syzbot


general protection fault in slip_receive_buf

Status: auto-obsoleted due to no activity on 2023/10/24 19:58
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+d287c0c38d54942a4e3c@syzkaller.appspotmail.com
First crash: 500d, last: 500d

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 PID: 57 Comm: kworker/u4:4 Not tainted 6.5.0-rc3-syzkaller-00024-g18b44bc5a672 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023
Workqueue: events_unbound flush_to_ldisc
RIP: 0010:slip_unesc drivers/net/slip/slip.c:987 [inline]
RIP: 0010:slip_receive_buf+0x412/0xbe0 drivers/net/slip/slip.c:709
Code: 02 00 0f 85 a0 07 00 00 41 8d 47 01 4c 03 bb b0 00 00 00 89 83 b8 00 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 fa 48 c1 ea 03 <0f> b6 04 02 4c 89 fa 83 e2 07 38 d0 7f 0c 84 c0 74 08 4c 89 ff e8
RSP: 0018:ffffc90001587b88 EFLAGS: 00010256
RAX: dffffc0000000000 RBX: ffff88803b92cc80 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff85d225be RDI: ffff88803b92cd30
RBP: 0000000000000000 R08: 0000000000000004 R09: 0000000000000000
R10: 0000000000000480 R11: 000000000000004e R12: dffffc0000000000
R13: ffff88803b92cd68 R14: ffff8880385c916a R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020006000 CR3: 000000002af04000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 tty_ldisc_receive_buf+0x143/0x180 drivers/tty/tty_buffer.c:461
 tty_port_default_receive_buf+0x6f/0xa0 drivers/tty/tty_port.c:39
 receive_buf drivers/tty/tty_buffer.c:515 [inline]
 flush_to_ldisc+0x252/0x7c0 drivers/tty/tty_buffer.c:565
 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2597
 worker_thread+0x687/0x1110 kernel/workqueue.c:2748
 kthread+0x33a/0x430 kernel/kthread.c:389
 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:296
RIP: 0000:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 0000:0000000000000000 EFLAGS: 00000000 ORIG_RAX: 0000000000000000
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:slip_unesc drivers/net/slip/slip.c:987 [inline]
RIP: 0010:slip_receive_buf+0x412/0xbe0 drivers/net/slip/slip.c:709
Code: 02 00 0f 85 a0 07 00 00 41 8d 47 01 4c 03 bb b0 00 00 00 89 83 b8 00 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 fa 48 c1 ea 03 <0f> b6 04 02 4c 89 fa 83 e2 07 38 d0 7f 0c 84 c0 74 08 4c 89 ff e8
RSP: 0018:ffffc90001587b88 EFLAGS: 00010256
RAX: dffffc0000000000 RBX: ffff88803b92cc80 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff85d225be RDI: ffff88803b92cd30
RBP: 0000000000000000 R08: 0000000000000004 R09: 0000000000000000
R10: 0000000000000480 R11: 000000000000004e R12: dffffc0000000000
R13: ffff88803b92cd68 R14: ffff8880385c916a R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9ff0ef7378 CR3: 000000002792f000 CR4: 0000000000350ee0
----------------
Code disassembly (best guess):
   0:	02 00                	add    (%rax),%al
   2:	0f 85 a0 07 00 00    	jne    0x7a8
   8:	41 8d 47 01          	lea    0x1(%r15),%eax
   c:	4c 03 bb b0 00 00 00 	add    0xb0(%rbx),%r15
  13:	89 83 b8 00 00 00    	mov    %eax,0xb8(%rbx)
  19:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  20:	fc ff df
  23:	4c 89 fa             	mov    %r15,%rdx
  26:	48 c1 ea 03          	shr    $0x3,%rdx
* 2a:	0f b6 04 02          	movzbl (%rdx,%rax,1),%eax <-- trapping instruction
  2e:	4c 89 fa             	mov    %r15,%rdx
  31:	83 e2 07             	and    $0x7,%edx
  34:	38 d0                	cmp    %dl,%al
  36:	7f 0c                	jg     0x44
  38:	84 c0                	test   %al,%al
  3a:	74 08                	je     0x44
  3c:	4c 89 ff             	mov    %r15,%rdi
  3f:	e8                   	.byte 0xe8

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/07/26 19:58 upstream 18b44bc5a672 41fe1bae .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root general protection fault in slip_receive_buf
* Struck through repros no longer work on HEAD.