syzbot


BUG: unable to handle kernel paging request in vsscanf (3)

Status: auto-closed as invalid on 2022/08/22 19:56
Reported-by: syzbot+c2fd72a3a5f9d85a5ff8@syzkaller.appspotmail.com
First crash: 958d, last: 958d
Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 BUG: unable to handle kernel paging request in vsscanf 1 1696d 1696d 0/1 auto-closed as invalid on 2020/08/14 14:44
linux-4.19 BUG: unable to handle kernel paging request in vsscanf 2 1558d 1593d 0/1 auto-closed as invalid on 2020/12/30 13:41
upstream BUG: unable to handle kernel paging request in vsscanf (2) net 1 1615d 1615d 0/28 auto-closed as invalid on 2020/10/04 11:58
linux-4.19 BUG: unable to handle kernel paging request in vsscanf (2) 2 1150d 1252d 0/1 auto-closed as invalid on 2022/02/11 22:53
upstream BUG: unable to handle kernel paging request in vsscanf bridge 1 1776d 1776d 0/28 auto-closed as invalid on 2020/04/26 09:37
upstream KMSAN: uninit-value in vsscanf bluetooth syz 9 1011d 1077d 0/28 auto-closed as invalid on 2022/09/27 18:52

Sample crash report:
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'.
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.5'.
BUG: unable to handle kernel paging request at ffffffffffffffb0
PGD 9e6e067 P4D 9e6e067 PUD 9e70067 PMD 0 
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 10180 Comm: syz-executor.5 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:vsscanf+0x1c9/0x25a0 lib/vsprintf.c:2958
Code: 89 e9 48 c1 ea 03 4c 89 b4 24 80 00 00 00 83 e1 07 41 0f b6 45 00 42 0f b6 14 3a 4d 89 f4 38 ca 7f 08 84 d2 0f 85 f7 17 00 00 <0f> b6 5d 00 89 c7 88 44 24 08 89 de e8 66 1a 72 f9 0f b6 44 24 08
RSP: 0018:ffff88809fbcea68 EFLAGS: 00010246
RAX: 0000000000000076 RBX: 0000000000000076 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff87f06b87 RDI: 0000000000000001
RBP: ffffffffffffffb0 R08: 0000000000000010 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff88801450cd81
R13: ffff88801450cd80 R14: ffff88801450cd81 R15: dffffc0000000000
FS:  00007fea61f1d700(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffb0 CR3: 000000009f173000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 sscanf+0xbb/0xf0 lib/vsprintf.c:3212
 __dev_alloc_name net/core/dev.c:1081 [inline]
 dev_alloc_name_ns+0x1c4/0x440 net/core/dev.c:1115
 dev_get_valid_name+0x67/0xe0 net/core/dev.c:1150
 register_netdevice+0x267/0x10f0 net/core/dev.c:8654
 veth_newlink+0x3eb/0x930 drivers/net/veth.c:1142
 rtnl_newlink+0x1030/0x15c0 net/core/rtnetlink.c:3141
 rtnetlink_rcv_msg+0x453/0xb80 net/core/rtnetlink.c:4782
 netlink_rcv_skb+0x160/0x440 net/netlink/af_netlink.c:2463
 netlink_unicast_kernel net/netlink/af_netlink.c:1325 [inline]
 netlink_unicast+0x4d5/0x690 net/netlink/af_netlink.c:1351
 netlink_sendmsg+0x6c3/0xc50 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0xc3/0x120 net/socket.c:661
 ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2227
 __sys_sendmsg net/socket.c:2265 [inline]
 __do_sys_sendmsg net/socket.c:2274 [inline]
 __se_sys_sendmsg net/socket.c:2272 [inline]
 __x64_sys_sendmsg+0x132/0x220 net/socket.c:2272
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fea635a80e9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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:00007fea61f1d168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fea636baf60 RCX: 00007fea635a80e9
RDX: 0000000000000000 RSI: 0000000020000040 RDI: 0000000000000005
RBP: 00007fea6360208d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffdff8b236f R14: 00007fea61f1d300 R15: 0000000000022000
Modules linked in:
CR2: ffffffffffffffb0
---[ end trace a81d2869f8f1bf63 ]---
RIP: 0010:vsscanf+0x1c9/0x25a0 lib/vsprintf.c:2958
Code: 89 e9 48 c1 ea 03 4c 89 b4 24 80 00 00 00 83 e1 07 41 0f b6 45 00 42 0f b6 14 3a 4d 89 f4 38 ca 7f 08 84 d2 0f 85 f7 17 00 00 <0f> b6 5d 00 89 c7 88 44 24 08 89 de e8 66 1a 72 f9 0f b6 44 24 08
RSP: 0018:ffff88809fbcea68 EFLAGS: 00010246
RAX: 0000000000000076 RBX: 0000000000000076 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff87f06b87 RDI: 0000000000000001
RBP: ffffffffffffffb0 R08: 0000000000000010 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff88801450cd81
R13: ffff88801450cd80 R14: ffff88801450cd81 R15: dffffc0000000000
FS:  00007fea61f1d700(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffb0 CR3: 000000009f173000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	89 e9                	mov    %ebp,%ecx
   2:	48 c1 ea 03          	shr    $0x3,%rdx
   6:	4c 89 b4 24 80 00 00 	mov    %r14,0x80(%rsp)
   d:	00
   e:	83 e1 07             	and    $0x7,%ecx
  11:	41 0f b6 45 00       	movzbl 0x0(%r13),%eax
  16:	42 0f b6 14 3a       	movzbl (%rdx,%r15,1),%edx
  1b:	4d 89 f4             	mov    %r14,%r12
  1e:	38 ca                	cmp    %cl,%dl
  20:	7f 08                	jg     0x2a
  22:	84 d2                	test   %dl,%dl
  24:	0f 85 f7 17 00 00    	jne    0x1821
* 2a:	0f b6 5d 00          	movzbl 0x0(%rbp),%ebx <-- trapping instruction
  2e:	89 c7                	mov    %eax,%edi
  30:	88 44 24 08          	mov    %al,0x8(%rsp)
  34:	89 de                	mov    %ebx,%esi
  36:	e8 66 1a 72 f9       	callq  0xf9721aa1
  3b:	0f b6 44 24 08       	movzbl 0x8(%rsp),%eax

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/04/24 19:55 linux-4.19.y 3f8a27f9e27b 131df97d .config console log report info ci2-linux-4-19 BUG: unable to handle kernel paging request in vsscanf
* Struck through repros no longer work on HEAD.