syzbot


UBSAN: undefined-behaviour in chkSuper

Status: upstream: reported C repro on 2020/09/22 04:30
Reported-by: syzbot+93832818c5634b9e5cfa@syzkaller.appspotmail.com
First crash: 1337d, last: 1310d
Fix bisection: failed (error log, bisect log)
  

Sample crash report:
audit: type=1400 audit(1602258842.646:8): avc:  denied  { execmem } for  pid=6489 comm="syz-executor834" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1
================================================================================
UBSAN: Undefined behaviour in fs/jfs/jfs_mount.c:385:25
shift exponent 6156 is too large for 32-bit type 'int'
CPU: 0 PID: 6489 Comm: syz-executor834 Not tainted 4.19.150-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x22c/0x33e lib/dump_stack.c:118
 ubsan_epilogue+0xe/0x3a lib/ubsan.c:161
 __ubsan_handle_shift_out_of_bounds.cold+0x1c4/0x250 lib/ubsan.c:422
 chkSuper.cold+0x1e/0x98 fs/jfs/jfs_mount.c:385
 jfs_mount+0x47/0x3d0 fs/jfs/jfs_mount.c:94
 jfs_fill_super+0x55c/0xb50 fs/jfs/super.c:589
 mount_bdev+0x2fc/0x3b0 fs/super.c:1158
 mount_fs+0xa3/0x318 fs/super.c:1261
 vfs_kern_mount.part.0+0x68/0x470 fs/namespace.c:961
 vfs_kern_mount fs/namespace.c:951 [inline]
 do_new_mount fs/namespace.c:2469 [inline]
 do_mount+0x51c/0x2f10 fs/namespace.c:2799
 ksys_mount+0xcf/0x130 fs/namespace.c:3015
 __do_sys_mount fs/namespace.c:3029 [inline]
 __se_sys_mount fs/namespace.c:3026 [inline]
 __x64_sys_mount+0xba/0x150 fs/namespace.c:3026
 do_syscall_64+0xf9/0x670 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x446d4a
Code: b8 08 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 fd ad fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 da ad fb ff c3 66 0f 1f 84 00 00 00 00 00
RSP: 002b:00007fff527f6dc8 EFLAGS: 00000283 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fff527f6e20 RCX: 0000000000446d4a
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007fff527f6de0
RBP: 00007fff527f6de0 R08: 00007fff527f6e20 R09: 00007fff00000015
R10: 0000000000000000 R11: 0000000000000283 R12: 0000000000000001
R13: 0000000000000004 R14: 0000000000000003 R15: 0000000000000003
================================================================================
================================================================================
UBSAN: Undefined behaviour in fs/jfs/jfs_imap.c:458:7
shift exponent -6144 is negative
CPU: 0 PID: 6489 Comm: syz-executor834 Not tainted 4.19.150-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x22c/0x33e lib/dump_stack.c:118
 ubsan_epilogue+0xe/0x3a lib/ubsan.c:161
 __ubsan_handle_shift_out_of_bounds.cold+0x1c4/0x250 lib/ubsan.c:422
 diReadSpecial.cold+0x1b/0x3e fs/jfs/jfs_imap.c:458
 jfs_mount+0x83/0x3d0 fs/jfs/jfs_mount.c:98
 jfs_fill_super+0x55c/0xb50 fs/jfs/super.c:589
 mount_bdev+0x2fc/0x3b0 fs/super.c:1158
 mount_fs+0xa3/0x318 fs/super.c:1261
 vfs_kern_mount.part.0+0x68/0x470 fs/namespace.c:961
 vfs_kern_mount fs/namespace.c:951 [inline]
 do_new_mount fs/namespace.c:2469 [inline]
 do_mount+0x51c/0x2f10 fs/namespace.c:2799
 ksys_mount+0xcf/0x130 fs/namespace.c:3015
 __do_sys_mount fs/namespace.c:3029 [inline]
 __se_sys_mount fs/namespace.c:3026 [inline]
 __x64_sys_mount+0xba/0x150 fs/namespace.c:3026
 do_syscall_64+0xf9/0x670 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x446d4a
Code: b8 08 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 fd ad fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 da ad fb ff c3 66 0f 1f 84 00 00 00 00 00
RSP: 002b:00007fff527f6dc8 EFLAGS: 00000283 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fff527f6e20 RCX: 0000000000446d4a
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007fff527f6de0
RBP: 00007fff527f6de0 R08: 00007fff527f6e20 R09: 00007fff00000015
R10: 0000000000000000 R11: 0000000000000283 R12: 0000000000000001
R13: 0000000000000004 R14: 0000000000000003 R15: 0000000000000003
================================================================================
================================================================================
UBSAN: Undefined behaviour in fs/jfs/jfs_imap.c:126:7
shift exponent -6144 is negative
CPU: 0 PID: 6489 Comm: syz-executor834 Not tainted 4.19.150-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x22c/0x33e lib/dump_stack.c:118
 ubsan_epilogue+0xe/0x3a lib/ubsan.c:161
 __ubsan_handle_shift_out_of_bounds.cold+0x1c4/0x250 lib/ubsan.c:422
 diMount.cold+0x17/0x1c fs/jfs/jfs_imap.c:126
 jfs_mount+0xbf/0x3d0 fs/jfs/jfs_mount.c:111
 jfs_fill_super+0x55c/0xb50 fs/jfs/super.c:589
 mount_bdev+0x2fc/0x3b0 fs/super.c:1158
 mount_fs+0xa3/0x318 fs/super.c:1261
 vfs_kern_mount.part.0+0x68/0x470 fs/namespace.c:961
 vfs_kern_mount fs/namespace.c:951 [inline]
 do_new_mount fs/namespace.c:2469 [inline]
 do_mount+0x51c/0x2f10 fs/namespace.c:2799
 ksys_mount+0xcf/0x130 fs/namespace.c:3015
 __do_sys_mount fs/namespace.c:3029 [inline]
 __se_sys_mount fs/namespace.c:3026 [inline]
 __x64_sys_mount+0xba/0x150 fs/namespace.c:3026
 do_syscall_64+0xf9/0x670 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x446d4a
Code: b8 08 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 fd ad fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 da ad fb ff c3 66 0f 1f 84 00 00 00 00 00
RSP: 002b:00007fff527f6dc8 EFLAGS: 00000283 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fff527f6e20 RCX: 0000000000446d4a
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007fff527f6de0
RBP: 00007fff527f6de0 R08: 00007fff527f6e20 R09: 00007fff00000015
R10: 0000000000000000 R11: 0000000000000283 R12: 0000000000000001
R13: 0000000000000004 R14: 0000000000000003 R15: 0000000000000003
================================================================================

Crashes (26):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/10/09 15:55 linux-4.19.y a1b977b49b66 fa79ed2a .config console log report syz C ci2-linux-4-19
2020/09/22 04:40 linux-4.19.y 015e94d0e37b 9e1fa68e .config console log report syz C ci2-linux-4-19
2020/10/18 15:21 linux-4.19.y ad326970d25c fea47c01 .config console log report info ci2-linux-4-19
2020/10/16 18:37 linux-4.19.y a1b977b49b66 6e262c73 .config console log report info ci2-linux-4-19
2020/10/11 01:42 linux-4.19.y a1b977b49b66 4a77ae0b .config console log report info ci2-linux-4-19
2020/10/06 12:23 linux-4.19.y b09c34517e1a 1880b4a9 .config console log report info ci2-linux-4-19
2020/10/06 07:57 linux-4.19.y b09c34517e1a 1880b4a9 .config console log report info ci2-linux-4-19
2020/10/03 18:14 linux-4.19.y b09c34517e1a 1a3f9408 .config console log report info ci2-linux-4-19
2020/10/03 15:21 linux-4.19.y b09c34517e1a 2653fa43 .config console log report info ci2-linux-4-19
2020/10/02 20:35 linux-4.19.y b09c34517e1a 062c9832 .config console log report info ci2-linux-4-19
2020/10/01 02:05 linux-4.19.y 10ad6cfd5736 a9767fb2 .config console log report info ci2-linux-4-19
2020/09/29 19:00 linux-4.19.y 10ad6cfd5736 5abc3f1a .config console log report info ci2-linux-4-19
2020/09/29 17:40 linux-4.19.y 10ad6cfd5736 5abc3f1a .config console log report info ci2-linux-4-19
2020/09/29 13:31 linux-4.19.y 10ad6cfd5736 1b88c6d5 .config console log report info ci2-linux-4-19
2020/09/28 04:59 linux-4.19.y 10ad6cfd5736 5dd8aee8 .config console log report info ci2-linux-4-19
2020/09/27 06:46 linux-4.19.y 10ad6cfd5736 5dd8aee8 .config console log report info ci2-linux-4-19
2020/09/27 03:25 linux-4.19.y 10ad6cfd5736 5dd8aee8 .config console log report info ci2-linux-4-19
2020/09/26 03:50 linux-4.19.y d09b80172c22 4a006f63 .config console log report info ci2-linux-4-19
2020/09/25 21:55 linux-4.19.y d09b80172c22 4a006f63 .config console log report info ci2-linux-4-19
2020/09/25 19:13 linux-4.19.y d09b80172c22 4a006f63 .config console log report info ci2-linux-4-19
2020/09/24 23:49 linux-4.19.y d09b80172c22 54289b08 .config console log report info ci2-linux-4-19
2020/09/24 23:39 linux-4.19.y d09b80172c22 54289b08 .config console log report info ci2-linux-4-19
2020/09/24 09:02 linux-4.19.y d09b80172c22 54289b08 .config console log report info ci2-linux-4-19
2020/09/24 06:37 linux-4.19.y d09b80172c22 54289b08 .config console log report info ci2-linux-4-19
2020/09/23 04:30 linux-4.19.y 015e94d0e37b 3e8f6c27 .config console log report info ci2-linux-4-19
2020/09/22 04:29 linux-4.19.y 015e94d0e37b 9e1fa68e .config console log report info ci2-linux-4-19
* Struck through repros no longer work on HEAD.