syzbot


BUG: unable to handle kernel paging request in sctp_outq_tail

Status: fixed on 2023/08/21 17:07
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+04d50f39111e013fc3ac@syzkaller.appspotmail.com
Fix commit: d2128636b303 sctp: check send stream number after wait_for_sndbuf
First crash: 622d, last: 517d
Fix bisection: fixed by (bisect log) :
commit d2128636b303aa9cf065055402ee6697409a8837
Author: Xin Long <lucien.xin@gmail.com>
Date: Sat Apr 1 23:09:57 2023 +0000

  sctp: check send stream number after wait_for_sndbuf

  
Bug presence (2)
Date Name Commit Repro Result
2023/05/15 linux-6.1.y (ToT) bf4ad6fa4e53 C [report] INFO: rcu detected stall in corrupted
2023/05/15 upstream (ToT) f1fcbaa18b28 C Didn't crash
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 BUG: unable to handle kernel paging request in sctp_outq_tail C done 2 592d 623d 3/3 fixed on 2023/05/11 04:30
upstream general protection fault in sctp_outq_tail sctp C error 5 597d 609d 22/28 fixed on 2023/06/08 14:41
Fix bisection attempts (4)
Created Duration User Patch Repo Result
2023/08/19 19:14 8h38m bisect fix linux-6.1.y OK (1) job log
2023/06/23 06:41 1h35m bisect fix linux-6.1.y OK (0) job log log
2023/05/23 17:17 52m bisect fix linux-6.1.y OK (0) job log log
2023/04/14 05:39 1h03m bisect fix linux-6.1.y OK (0) job log log

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc0000000007: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f]
CPU: 1 PID: 13960 Comm: syz-executor379 Not tainted 6.1.19-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
RIP: 0010:list_add_tail include/linux/list.h:102 [inline]
RIP: 0010:sctp_outq_tail_data net/sctp/outqueue.c:91 [inline]
RIP: 0010:sctp_outq_tail+0x2d9/0x910 net/sctp/outqueue.c:299
Code: 08 48 89 df e8 08 fa 0b f8 48 8b 2b 49 8d 5c 24 18 4c 8d 7d 30 48 83 c5 38 49 89 ed 49 c1 ed 03 48 b8 00 00 00 00 00 fc ff df <41> 80 7c 05 00 00 74 08 48 89 ef e8 d7 f9 0b f8 4c 8b 75 00 48 89
RSP: 0018:ffffc9000c977538 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff88801cadd8d8 RCX: ffff88807d2f0000
RDX: 0000000000000000 RSI: 00000000000000c0 RDI: 0000000000001001
RBP: 0000000000000038 R08: ffffffff843a63c2 R09: ffffffff89d4c950
R10: 0000000000000002 R11: ffff88807d2f0000 R12: ffff88801cadd8c0
R13: 0000000000000007 R14: ffff8880726507e0 R15: 0000000000000030
FS:  00007f93daea8700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f93dafa2480 CR3: 000000007d181000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 sctp_cmd_send_msg net/sctp/sm_sideeffect.c:1114 [inline]
 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1777 [inline]
 sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline]
 sctp_do_sm+0x3178/0x5c50 net/sctp/sm_sideeffect.c:1170
 sctp_primitive_SEND+0x94/0xc0 net/sctp/primitive.c:163
 sctp_sendmsg_to_asoc+0x110c/0x16f0 net/sctp/socket.c:1867
 sctp_sendmsg+0x1f49/0x3370 net/sctp/socket.c:2025
 sock_sendmsg_nosec net/socket.c:716 [inline]
 sock_sendmsg net/socket.c:736 [inline]
 __sys_sendto+0x471/0x5f0 net/socket.c:2117
 __do_sys_sendto net/socket.c:2129 [inline]
 __se_sys_sendto net/socket.c:2125 [inline]
 __x64_sys_sendto+0xda/0xf0 net/socket.c:2125
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f93daf20ad9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 61 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007f93daea81f8 EFLAGS: 00000212 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f93dafa2498 RCX: 00007f93daf20ad9
RDX: 0000000000034000 RSI: 0000000020000080 RDI: 0000000000000003
RBP: 00007f93dafa2490 R08: 00000000200005c0 R09: 000000000000001c
R10: 0000000000000000 R11: 0000000000000212 R12: 00007f93dafa249c
R13: 00007ffd9e40fbdf R14: 00007f93daea8300 R15: 0000000000022000
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:list_add_tail include/linux/list.h:102 [inline]
RIP: 0010:sctp_outq_tail_data net/sctp/outqueue.c:91 [inline]
RIP: 0010:sctp_outq_tail+0x2d9/0x910 net/sctp/outqueue.c:299
Code: 08 48 89 df e8 08 fa 0b f8 48 8b 2b 49 8d 5c 24 18 4c 8d 7d 30 48 83 c5 38 49 89 ed 49 c1 ed 03 48 b8 00 00 00 00 00 fc ff df <41> 80 7c 05 00 00 74 08 48 89 ef e8 d7 f9 0b f8 4c 8b 75 00 48 89
RSP: 0018:ffffc9000c977538 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff88801cadd8d8 RCX: ffff88807d2f0000
RDX: 0000000000000000 RSI: 00000000000000c0 RDI: 0000000000001001
RBP: 0000000000000038 R08: ffffffff843a63c2 R09: ffffffff89d4c950
R10: 0000000000000002 R11: ffff88807d2f0000 R12: ffff88801cadd8c0
R13: 0000000000000007 R14: ffff8880726507e0 R15: 0000000000000030
FS:  00007f93daea8700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020034000 CR3: 000000007d181000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	08 48 89             	or     %cl,-0x77(%rax)
   3:	df e8                	fucomip %st(0),%st
   5:	08 fa                	or     %bh,%dl
   7:	0b f8                	or     %eax,%edi
   9:	48 8b 2b             	mov    (%rbx),%rbp
   c:	49 8d 5c 24 18       	lea    0x18(%r12),%rbx
  11:	4c 8d 7d 30          	lea    0x30(%rbp),%r15
  15:	48 83 c5 38          	add    $0x38,%rbp
  19:	49 89 ed             	mov    %rbp,%r13
  1c:	49 c1 ed 03          	shr    $0x3,%r13
  20:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  27:	fc ff df
* 2a:	41 80 7c 05 00 00    	cmpb   $0x0,0x0(%r13,%rax,1) <-- trapping instruction
  30:	74 08                	je     0x3a
  32:	48 89 ef             	mov    %rbp,%rdi
  35:	e8 d7 f9 0b f8       	callq  0xf80bfa11
  3a:	4c 8b 75 00          	mov    0x0(%rbp),%r14
  3e:	48                   	rex.W
  3f:	89                   	.byte 0x89

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/03/15 05:39 linux-6.1.y 6449a0ba6843 0d5c4377 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan general protection fault in sctp_outq_tail
2023/03/10 01:47 linux-6.1.y 42616e0f09fb f08b59ac .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 BUG: unable to handle kernel paging request in sctp_outq_tail
* Struck through repros no longer work on HEAD.