syzbot


general protection fault in em_u32_match

Status: auto-closed as invalid on 2021/12/29 15:06
Reported-by: syzbot+3b895505ea28dc6f5f78@syzkaller.appspotmail.com
First crash: 1054d, last: 1054d
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 general protection fault in em_u32_match (2) C error 1 554d 554d 0/1 upstream: reported C repro on 2023/01/14 00:52
upstream general protection fault in em_u32_match net 1 1446d 1446d 0/27 auto-closed as invalid on 2020/11/02 22:53
linux-4.14 general protection fault in em_u32_match C 1 529d 560d 0/1 upstream: reported C repro on 2023/01/08 12:41
upstream BUG: unable to handle kernel NULL pointer dereference in em_u32_match net C 2 568d 624d 22/27 fixed on 2023/02/24 13:50

Sample crash report:
TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies.  Check SNMP counters.
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: 12009 Comm: syz-executor.4 Not tainted 4.19.205-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:em_u32_match+0x156/0x300 net/sched/em_u32.c:33
Code: 9c 01 00 00 41 23 5c 24 0c 48 63 db 4c 01 fb e8 30 ff c2 fa 49 8d 7c 24 08 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 08 84 d2 0f 85 21
RSP: 0018:ffff8880618c6e48 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff88809636cd10 RCX: ffffc9000e647000
RDX: 0000000000000001 RSI: ffffffff869f9390 RDI: 0000000000000008
RBP: ffff8880a53278c0 R08: 0000000000000000 R09: 0000000000000002
R10: 0000000000000004 R11: 0000000000074071 R12: 0000000000000000
R13: 0000000000000000 R14: ffff88809636cd00 R15: dffffc0000000000
FS:  00007f11f1d81700(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4f73fff718 CR3: 00000000664c8000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies.  Check SNMP counters.
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 tcf_em_match net/sched/ematch.c:496 [inline]
 __tcf_em_tree_match+0x14a/0x530 net/sched/ematch.c:522
 tcf_em_tree_match include/net/pkt_cls.h:531 [inline]
 basic_classify+0x1c0/0x2b0 net/sched/cls_basic.c:49
 tcf_classify+0x120/0x3c0 net/sched/cls_api.c:979
 hfsc_classify net/sched/sch_hfsc.c:1141 [inline]
 hfsc_enqueue+0x31a/0x10a0 net/sched/sch_hfsc.c:1545
 __dev_xmit_skb net/core/dev.c:3494 [inline]
 __dev_queue_xmit+0x140a/0x2e00 net/core/dev.c:3807
hfsplus: unable to find HFS+ superblock
 neigh_resolve_output+0x55a/0x910 net/core/neighbour.c:1374
 neigh_output include/net/neighbour.h:501 [inline]
 ip_finish_output2+0xd76/0x15a0 net/ipv4/ip_output.c:230
 ip_do_fragment+0x1e1a/0x2620 net/ipv4/ip_output.c:680
 ip_fragment.constprop.0+0x174/0x240 net/ipv4/ip_output.c:551
 ip_finish_output+0xa35/0x10b0 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:278 [inline]
 ip_mc_output+0x268/0xec0 net/ipv4/ip_output.c:391
 dst_output include/net/dst.h:455 [inline]
 ip_local_out+0xaf/0x170 net/ipv4/ip_output.c:125
 ip_send_skb net/ipv4/ip_output.c:1451 [inline]
 ip_push_pending_frames+0x8b/0x140 net/ipv4/ip_output.c:1471
 raw_sendmsg+0x1e9d/0x29e0 net/ipv4/raw.c:677
 inet_sendmsg+0x132/0x5a0 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0xc3/0x120 net/socket.c:661
 sock_no_sendpage+0xf5/0x140 net/core/sock.c:2668
 inet_sendpage+0x465/0x650 net/ipv4/af_inet.c:816
 kernel_sendpage net/socket.c:3581 [inline]
 sock_sendpage+0xdf/0x140 net/socket.c:912
 pipe_to_sendpage+0x268/0x330 fs/splice.c:452
 splice_from_pipe_feed fs/splice.c:503 [inline]
 __splice_from_pipe+0x389/0x800 fs/splice.c:627
 splice_from_pipe fs/splice.c:662 [inline]
 generic_splice_sendpage+0xd4/0x140 fs/splice.c:833
 do_splice_from fs/splice.c:852 [inline]
 do_splice fs/splice.c:1154 [inline]
 __do_sys_splice fs/splice.c:1428 [inline]
 __se_sys_splice+0xfe7/0x16d0 fs/splice.c:1408
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4665f9
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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f11f1d81188 EFLAGS: 00000246 ORIG_RAX: 0000000000000113
RAX: ffffffffffffffda RBX: 000000000056c038 RCX: 00000000004665f9
RDX: 0000000000000005 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00000000004bfcc4 R08: 0000000000019403 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c038
R13: 00007ffc1369e29f R14: 00007f11f1d81300 R15: 0000000000022000
Modules linked in:
---[ end trace c7533c8ec228fb52 ]---
RIP: 0010:em_u32_match+0x156/0x300 net/sched/em_u32.c:33
Code: 9c 01 00 00 41 23 5c 24 0c 48 63 db 4c 01 fb e8 30 ff c2 fa 49 8d 7c 24 08 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 08 84 d2 0f 85 21
RSP: 0018:ffff8880618c6e48 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff88809636cd10 RCX: ffffc9000e647000
RDX: 0000000000000001 RSI: ffffffff869f9390 RDI: 0000000000000008
RBP: ffff8880a53278c0 R08: 0000000000000000 R09: 0000000000000002
R10: 0000000000000004 R11: 0000000000074071 R12: 0000000000000000
R13: 0000000000000000 R14: ffff88809636cd00 R15: dffffc0000000000
FS:  00007f11f1d81700(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4f73fff718 CR3: 00000000664c8000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	9c                   	pushfq
   1:	01 00                	add    %eax,(%rax)
   3:	00 41 23             	add    %al,0x23(%rcx)
   6:	5c                   	pop    %rsp
   7:	24 0c                	and    $0xc,%al
   9:	48 63 db             	movslq %ebx,%rbx
   c:	4c 01 fb             	add    %r15,%rbx
   f:	e8 30 ff c2 fa       	callq  0xfac2ff44
  14:	49 8d 7c 24 08       	lea    0x8(%r12),%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 08                	jl     0x43
  3b:	84 d2                	test   %dl,%dl
  3d:	0f                   	.byte 0xf
  3e:	85 21                	test   %esp,(%rcx)

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/08/31 15:05 linux-4.19.y e23d55af0e1f 7eb7e152 .config console log report info ci2-linux-4-19 general protection fault in em_u32_match
* Struck through repros no longer work on HEAD.