syzbot


divide error in fbcon_init

Status: upstream: reported C repro on 2020/04/20 20:39
Reported-by: syzbot+949d8a55dc49138026b6@syzkaller.appspotmail.com
First crash: 1523d, last: 575d
Fix bisection: failed (error log, bisect log)
  
Fix bisection attempts (2)
Created Duration User Patch Repo Result
2020/06/21 04:58 0m bisect fix linux-4.14.y error job log (0)
2020/05/22 04:18 39m bisect fix linux-4.14.y job log (0) log

Sample crash report:
divide error: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 7990 Comm: syz-executor354 Not tainted 4.14.278-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8880b30ac600 task.stack: ffff88808d6e0000
RIP: 0010:fbcon_init+0xcb4/0x1cc0 drivers/video/fbdev/core/fbcon.c:1065
RSP: 0018:ffff88808d6e77e0 EFLAGS: 00010246
RAX: 0000000000000030 RBX: ffff888238eb7c80 RCX: 1ffff110471d6fc7
RDX: 0000000000000000 RSI: ffff88809a2cd834 RDI: ffff888238eb7e38
RBP: ffff88809a2cd480 R08: ffffffff8b9ba330 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880b04736c0
R13: 0000000000000008 R14: ffff88809a2cd7b4 R15: 0000000000000030
FS:  00005555556e1300(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4ec1b95033 CR3: 00000000ab2be000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 visual_init+0x332/0x5e0 drivers/tty/vt/vt.c:746
 vc_allocate+0x2c5/0x640 drivers/tty/vt/vt.c:802
 con_install+0x4d/0x450 drivers/tty/vt/vt.c:2916
 tty_driver_install_tty drivers/tty/tty_io.c:1225 [inline]
 tty_init_dev.part.0+0x99/0x400 drivers/tty/tty_io.c:1338
 tty_init_dev drivers/tty/tty_io.c:1328 [inline]
 tty_open_by_driver drivers/tty/tty_io.c:1973 [inline]
 tty_open+0x669/0x8b0 drivers/tty/tty_io.c:2021
 chrdev_open+0x23c/0x6d0 fs/char_dev.c:423
 do_dentry_open+0x44b/0xec0 fs/open.c:777
 vfs_open+0x105/0x220 fs/open.c:888
 do_last fs/namei.c:3428 [inline]
 path_openat+0x628/0x2970 fs/namei.c:3569
 do_filp_open+0x179/0x3c0 fs/namei.c:3603
 do_sys_open+0x296/0x410 fs/open.c:1081
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7f4ec1aff5b7
RSP: 002b:00007fff2bc6aaa0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00000000000076c6 RCX: 00007f4ec1aff5b7
RDX: 0000000000000002 RSI: 00007fff2bc6ab20 RDI: 00000000ffffff9c
RBP: 00007fff2bc6ab20 R08: 0000000000000000 R09: 000000000000000e
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000
Code: 54 24 30 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e 8d 0d 00 00 31 d2 44 89 f8 48 8b 74 24 38 <f7> b5 b0 03 00 00 48 89 f2 48 c1 ea 03 89 44 24 30 48 b8 00 00 
RIP: fbcon_init+0xcb4/0x1cc0 drivers/video/fbdev/core/fbcon.c:1065 RSP: ffff88808d6e77e0
---[ end trace a7de4f65769e5828 ]---
----------------
Code disassembly (best guess):
   0:	54                   	push   %rsp
   1:	24 30                	and    $0x30,%al
   3:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
   a:	fc ff df
   d:	48 c1 ea 03          	shr    $0x3,%rdx
  11:	0f b6 04 02          	movzbl (%rdx,%rax,1),%eax
  15:	84 c0                	test   %al,%al
  17:	74 08                	je     0x21
  19:	3c 03                	cmp    $0x3,%al
  1b:	0f 8e 8d 0d 00 00    	jle    0xdae
  21:	31 d2                	xor    %edx,%edx
  23:	44 89 f8             	mov    %r15d,%eax
  26:	48 8b 74 24 38       	mov    0x38(%rsp),%rsi
* 2b:	f7 b5 b0 03 00 00    	divl   0x3b0(%rbp) <-- trapping instruction
  31:	48 89 f2             	mov    %rsi,%rdx
  34:	48 c1 ea 03          	shr    $0x3,%rdx
  38:	89 44 24 30          	mov    %eax,0x30(%rsp)
  3c:	48                   	rex.W
  3d:	b8                   	.byte 0xb8

Crashes (22075):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/05/12 20:17 linux-4.14.y 569d1abf9402 9ad6612a .config console log report syz C ci2-linux-4-14 divide error in fbcon_init
2021/07/13 09:37 linux-4.14.y 4e68c9b0763f f415556d .config console log report syz C ci2-linux-4-14 divide error in fbcon_init
2021/06/22 19:00 linux-4.14.y cfb41ef9deb1 aba2b2fb .config console log report syz C ci2-linux-4-14 divide error in fbcon_init
2021/06/18 16:32 linux-4.14.y cfb41ef9deb1 aba2b2fb .config console log report syz C ci2-linux-4-14 divide error in fbcon_init
2021/05/18 19:23 linux-4.14.y 7d7d1c0ab3eb a343ba6b .config console log report syz C ci2-linux-4-14 divide error in fbcon_init
2021/05/18 13:57 linux-4.14.y 7d7d1c0ab3eb a343ba6b .config console log report syz C ci2-linux-4-14 divide error in fbcon_init
2021/05/11 23:41 linux-4.14.y 7d7d1c0ab3eb b3c3bb8e .config console log report syz C ci2-linux-4-14 divide error in fbcon_init
2021/05/04 04:33 linux-4.14.y 7d7d1c0ab3eb 09efdd63 .config console log report syz C ci2-linux-4-14 divide error in fbcon_init
2021/04/25 18:58 linux-4.14.y cf256fbcbe34 36c88236 .config console log report syz C ci2-linux-4-14 divide error in fbcon_init
2021/04/19 04:07 linux-4.14.y cf256fbcbe34 7e2b734b .config console log report syz C ci2-linux-4-14 divide error in fbcon_init
2021/04/18 19:56 linux-4.14.y cf256fbcbe34 7e2b734b .config console log report syz C ci2-linux-4-14 divide error in fbcon_init
2021/04/13 17:30 linux-4.14.y 958e517f4e16 6a81331a .config console log report syz C ci2-linux-4-14 divide error in fbcon_init
2021/04/11 05:15 linux-4.14.y 958e517f4e16 6a81331a .config console log report syz C ci2-linux-4-14 divide error in fbcon_init
2021/04/03 12:15 linux-4.14.y bd634aa64163 6a81331a .config console log report syz C ci2-linux-4-14 divide error in fbcon_init
2021/03/18 13:46 linux-4.14.y cb83ddcd5332 7216542e .config console log report syz C ci2-linux-4-14 divide error in fbcon_init
2021/03/18 01:11 linux-4.14.y cb83ddcd5332 fdb2bb2c .config console log report syz C ci2-linux-4-14 divide error in fbcon_init
2021/03/04 11:10 linux-4.14.y 397a88b2cc86 d7e4e604 .config console log report syz C ci2-linux-4-14 divide error in fbcon_init
2021/01/20 10:46 linux-4.14.y 2762b48e9611 d4f4eca5 .config console log report syz C ci2-linux-4-14 divide error in fbcon_init
2021/01/16 11:52 linux-4.14.y f79dc86058bc 65a7a854 .config console log report syz C ci2-linux-4-14
2020/12/29 16:20 linux-4.14.y 1752938529c6 80910769 .config console log report syz C ci2-linux-4-14
2020/12/28 06:44 linux-4.14.y 3f2ecb86cb90 2242f77f .config console log report syz C ci2-linux-4-14
2020/12/23 08:47 linux-4.14.y 3f2ecb86cb90 04201c06 .config console log report syz C ci2-linux-4-14
2020/12/22 10:16 linux-4.14.y 3f2ecb86cb90 04201c06 .config console log report syz C ci2-linux-4-14
2020/12/22 04:33 linux-4.14.y 3f2ecb86cb90 04201c06 .config console log report syz C ci2-linux-4-14
2020/12/19 20:14 linux-4.14.y 3f2ecb86cb90 04201c06 .config console log report syz C ci2-linux-4-14
2020/12/19 07:08 linux-4.14.y 3f2ecb86cb90 04201c06 .config console log report syz C ci2-linux-4-14
2020/11/30 21:27 linux-4.14.y 87335852c5d9 76831598 .config console log report syz C ci2-linux-4-14
2020/11/27 06:16 linux-4.14.y 87335852c5d9 5018c946 .config console log report syz C ci2-linux-4-14
2020/11/15 08:43 linux-4.14.y 27ce4f2a6817 1bf9a662 .config console log report syz C ci2-linux-4-14
2020/11/08 19:20 linux-4.14.y 6b6446efedb2 cba33199 .config console log report syz C ci2-linux-4-14
2020/10/29 11:56 linux-4.14.y 2b7915014161 f24824d3 .config console log report syz C ci2-linux-4-14
2020/10/07 19:38 linux-4.14.y cbfa1702aaf6 1880b4a9 .config console log report syz C ci2-linux-4-14
2020/09/02 03:17 linux-4.14.y d7e78d08fa77 abf9ba4f .config console log report syz C ci2-linux-4-14
2020/09/01 03:34 linux-4.14.y d7e78d08fa77 d5a3ae1f .config console log report syz C ci2-linux-4-14
2020/08/21 10:15 linux-4.14.y 6a24ca2506d6 1d75fe45 .config console log report syz C ci2-linux-4-14
2020/08/04 19:27 linux-4.14.y 7f2c5eb458b8 80a06902 .config console log report syz C ci2-linux-4-14
2020/04/22 04:18 linux-4.14.y c10b57a567e4 2e44d63e .config console log report syz C ci2-linux-4-14
2022/11/25 05:57 linux-4.14.y e911713e40ca 74a66371 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-4-14 divide error in fbcon_init
2022/11/23 10:35 linux-4.14.y e911713e40ca 52fdf57a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-4-14 divide error in fbcon_init
2022/11/17 17:13 linux-4.14.y e911713e40ca 4ba8ab94 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-4-14 divide error in fbcon_init
2022/11/15 02:12 linux-4.14.y e911713e40ca 97de9cfc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-4-14 divide error in fbcon_init
2022/11/09 06:21 linux-4.14.y a901bb6c7db7 5fa28208 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-4-14 divide error in fbcon_init
2022/11/07 13:45 linux-4.14.y a901bb6c7db7 a779b11a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-4-14 divide error in fbcon_init
2022/10/29 18:15 linux-4.14.y 41f36d7859a7 2a71366b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-4-14 divide error in fbcon_init
2022/10/26 21:14 linux-4.14.y 41f36d7859a7 86777b7f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-4-14 divide error in fbcon_init
2022/10/25 09:12 linux-4.14.y 9d5c0b3a8e1a 45645420 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/25 04:37 linux-4.14.y 9d5c0b3a8e1a 45645420 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/24 14:07 linux-4.14.y 9d5c0b3a8e1a faae2fda .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/22 06:53 linux-4.14.y 9d5c0b3a8e1a c0b80a55 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/21 10:05 linux-4.14.y 9d5c0b3a8e1a 63e790dd .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/21 02:13 linux-4.14.y 9d5c0b3a8e1a a0fd4dab .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/20 21:01 linux-4.14.y 9d5c0b3a8e1a a0fd4dab .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/18 11:24 linux-4.14.y 9d5c0b3a8e1a b31320fc .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/17 21:06 linux-4.14.y 9d5c0b3a8e1a 94744d21 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/17 19:40 linux-4.14.y 9d5c0b3a8e1a 94744d21 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/17 15:22 linux-4.14.y 9d5c0b3a8e1a 94744d21 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/15 02:43 linux-4.14.y 9d5c0b3a8e1a 67cb024c .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/14 02:54 linux-4.14.y 9d5c0b3a8e1a 4954e4b2 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/14 01:47 linux-4.14.y 9d5c0b3a8e1a 4954e4b2 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/14 00:31 linux-4.14.y 9d5c0b3a8e1a 4954e4b2 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/13 22:43 linux-4.14.y 9d5c0b3a8e1a 4954e4b2 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/13 20:21 linux-4.14.y 9d5c0b3a8e1a adf90437 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/12 18:19 linux-4.14.y 9d5c0b3a8e1a 16a9c9e0 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/11 04:21 linux-4.14.y 9d5c0b3a8e1a 5bcf0c31 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/11 01:22 linux-4.14.y 9d5c0b3a8e1a 5bcf0c31 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/10 19:16 linux-4.14.y 9d5c0b3a8e1a 5bcf0c31 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/10 17:47 linux-4.14.y 9d5c0b3a8e1a 5bcf0c31 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/10 15:15 linux-4.14.y 9d5c0b3a8e1a 5bcf0c31 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/10 14:42 linux-4.14.y 9d5c0b3a8e1a 5bcf0c31 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/08 07:21 linux-4.14.y 9d5c0b3a8e1a aea5da89 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/08 05:14 linux-4.14.y 9d5c0b3a8e1a aea5da89 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/07 11:47 linux-4.14.y 9d5c0b3a8e1a 79a59635 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/06 19:18 linux-4.14.y 9d5c0b3a8e1a 80b58a42 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/06 16:44 linux-4.14.y 9d5c0b3a8e1a 80b58a42 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/06 00:26 linux-4.14.y 9d5c0b3a8e1a 2c6543ad .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/10/05 02:21 linux-4.14.y 9d5c0b3a8e1a 267e3bb1 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/09/30 23:38 linux-4.14.y 9d5c0b3a8e1a feb56351 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/09/29 14:26 linux-4.14.y 9d5c0b3a8e1a 45fd7169 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/09/28 23:47 linux-4.14.y 9d5c0b3a8e1a a41a2080 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/09/28 19:27 linux-4.14.y 9d5c0b3a8e1a a41a2080 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 divide error in fbcon_init
2022/09/26 14:16 linux-4.14.y 4edbf74132a4 d59ba983 .config console log report info ci2-linux-4-14 divide error in fbcon_init
2022/09/26 12:27 linux-4.14.y 4edbf74132a4 d59ba983 .config console log report info ci2-linux-4-14 divide error in fbcon_init
2022/09/26 09:40 linux-4.14.y 4edbf74132a4 d59ba983 .config console log report info ci2-linux-4-14 divide error in fbcon_init
2021/01/17 14:12 linux-4.14.y 2762b48e9611 813be542 .config console log report info ci2-linux-4-14
2020/04/20 20:38 linux-4.14.y c10b57a567e4 347a5dc3 .config console log report ci2-linux-4-14
* Struck through repros no longer work on HEAD.