syzbot


UBSAN: shift-out-of-bounds in member_to_text

Status: upstream: reported C repro on 2024/09/02 18:57
Subsystems: bcachefs
[Documentation on labels]
Reported-by: syzbot+064ce437a1ad63d3f6ef@syzkaller.appspotmail.com
First crash: 14d, last: 10d
Discussions (2)
Title Replies (including bot) Last reply
[syzbot] [bcachefs?] UBSAN: shift-out-of-bounds in member_to_text 4 (6) 2024/09/08 14:14
[PATCH] bcachefs: Fix oob in member_to_text 1 (1) 2024/09/08 13:10
Last patch testing requests (1)
Created Duration User Patch Repo Result
2024/09/03 02:13 20m eadavis@qq.com patch upstream OK log

Sample crash report:
loop0: detected capacity change from 0 to 32768
------------[ cut here ]------------
UBSAN: shift-out-of-bounds in fs/bcachefs/sb-members.c:249:2
shift exponent 69 is too large for 64-bit type 'unsigned long long'
CPU: 0 UID: 0 PID: 5099 Comm: syz-executor454 Not tainted 6.11.0-rc6-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 ubsan_epilogue lib/ubsan.c:231 [inline]
 __ubsan_handle_shift_out_of_bounds+0x3c8/0x420 lib/ubsan.c:468
 member_to_text+0x9a2/0x9b0 fs/bcachefs/sb-members.c:249
 bch2_sb_members_v2_to_text+0x267/0x3b0 fs/bcachefs/sb-members.c:310
 bch2_sb_field_validate+0x201/0x2e0 fs/bcachefs/super-io.c:1233
 bch2_sb_validate+0xb4b/0xef0 fs/bcachefs/super-io.c:472
 __bch2_read_super+0xc1b/0x1370 fs/bcachefs/super-io.c:827
 bch2_fs_open+0x246/0xdf0 fs/bcachefs/super.c:2083
 bch2_fs_get_tree+0x731/0x1700 fs/bcachefs/fs.c:1933
 vfs_get_tree+0x90/0x2b0 fs/super.c:1800
 do_new_mount+0x2be/0xb40 fs/namespace.c:3472
 do_mount fs/namespace.c:3812 [inline]
 __do_sys_mount fs/namespace.c:4020 [inline]
 __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3997
 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: 0033:0x7fe3ee4d7faa
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 5e 04 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe262fa7b8 EFLAGS: 00000282 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffe262fa7d0 RCX: 00007fe3ee4d7faa
RDX: 00000000200058c0 RSI: 0000000020000100 RDI: 00007ffe262fa7d0
RBP: 0000000000000004 R08: 00007ffe262fa810 R09: 0000000000005903
R10: 0000000000000000 R11: 0000000000000282 R12: 0000000000000000
R13: 00007ffe262fa810 R14: 0000000000000003 R15: 0000000001000000
 </TASK>
---[ end trace ]---

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/09/01 20:53 upstream 431c1646e1f8 1eda0d14 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] [mounted in repro] ci-snapshot-upstream-root UBSAN: shift-out-of-bounds in member_to_text
2024/09/01 20:43 upstream 431c1646e1f8 1eda0d14 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] [mounted in repro] ci-snapshot-upstream-root UBSAN: shift-out-of-bounds in member_to_text
2024/09/06 15:53 upstream b831f83e40a2 ce70880a .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root UBSAN: shift-out-of-bounds in member_to_text
2024/09/06 15:47 upstream b831f83e40a2 ce70880a .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root UBSAN: shift-out-of-bounds in member_to_text
2024/09/01 20:32 upstream 431c1646e1f8 1eda0d14 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root UBSAN: shift-out-of-bounds in member_to_text
* Struck through repros no longer work on HEAD.