syzbot


general protection fault in cdev_del

Status: upstream: reported C repro on 2019/12/09 03:59
Subsystems: vfs
[Documentation on labels]
Reported-by: syzbot+66f836eb7f735883cb17@syzkaller.appspotmail.com
First crash: 1547d, last: 364d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in cdev_del (2) fs C error 45 979d 1257d 20/26 fixed on 2021/11/10 00:50
upstream general protection fault in cdev_del usb fs C 315 1274d 1742d 15/26 fixed on 2020/09/16 22:51
linux-4.14 general protection fault in cdev_del vfs C 279 365d 1552d 0/1 upstream: reported C repro on 2019/12/04 03:14
Fix bisection attempts (1)
Created Duration User Patch Repo Result
2021/04/24 13:27 31m bisect fix linux-4.19.y job log (0) log

Sample crash report:
RBP: 00007ffc3ffd54f0 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004
R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 8190 Comm: syz-executor703 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023
RIP: 0010:cdev_del+0x22/0x90 fs/char_dev.c:602
Code: cf 0f 1f 80 00 00 00 00 55 48 89 fd 48 83 ec 08 e8 b3 dc be ff 48 8d 7d 64 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 4f 48
RSP: 0018:ffff88808ee8fba0 EFLAGS: 00010207
RAX: dffffc0000000000 RBX: ffff8880af26c100 RCX: ffffffff83b8674f
RDX: 000000000000000c RSI: ffffffff81a3a8bd RDI: 0000000000000064
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000007 R11: 0000000000000000 R12: ffff8880af26c108
R13: ffff8882388fcb08 R14: ffff8880a465b980 R15: ffff8880a16087b8
FS:  0000555555bb6300(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fde66865290 CR3: 00000000a1271000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 tty_unregister_device drivers/tty/tty_io.c:3054 [inline]
 tty_unregister_device+0x112/0x1b0 drivers/tty/tty_io.c:3049
 gsmld_detach_gsm drivers/tty/n_gsm.c:2289 [inline]
 gsmld_close+0xaa/0x1f0 drivers/tty/n_gsm.c:2358
 tty_ldisc_close+0xa2/0xd0 drivers/tty/tty_ldisc.c:493
 tty_ldisc_kill drivers/tty/tty_ldisc.c:639 [inline]
 tty_ldisc_release+0xf5/0x440 drivers/tty/tty_ldisc.c:806
 tty_release_struct+0x20/0xe0 drivers/tty/tty_io.c:1611
 tty_release+0xc70/0x1210 drivers/tty/tty_io.c:1784
 __fput+0x2ce/0x890 fs/file_table.c:278
 task_work_run+0x148/0x1c0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xbf3/0x2be0 kernel/exit.c:870
 do_group_exit+0x125/0x310 kernel/exit.c:967
 __do_sys_exit_group kernel/exit.c:978 [inline]
 __se_sys_exit_group kernel/exit.c:976 [inline]
 __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:976
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fde667efd09
Code: Bad RIP value.
RSP: 002b:00007ffc3ffd5488 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007fde668643f0 RCX: 00007fde667efd09
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffffffffffc0 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fde668643f0
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001
Modules linked in:
---[ end trace 309685986feb61cd ]---
RIP: 0010:cdev_del+0x22/0x90 fs/char_dev.c:602
Code: cf 0f 1f 80 00 00 00 00 55 48 89 fd 48 83 ec 08 e8 b3 dc be ff 48 8d 7d 64 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 4f 48
RSP: 0018:ffff88808ee8fba0 EFLAGS: 00010207
RAX: dffffc0000000000 RBX: ffff8880af26c100 RCX: ffffffff83b8674f
RDX: 000000000000000c RSI: ffffffff81a3a8bd RDI: 0000000000000064
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000007 R11: 0000000000000000 R12: ffff8880af26c108
R13: ffff8882388fcb08 R14: ffff8880a465b980 R15: ffff8880a16087b8
FS:  0000555555bb6300(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055b5ed0b5160 CR3: 00000000b4c5d000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	cf                   	iret
   1:	0f 1f 80 00 00 00 00 	nopl   0x0(%rax)
   8:	55                   	push   %rbp
   9:	48 89 fd             	mov    %rdi,%rbp
   c:	48 83 ec 08          	sub    $0x8,%rsp
  10:	e8 b3 dc be ff       	callq  0xffbedcc8
  15:	48 8d 7d 64          	lea    0x64(%rbp),%rdi
  19:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  20:	fc ff df
  23:	48 89 fa             	mov    %rdi,%rdx
  26:	48 c1 ea 03          	shr    $0x3,%rdx
* 2a:	0f b6 14 02          	movzbl (%rdx,%rax,1),%edx <-- trapping instruction
  2e:	48 89 f8             	mov    %rdi,%rax
  31:	83 e0 07             	and    $0x7,%eax
  34:	83 c0 03             	add    $0x3,%eax
  37:	38 d0                	cmp    %dl,%al
  39:	7c 04                	jl     0x3f
  3b:	84 d2                	test   %dl,%dl
  3d:	75 4f                	jne    0x8e
  3f:	48                   	rex.W

Crashes (415):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/01/29 08:17 linux-4.19.y 3f8a27f9e27b 9dfcf09c .config console log report syz C [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2023/01/18 06:49 linux-4.19.y 3f8a27f9e27b 42660d9e .config console log report syz C [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/10/08 09:59 linux-4.19.y 3f8a27f9e27b aea5da89 .config console log report syz C [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/06/30 06:41 linux-4.19.y 3f8a27f9e27b 1434eec0 .config console log report syz C ci2-linux-4-19 general protection fault in cdev_del
2022/05/20 21:43 linux-4.19.y 3f8a27f9e27b bd37ad7e .config console log report syz C ci2-linux-4-19 general protection fault in cdev_del
2022/05/13 01:04 linux-4.19.y 3f8a27f9e27b 9ad6612a .config console log report syz C ci2-linux-4-19 general protection fault in cdev_del
2019/12/13 01:12 linux-4.19.y fb683b5e3f53 08003f64 .config console log report syz C ci2-linux-4-19
2023/03/06 18:18 linux-4.19.y 3f8a27f9e27b f8902b57 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2023/03/02 22:40 linux-4.19.y 3f8a27f9e27b f8902b57 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2023/03/01 16:04 linux-4.19.y 3f8a27f9e27b ef65e6cb .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2023/03/01 03:53 linux-4.19.y 3f8a27f9e27b 95aee97a .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2023/02/14 11:04 linux-4.19.y 3f8a27f9e27b 93ae7e0a .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2023/02/13 23:05 linux-4.19.y 3f8a27f9e27b 957959cb .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2023/02/13 21:28 linux-4.19.y 3f8a27f9e27b 957959cb .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2023/02/13 19:02 linux-4.19.y 3f8a27f9e27b 957959cb .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2023/02/07 23:54 linux-4.19.y 3f8a27f9e27b 15c3d445 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2023/02/05 16:57 linux-4.19.y 3f8a27f9e27b be607b78 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2023/02/03 01:02 linux-4.19.y 3f8a27f9e27b 16d19e30 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2023/01/23 20:53 linux-4.19.y 3f8a27f9e27b 9dfcf09c .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2023/01/21 12:16 linux-4.19.y 3f8a27f9e27b cc0f9968 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2023/01/20 00:26 linux-4.19.y 3f8a27f9e27b 71197f3a .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2023/01/18 06:34 linux-4.19.y 3f8a27f9e27b 42660d9e .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2023/01/12 17:20 linux-4.19.y 3f8a27f9e27b 96166539 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2023/01/11 00:42 linux-4.19.y 3f8a27f9e27b 48bc529a .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2023/01/04 11:54 linux-4.19.y 3f8a27f9e27b 1dac8c7a .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2023/01/03 07:22 linux-4.19.y 3f8a27f9e27b ab32d508 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/12/21 01:47 linux-4.19.y 3f8a27f9e27b d3e76707 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/12/20 16:05 linux-4.19.y 3f8a27f9e27b c52b2efb .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/12/19 14:24 linux-4.19.y 3f8a27f9e27b 05494336 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/12/18 06:33 linux-4.19.y 3f8a27f9e27b 05494336 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/12/10 22:00 linux-4.19.y 3f8a27f9e27b 67be1ae7 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/12/07 10:45 linux-4.19.y 3f8a27f9e27b d88f3abb .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/12/02 05:03 linux-4.19.y 3f8a27f9e27b e080de16 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/11/30 15:29 linux-4.19.y 3f8a27f9e27b 4c2a66e8 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/11/26 10:12 linux-4.19.y 3f8a27f9e27b f4470a7b .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/11/23 01:49 linux-4.19.y 3f8a27f9e27b 9da37ae8 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/11/22 17:52 linux-4.19.y 3f8a27f9e27b 9da37ae8 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/11/16 18:59 linux-4.19.y 3f8a27f9e27b 3a127a31 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/11/15 20:26 linux-4.19.y 3f8a27f9e27b 97de9cfc .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/11/11 08:35 linux-4.19.y 3f8a27f9e27b f42ee5d8 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/11/10 07:42 linux-4.19.y 3f8a27f9e27b b2488a87 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/11/04 02:43 linux-4.19.y 3f8a27f9e27b 6d752409 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/11/02 02:18 linux-4.19.y 3f8a27f9e27b 08977f5d .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/10/29 11:38 linux-4.19.y 3f8a27f9e27b 899d812a .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/10/28 04:05 linux-4.19.y 3f8a27f9e27b 5c716ff6 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/10/26 06:24 linux-4.19.y 3f8a27f9e27b 2159e4d2 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/10/26 04:29 linux-4.19.y 3f8a27f9e27b 2159e4d2 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/10/18 20:55 linux-4.19.y 3f8a27f9e27b b31320fc .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/10/18 04:36 linux-4.19.y 3f8a27f9e27b 94744d21 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/10/16 09:41 linux-4.19.y 3f8a27f9e27b 67cb024c .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/10/15 05:36 linux-4.19.y 3f8a27f9e27b 67cb024c .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/10/15 03:39 linux-4.19.y 3f8a27f9e27b 67cb024c .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2022/10/13 18:50 linux-4.19.y 3f8a27f9e27b adf90437 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 general protection fault in cdev_del
2021/01/08 15:13 linux-4.19.y 4143d798313f c104d4a3 .config console log report info ci2-linux-4-19
2019/12/09 03:59 linux-4.19.y fb683b5e3f53 1508f453 .config console log report ci2-linux-4-19
* Struck through repros no longer work on HEAD.