syzbot


general protection fault in tcindex_set_parms

Status: fixed on 2023/06/08 14:41
Subsystems: net
[Documentation on labels]
Fix commit: 42018a322bd4 net/sched: tcindex: search key must be 16 bits
First crash: 426d, last: 426d
Cause bisection: introduced by (bisect log) :
commit 565b4824c39fa335cba2028a09d7beb7112f3c9a
Author: Jiri Pirko <jiri@nvidia.com>
Date: Mon Feb 6 09:41:51 2023 +0000

  devlink: change port event netdev notifier from per-net to global

Crash: unregister_netdevice: waiting for DEV to become free (log)
Repro: C syz .config
  

Sample crash report:
Zero length message leads to an empty skb
general protection fault, probably for non-canonical address 0xdffffc0000000015: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x00000000000000a8-0x00000000000000af]
CPU: 0 PID: 5070 Comm: syz-executor456 Not tainted 6.2.0-rc7-syzkaller-00112-gc68f345b7c42 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023
RIP: 0010:tcindex_set_parms+0x1a6a/0x2990 net/sched/cls_tcindex.c:509
Code: 01 e9 e9 fe ff ff 4c 8b bd 28 fe ff ff e8 0e 57 7d f9 48 8d bb a8 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 94 0c 00 00 48 8b 85 f8 fd ff ff 48 8b 9b a8 00
RSP: 0018:ffffc90003d3ef88 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000015 RSI: ffffffff8803a102 RDI: 00000000000000a8
RBP: ffffc90003d3f1d8 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff88801e2b10a8
R13: dffffc0000000000 R14: 0000000000030000 R15: ffff888017b3be00
FS:  00005555569af300(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056041c6d2000 CR3: 000000002bfca000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 tcindex_change+0x1ea/0x320 net/sched/cls_tcindex.c:572
 tc_new_tfilter+0x96e/0x2220 net/sched/cls_api.c:2155
 rtnetlink_rcv_msg+0x959/0xca0 net/core/rtnetlink.c:6132
 netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2574
 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline]
 netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1365
 netlink_sendmsg+0x91b/0xe10 net/netlink/af_netlink.c:1942
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg+0xd3/0x120 net/socket.c:734
 ____sys_sendmsg+0x334/0x8c0 net/socket.c:2476
 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2530
 __sys_sendmmsg+0x18f/0x460 net/socket.c:2616
 __do_sys_sendmmsg net/socket.c:2645 [inline]
 __se_sys_sendmmsg net/socket.c:2642 [inline]
 __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2642
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fed411b7cd9
Code: 28 c3 e8 1a 15 00 00 66 2e 0f 1f 84 00 00 00 00 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd73b418c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007fed41225ed0 RCX: 00007fed411b7cd9
RDX: 04924924924926d3 RSI: 0000000020000200 RDI: 0000000000000005
RBP: 00007ffd73b418d8 R08: 00007fed41225e40 R09: 00007fed41225e40
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd73b418e0
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:tcindex_set_parms+0x1a6a/0x2990 net/sched/cls_tcindex.c:509
Code: 01 e9 e9 fe ff ff 4c 8b bd 28 fe ff ff e8 0e 57 7d f9 48 8d bb a8 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 94 0c 00 00 48 8b 85 f8 fd ff ff 48 8b 9b a8 00
RSP: 0018:ffffc90003d3ef88 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000015 RSI: ffffffff8803a102 RDI: 00000000000000a8
RBP: ffffc90003d3f1d8 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff88801e2b10a8
R13: dffffc0000000000 R14: 0000000000030000 R15: ffff888017b3be00
FS:  00005555569af300(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000976528 CR3: 000000002bfca000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	01 e9                	add    %ebp,%ecx
   2:	e9 fe ff ff 4c       	jmpq   0x4d000005
   7:	8b bd 28 fe ff ff    	mov    -0x1d8(%rbp),%edi
   d:	e8 0e 57 7d f9       	callq  0xf97d5720
  12:	48 8d bb a8 00 00 00 	lea    0xa8(%rbx),%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:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1) <-- trapping instruction
  2e:	0f 85 94 0c 00 00    	jne    0xcc8
  34:	48 8b 85 f8 fd ff ff 	mov    -0x208(%rbp),%rax
  3b:	48                   	rex.W
  3c:	8b                   	.byte 0x8b
  3d:	9b                   	fwait
  3e:	a8 00                	test   $0x0,%al

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/02/13 15:04 net-old c68f345b7c42 4d66ad72 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce general protection fault in tcindex_set_parms
2023/02/13 14:33 net-old c68f345b7c42 4d66ad72 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce general protection fault in tcindex_set_parms
* Struck through repros no longer work on HEAD.