syzbot


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

Status: upstream: reported on 2024/10/07 10:48
Reported-by: syzbot+7c2910d2b31421b7a9f2@syzkaller.appspotmail.com
First crash: 31d, last: 30d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 UBSAN: array-index-out-of-bounds in dbSplit C 9 23d 35d 0/3 upstream: reported C repro on 2024/10/03 12:39
upstream UBSAN: array-index-out-of-bounds in dbSplit jfs C inconclusive 31 56d 104d 28/28 fixed on 2024/10/22 11:57

Sample crash report:
================================================================================
UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dmap.c:2630:27
index 4294967295 is out of range for type 's8[1365]' (aka 'signed char[1365]')
CPU: 1 PID: 3774 Comm: syz.1.6 Not tainted 6.1.112-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 ubsan_epilogue lib/ubsan.c:151 [inline]
 __ubsan_handle_out_of_bounds+0x118/0x140 lib/ubsan.c:282
 dbSplit+0x1fd/0x220 fs/jfs/jfs_dmap.c:2630
 dbAllocBits+0x4e5/0x9a0 fs/jfs/jfs_dmap.c:2193
 dbAllocDmap fs/jfs/jfs_dmap.c:2034 [inline]
 dbAllocDmapLev+0x24c/0x490 fs/jfs/jfs_dmap.c:1988
 dbAllocCtl+0x113/0x920 fs/jfs/jfs_dmap.c:1825
 dbAllocAG+0x28b/0x10b0 fs/jfs/jfs_dmap.c:1364
 dbAlloc+0x654/0xc90 fs/jfs/jfs_dmap.c:888
 diNewIAG fs/jfs/jfs_imap.c:2510 [inline]
 diAllocExt fs/jfs/jfs_imap.c:1905 [inline]
 diAllocAG+0xa95/0x1e50 fs/jfs/jfs_imap.c:1669
 diAlloc+0x1cf/0x1750 fs/jfs/jfs_imap.c:1590
 ialloc+0x8b/0x970 fs/jfs/jfs_inode.c:56
 jfs_mkdir+0x1c1/0xbb0 fs/jfs/namei.c:225
 vfs_mkdir+0x3b6/0x590 fs/namei.c:4108
 do_mkdirat+0x225/0x360 fs/namei.c:4133
 __do_sys_mkdirat fs/namei.c:4148 [inline]
 __se_sys_mkdirat fs/namei.c:4146 [inline]
 __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4146
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7ff4c377dff9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff4c45b1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007ff4c3936058 RCX: 00007ff4c377dff9
RDX: 0000000000000000 RSI: 00000000200005c0 RDI: ffffffffffffff9c
RBP: 00007ff4c37f0296 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007ff4c3936058 R15: 00007ffdea1e2b08
 </TASK>
================================================================================

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/10/07 20:16 linux-6.1.y aa4cd140bba5 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan UBSAN: array-index-out-of-bounds in dbSplit
2024/10/07 20:14 linux-6.1.y aa4cd140bba5 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan UBSAN: array-index-out-of-bounds in dbSplit
2024/10/07 13:21 linux-6.1.y aa4cd140bba5 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan UBSAN: array-index-out-of-bounds in dbSplit
2024/10/07 10:47 linux-6.1.y aa4cd140bba5 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan UBSAN: array-index-out-of-bounds in dbSplit
2024/10/07 10:47 linux-6.1.y aa4cd140bba5 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan UBSAN: array-index-out-of-bounds in dbSplit
* Struck through repros no longer work on HEAD.