-bounds in add_missing_indices
▶ ▼ Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream UBSAN: array-index-out-of-bounds in add_missing_indices jfs 15 syz, C 187 416d 612d 29/29 fixed on 2025/07/08 00:33
linux-6.6 UBSAN: array-index-out-of-bounds in add_missing_indices origin:upstream missing-backport 15 syz, C error 22 71d 391d 0/2 upstream: reported C repro on 2025/07/04 21:27
linux-6.1 UBSAN: array-index-out-of-bounds in add_missing_indices origin:upstream missing-backport 19 syz, C inconclusive 12 195d 564d 0/3 upstream: reported C repro on 2025/01/13 05:49
▶ ▼ Last patch testing requests (10)
Created Duration User Patch Repo Result
2026/06/19 11:10 21m retest repro linux-5.15.y report log
2026/05/09 08:09 18m retest repro linux-5.15.y report log
2026/04/08 09:52 12m retest repro linux-5.15.y report log
2026/02/16 03:53 13m retest repro linux-5.15.y report log
2026/01/28 05:39 12m retest repro linux-5.15.y report log
2025/12/07 16:45 16m retest repro linux-5.15.y report log
2025/11/18 20:45 1m retest repro linux-5.15.y error
2025/09/27 21:43 13m retest repro linux-5.15.y report log
2025/09/08 03:12 17m retest repro linux-5.15.y report log
2025/07/19 11:03 15m retest repro linux-5.15.y report log

Sample crash report:
 ... Log Wrap ... Log Wrap ... Log Wrap ...
================================================================================
UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dtree.c:2945:28
index -128 is out of range for type 'struct dtslot[128]'
CPU: 0 PID: 4019 Comm: syz-executor179 Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call trace:
 dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 dump_stack+0x1c/0x58 lib/dump_stack.c:113
 ubsan_epilogue lib/ubsan.c:151 [inline]
 __ubsan_handle_out_of_bounds+0x108/0x15c lib/ubsan.c:282
 add_missing_indices+0x6e8/0xaa8 fs/jfs/jfs_dtree.c:2945
 jfs_readdir+0x1948/0x3030 fs/jfs/jfs_dtree.c:3315
 iterate_dir+0x1f4/0x4ec
 __do_sys_getdents64 fs/readdir.c:369 [inline]
 __se_sys_getdents64 fs/readdir.c:354 [inline]
 __arm64_sys_getdents64+0x1c4/0x4c4 fs/readdir.c:354
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
================================================================================
==================================================================
BUG: KASAN: slab-out-of-bounds in diWrite+0xb48/0x1604 fs/jfs/jfs_imap.c:753
Read of size 32 at addr ffff0000d472c130 by task syz-executor179/4019

CPU: 0 PID: 4019 Comm: syz-executor179 Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call trace:
 dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 print_address_description+0x7c/0x3f0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0x174/0x1e4 mm/kasan/report.c:451
 kasan_check_range+0x274/0x2b4 mm/kasan/generic.c:189
 memcpy+0x90/0xe8 mm/kasan/shadow.c:65
 diWrite+0xb48/0x1604 fs/jfs/jfs_imap.c:753
 txCommit+0x754/0x55b0 fs/jfs/jfs_txnmgr.c:1255
 add_missing_indices+0x764/0xaa8 fs/jfs/jfs_dtree.c:2959
 jfs_readdir+0x1948/0x3030 fs/jfs/jfs_dtree.c:3315
 iterate_dir+0x1f4/0x4ec
 __do_sys_getdents64 fs/readdir.c:369 [inline]
 __se_sys_getdents64 fs/readdir.c:354 [inline]
 __arm64_sys_getdents64+0x1c4/0x4c4 fs/readdir.c:354
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

Allocated by task 0:
(stack is not available)

The buggy address belongs to the object at ffff0000d472c0c0
 which belongs to the cache jfs_ip of size 2240
The buggy address is located 112 bytes inside of
 2240-byte region [ffff0000d472c0c0, ffff0000d472c980)
The buggy address belongs to the page:
page:00000000c86e30d4 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x114728
head:00000000c86e30d4 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000010200 0000000000000000 dead000000000122 ffff0000c6904000
raw: 0000000000000000 00000000800d000d 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000d472c000: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
 ffff0000d472c080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff0000d472c100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                     ^
 ffff0000d472c180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff0000d472c200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

 ... Log Wrap ... Log Wrap ... Log Wrap ...


 ... Log Wrap ... Log Wrap ... Log Wrap ...


 ... Log Wrap ... Log Wrap ... Log Wrap ...

ERROR: (device loop0): jfs_readdir: JFS:Dtree error: ino = 2, bn=0, index = 0

ERROR: (device loop0): remounting filesystem as read-only
JFS: Invalid stbl[1] = -128 for inode 2, block = 0

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/02/02 14:15 linux-5.15.y c16c81c81336 568559e4 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 UBSAN: array-index-out-of-bounds in add_missing_indices
2025/02/02 09:26 linux-5.15.y c16c81c81336 568559e4 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 UBSAN: array-index-out-of-bounds in add_missing_indices
2025/03/08 05:24 linux-5.15.y c16c81c81336 7e3bd60d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 UBSAN: array-index-out-of-bounds in add_missing_indices
2025/02/08 22:46 linux-5.15.y c16c81c81336 ef44b750 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 UBSAN: array-index-out-of-bounds in add_missing_indices
2025/02/02 08:00 linux-5.15.y c16c81c81336 568559e4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 UBSAN: array-index-out-of-bounds in add_missing_indices
2025/06/06 16:58 linux-5.15.y 1c700860e8bc 9fa58bba .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in add_missing_indices
2025/06/02 09:21 linux-5.15.y 98f47d0e9b8c 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: slab-out-of-bounds Read in add_missing_indices
* Struck through repros no longer work on HEAD.