syzbot


UBSAN: shift-out-of-bounds in dbFindBits

Status: upstream: reported on 2024/07/08 13:36
Subsystems: jfs
[Documentation on labels]
Reported-by: syzbot+e38d703eeb410b17b473@syzkaller.appspotmail.com
First crash: 8d21h, last: 8d21h
Discussions (2)
Title Replies (including bot) Last reply
[PATCH] jfs: UBSAN: shift-out-of-bounds in dbFindBits 1 (1) 2024/07/10 00:12
[syzbot] [jfs?] UBSAN: shift-out-of-bounds in dbFindBits 0 (1) 2024/07/08 13:36

Sample crash report:
------------[ cut here ]------------
UBSAN: shift-out-of-bounds in fs/jfs/jfs_dmap.c:3023:47
shift exponent 32 is too large for 32-bit type 'u32' (aka 'unsigned int')
CPU: 0 PID: 7225 Comm: syz.0.177 Not tainted 6.10.0-rc6-syzkaller-00069-g795c58e4c7fc #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
 ubsan_epilogue lib/ubsan.c:231 [inline]
 __ubsan_handle_shift_out_of_bounds+0x3c8/0x420 lib/ubsan.c:468
 dbFindBits+0x11a/0x1d0 fs/jfs/jfs_dmap.c:3023
 dbAllocDmapLev+0x1e9/0x4a0 fs/jfs/jfs_dmap.c:1983
 dbAllocCtl+0x113/0x920 fs/jfs/jfs_dmap.c:1823
 dbAllocAG+0x28f/0x10b0 fs/jfs/jfs_dmap.c:1364
 dbDiscardAG+0x352/0xa10 fs/jfs/jfs_dmap.c:1613
 jfs_ioc_trim+0x433/0x670 fs/jfs/jfs_discard.c:100
 jfs_ioctl+0x2d0/0x3e0 fs/jfs/ioctl.c:131
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3713f75bd9
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:00007f3714cd5048 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f37141042c0 RCX: 00007f3713f75bd9
RDX: 0000000020000080 RSI: 00000000c0185879 RDI: 0000000000000007
RBP: 00007f3713fe4aa1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f37141042c0 R15: 00007ffe646d6a68
 </TASK>
---[ end trace ]---

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/07/04 13:27 upstream 795c58e4c7fc 3f2748a3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs UBSAN: shift-out-of-bounds in dbFindBits
* Struck through repros no longer work on HEAD.