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WARNING in __skb_flow_dissect (5)

Status: closed as invalid on 2024/04/26 11:59
Subsystems: net
[Documentation on labels]
First crash: 843d, last: 843d
▶ ▼ Similar bugs (7)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in __skb_flow_dissect (6) net -1 1 804d 804d 27/29 fixed on 2024/08/14 19:57
linux-6.1 WARNING in __skb_flow_dissect -1 C error 33 1d22h 183d 0/3 upstream: reported C repro on 2026/01/17 07:47
upstream WARNING in __skb_flow_dissect net -1 syz 3 2839d 2840d 11/29 fixed on 2018/10/11 18:37
upstream WARNING in __skb_flow_dissect (7) net -1 275 187d 180d 29/29 fixed on 2026/05/06 16:40
linux-6.6 WARNING in __skb_flow_dissect origin:lts-only -1 C 17 17d 98d 0/2 upstream: reported C repro on 2026/04/13 06:50
upstream WARNING in __skb_flow_dissect (3) net -1 syz 224 2742d 2832d 11/29 fixed on 2019/03/06 07:43
upstream WARNING in __skb_flow_dissect (4) net -1 C error 6 1352d 1361d 22/29 fixed on 2023/02/24 13:50

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 1 PID: 4623 at net/core/flow_dissector.c:1096 __skb_flow_dissect+0xc73/0x7d00 net/core/flow_dissector.c:1096
Modules linked in:
CPU: 1 PID: 4623 Comm: syz-executor.3 Not tainted 6.8.0-syzkaller-05271-gf99c5f563c17 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
RIP: 0010:__skb_flow_dissect+0xc73/0x7d00 net/core/flow_dissector.c:1096
Code: 65 00 00 80 3d 67 9d 2d 06 01 0f 85 8a 65 00 00 e8 02 53 51 f8 e9 99 fa ff ff e8 f8 52 51 f8 e9 eb f9 ff ff e8 ee 52 51 f8 90 <0f> 0b 90 e9 de 03 00 00 e8 e0 52 51 f8 c6 05 32 9d 2d 06 01 48 c7
RSP: 0000:ffffc90000a07980 EFLAGS: 00010246
RAX: ffffffff89439d82 RBX: 0000000000000000 RCX: ffff888015b3bc00
RDX: 0000000000000301 RSI: 0000000000000000 RDI: ffff88807d7477f0
RBP: ffffc90000a07fa8 R08: ffffffff8943936d R09: 0000000000000000
R10: ffffc90000a08080 R11: fffff5200014101a R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff8f871d12 R15: ffffffff8f871d08
FS:  000055557e2c9480(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000220 CR3: 000000001daf6000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 skb_flow_dissect_flow_keys include/linux/skbuff.h:1546 [inline]
 ___skb_get_hash+0x55/0x800 net/core/flow_dissector.c:1791
 __skb_get_hash+0xbc/0x410 net/core/flow_dissector.c:1856
 skb_get_hash include/linux/skbuff.h:1588 [inline]
 nft_trace_init+0x1e5/0x440 net/netfilter/nf_tables_trace.c:320
 nft_do_chain+0x1c42/0x1da0 net/netfilter/nf_tables_core.c:268
 nft_do_chain_inet+0x418/0x6b0 net/netfilter/nft_chain_filter.c:161
 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
 nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626
 nf_hook include/linux/netfilter.h:269 [inline]
 __ip6_local_out+0x6fa/0x800 net/ipv6/output_core.c:143
 ip6_local_out+0x26/0x70 net/ipv6/output_core.c:153
 ip6tunnel_xmit include/net/ip6_tunnel.h:161 [inline]
 udp_tunnel6_xmit_skb+0x590/0x9d0 net/ipv6/ip6_udp_tunnel.c:111
 tipc_udp_xmit+0x6a3/0xa10 net/tipc/udp_media.c:217
 tipc_udp_send_msg+0x26b/0x3d0 net/tipc/udp_media.c:268
 tipc_bearer_xmit_skb+0x2f5/0x460 net/tipc/bearer.c:571
 tipc_disc_timeout+0x5ee/0x760 net/tipc/discover.c:338
 call_timer_fn+0x17e/0x600 kernel/time/timer.c:1792
 expire_timers kernel/time/timer.c:1843 [inline]
 __run_timers kernel/time/timer.c:2408 [inline]
 __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2419
 run_timer_base kernel/time/timer.c:2428 [inline]
 run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2438
 __do_softirq+0x2bc/0x943 kernel/softirq.c:554
 invoke_softirq kernel/softirq.c:428 [inline]
 __irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:645
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202
Code: 90 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 fa 16 f7 f5 48 89 df e8 b2 56 f8 f5 e8 2d 77 21 f6 fb bf 01 00 00 00 <e8> 42 43 ea f5 65 8b 05 93 25 89 74 85 c0 74 06 5b c3 cc cc cc cc
RSP: 0000:ffffc9000d7e7c50 EFLAGS: 00000282
RAX: 3483501b5e27f500 RBX: ffff88802a0fdc80 RCX: ffffffff944bf403
RDX: dffffc0000000000 RSI: ffffffff8baac220 RDI: 0000000000000001
RBP: ffffc9000d7e7d90 R08: ffffffff8f86ae6f R09: 1ffffffff1f0d5cd
R10: dffffc0000000000 R11: fffffbfff1f0d5ce R12: 1ffff1100541fbcb
R13: 0000000044000004 R14: 000000000000000b R15: ffff88802a0fde58
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 get_signal+0x156e/0x1850 kernel/signal.c:2910
 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop kernel/entry/common.c:105 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 irqentry_exit_to_user_mode+0x79/0x270 kernel/entry/common.c:225
 exc_page_fault+0x585/0x890 arch/x86/mm/fault.c:1566
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7fa1eb42c514
Code: c0 08 0f b7 c0 48 8b 54 24 10 66 89 02 e9 71 fd ff ff 48 8b 44 24 08 48 85 c0 0f 85 6c fe ff ff 48 8b 44 24 10 0f b6 54 24 18 <88> 10 e9 52 fd ff ff 48 8b 44 24 20 48 0b 44 24 28 75 31 48 8b 54
RSP: 002b:00007ffda1931040 EFLAGS: 00010246
RAX: 0000000020000220 RBX: 0000000000000001 RCX: 0000000000000000
RDX: 0000000000000085 RSI: 0000000000000000 RDI: 000055557e2c9360
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa1eb007cc0
R13: fffffffffffffffe R14: 00007fa1eb000000 R15: 00007fa1eb007cc8
 </TASK>
----------------
Code disassembly (best guess):
   0:	90                   	nop
   1:	f3 0f 1e fa          	endbr64
   5:	53                   	push   %rbx
   6:	48 89 fb             	mov    %rdi,%rbx
   9:	48 83 c7 18          	add    $0x18,%rdi
   d:	48 8b 74 24 08       	mov    0x8(%rsp),%rsi
  12:	e8 fa 16 f7 f5       	call   0xf5f71711
  17:	48 89 df             	mov    %rbx,%rdi
  1a:	e8 b2 56 f8 f5       	call   0xf5f856d1
  1f:	e8 2d 77 21 f6       	call   0xf6217751
  24:	fb                   	sti
  25:	bf 01 00 00 00       	mov    $0x1,%edi
* 2a:	e8 42 43 ea f5       	call   0xf5ea4371 <-- trapping instruction
  2f:	65 8b 05 93 25 89 74 	mov    %gs:0x74892593(%rip),%eax        # 0x748925c9
  36:	85 c0                	test   %eax,%eax
  38:	74 06                	je     0x40
  3a:	5b                   	pop    %rbx
  3b:	c3                   	ret
  3c:	cc                   	int3
  3d:	cc                   	int3
  3e:	cc                   	int3
  3f:	cc                   	int3

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/03/28 09:50 net f99c5f563c17 454571b6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in __skb_flow_dissect
* Struck through repros no longer work on HEAD.