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general protection fault in fib_lookup_good_nhc

Status: closed as invalid on 2025/06/04 11:51
Subsystems: net
[Documentation on labels]
First crash: 83d, last: 83d
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 general protection fault in fib_lookup_good_nhc 2 6 4d16h 26d 0/3 upstream: reported on 2025/07/01 19:21
upstream Internal error in fib_lookup_good_nhc net 2 1 799d 799d 0/29 auto-obsoleted due to no activity on 2023/08/18 23:40

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000021: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000108-0x000000000000010f]
CPU: 0 UID: 0 PID: 12 Comm: kworker/u8:0 Not tainted 6.15.0-rc5-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:read_pnet include/net/net_namespace.h:409 [inline]
RIP: 0010:dev_net include/linux/netdevice.h:2708 [inline]
RIP: 0010:ip_ignore_linkdown include/linux/inetdevice.h:272 [inline]
RIP: 0010:fib_lookup_good_nhc+0x12d/0x3d0 net/ipv4/fib_trie.c:1408
Code: 74 08 4c 89 e7 e8 53 22 3d f8 41 bd 08 01 00 00 4d 03 2c 24 e8 b4 8b 71 01 4c 89 e8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 ef e8 25 22 3d f8 41 be f0 06 00 00 4d 03
RSP: 0018:ffffc90000007208 EFLAGS: 00010216
RAX: 0000000000000021 RBX: ffff8880594f8c80 RCX: dffffc0000000000
RDX: 0000000000000100 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffff8880594f8c97 R08: ffffc9000000742f R09: ffffc90000007400
R10: dffffc0000000000 R11: fffff52000000e86 R12: ffff88802850e800
R13: 0000000000000108 R14: 0000000000000001 R15: 1ffff1100b29f192
FS:  0000000000000000(0000) GS:ffff8881260cb000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c29436e CR3: 0000000030918000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 fib_table_lookup+0x964/0x16e0 net/ipv4/fib_trie.c:1594
 __ip_dev_find+0x288/0x4e0 net/ipv4/devinet.c:160
 ip_route_output_key_hash_rcu+0x1f9/0x2330 net/ipv4/route.c:2747
 ip_route_output_key_hash+0x1b9/0x2e0 net/ipv4/route.c:2683
 __ip_route_output_key include/net/route.h:169 [inline]
 ip_route_output_flow+0x2a/0x150 net/ipv4/route.c:2911
 inet_sk_rebuild_header+0x91a/0x1cc0 net/ipv4/af_inet.c:1322
 __tcp_retransmit_skb+0x262/0x1530 net/ipv4/tcp_output.c:3358
 tcp_retransmit_skb+0x33/0x440 net/ipv4/tcp_output.c:3458
 tcp_retransmit_timer+0x18ba/0x3200 net/ipv4/tcp_timer.c:627
 tcp_write_timer+0x162/0x2e0 net/ipv4/tcp_timer.c:738
 call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1789
 expire_timers kernel/time/timer.c:1840 [inline]
 __run_timers kernel/time/timer.c:2414 [inline]
 __run_timer_base+0x61a/0x860 kernel/time/timer.c:2426
 run_timer_base kernel/time/timer.c:2435 [inline]
 run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2445
 handle_softirqs+0x286/0x870 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:debug_check_no_locks_freed+0xec/0x1c0 kernel/locking/lockdep.c:6721
Code: c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 0f 85 bb 00 00 00 41 f7 c5 00 02 00 00 74 01 fb 65 48 8b 05 f4 09 d7 10 <48> 3b 44 24 08 0f 85 b5 00 00 00 48 83 c4 10 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc900001178e8 EFLAGS: 00000206
RAX: 1817bc10ae47a200 RBX: ffff88801b2fda00 RCX: ffff888030990901
RDX: 0000000000000000 RSI: ffff888030e7f000 RDI: ffff888030e7e000
RBP: 0000000000212008 R08: 0000000000000000 R09: 1ffffffff1efdb2e
R10: dffffc0000000000 R11: fffffbfff1efdb2f R12: ffff88801a042140
R13: 0000000000000202 R14: ffff88801b2fe590 R15: 0000000000000004
 slab_free_hook mm/slub.c:2308 [inline]
 slab_free mm/slub.c:4642 [inline]
 kfree+0x102/0x440 mm/slub.c:4841
 skb_kfree_head net/core/skbuff.c:1058 [inline]
 skb_free_head net/core/skbuff.c:1070 [inline]
 skb_release_data+0x69a/0x890 net/core/skbuff.c:1097
 skb_release_all net/core/skbuff.c:1162 [inline]
 __kfree_skb net/core/skbuff.c:1176 [inline]
 consume_skb+0x9e/0xf0 net/core/skbuff.c:1408
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline]
 nsim_dev_trap_report_work+0x7cf/0xb80 drivers/net/netdevsim/dev.c:851
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xade/0x17a0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
 kthread+0x711/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x4e/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:read_pnet include/net/net_namespace.h:409 [inline]
RIP: 0010:dev_net include/linux/netdevice.h:2708 [inline]
RIP: 0010:ip_ignore_linkdown include/linux/inetdevice.h:272 [inline]
RIP: 0010:fib_lookup_good_nhc+0x12d/0x3d0 net/ipv4/fib_trie.c:1408
Code: 74 08 4c 89 e7 e8 53 22 3d f8 41 bd 08 01 00 00 4d 03 2c 24 e8 b4 8b 71 01 4c 89 e8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 ef e8 25 22 3d f8 41 be f0 06 00 00 4d 03
RSP: 0018:ffffc90000007208 EFLAGS: 00010216
RAX: 0000000000000021 RBX: ffff8880594f8c80 RCX: dffffc0000000000
RDX: 0000000000000100 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffff8880594f8c97 R08: ffffc9000000742f R09: ffffc90000007400
R10: dffffc0000000000 R11: fffff52000000e86 R12: ffff88802850e800
R13: 0000000000000108 R14: 0000000000000001 R15: 1ffff1100b29f192
FS:  0000000000000000(0000) GS:ffff8881260cb000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c29436e CR3: 0000000030918000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess):
   0:	74 08                	je     0xa
   2:	4c 89 e7             	mov    %r12,%rdi
   5:	e8 53 22 3d f8       	call   0xf83d225d
   a:	41 bd 08 01 00 00    	mov    $0x108,%r13d
  10:	4d 03 2c 24          	add    (%r12),%r13
  14:	e8 b4 8b 71 01       	call   0x1718bcd
  19:	4c 89 e8             	mov    %r13,%rax
  1c:	48 c1 e8 03          	shr    $0x3,%rax
  20:	48 b9 00 00 00 00 00 	movabs $0xdffffc0000000000,%rcx
  27:	fc ff df
* 2a:	80 3c 08 00          	cmpb   $0x0,(%rax,%rcx,1) <-- trapping instruction
  2e:	74 08                	je     0x38
  30:	4c 89 ef             	mov    %r13,%rdi
  33:	e8 25 22 3d f8       	call   0xf83d225d
  38:	41 be f0 06 00 00    	mov    $0x6f0,%r14d
  3e:	4d                   	rex.WRB
  3f:	03                   	.byte 0x3

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/05 22:41 upstream 92a09c47464d 6ca47dd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root general protection fault in fib_lookup_good_nhc
* Struck through repros no longer work on HEAD.