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general protection fault in ip6_create_rt_rcu (2)

Status: closed as invalid on 2026/01/13 16:48
Subsystems: net
[Documentation on labels]
First crash: 36d, last: 36d
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-10 general protection fault in ip6_create_rt_rcu 2 1 246d 246d 0/2 auto-obsoleted due to no activity on 2025/08/11 02:40
android-5-10 general protection fault in ip6_create_rt_rcu (2) 2 1 104d 104d 0/2 auto-obsoleted due to no activity on 2025/12/31 12:46
upstream general protection fault in ip6_create_rt_rcu net 2 2 252d 258d 0/29 auto-obsoleted due to no activity on 2025/08/14 23:11

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 1 UID: 0 PID: 24990 Comm: syz.5.6108 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:ip6_create_rt_rcu+0x92/0x4c0 net/ipv6/route.c:1227
Code: 08 4a 89 04 21 e8 ce ae b5 f7 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 18 0e 1c f8 49 8b 1e 48 89 d8 48 c1 e8 03 <42> 80 3c 20 00 74 08 48 89 df e8 ff 0d 1c f8 48 8b 1b 4c 89 74 24
RSP: 0018:ffffc9000435f220 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000080000
RDX: ffffc900045d1000 RSI: 000000000000009b RDI: 000000000000009c
RBP: ffffc9000435f2d0 R08: ffffc9000435f24f R09: 0000000000000000
R10: ffffc9000435f240 R11: fffff5200086be4a R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffc9000435f3e0 R15: ffff8880557d8000
FS:  00007f8ba4df66c0(0000) GS:ffff888125f35000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c35a5ba CR3: 000000007b788000 CR4: 00000000003526f0
DR0: 0000000000000080 DR1: 0000000000000003 DR2: 0000000000000008
DR3: 0000000080000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ip6_pol_route_lookup+0xb0b/0xcd0 net/ipv6/route.c:1293
 pol_lookup_func include/net/ip6_fib.h:617 [inline]
 fib6_rule_lookup+0x62a/0x6f0 net/ipv6/fib6_rules.c:125
 rt6_lookup+0x119/0x1d0 net/ipv6/route.c:1327
 ip6_mc_find_dev+0xf4/0x300 net/ipv6/mcast.c:181
 __ipv6_sock_mc_join+0x47c/0x770 net/ipv6/mcast.c:223
 do_ipv6_mcast_group_source+0x306/0x3e0 net/ipv6/ipv6_sockglue.c:173
 do_ipv6_setsockopt+0x15f9/0x2eb0 net/ipv6/ipv6_sockglue.c:919
 ipv6_setsockopt+0x59/0x170 net/ipv6/ipv6_sockglue.c:973
 do_sock_setsockopt+0x17c/0x1b0 net/socket.c:2337
 __sys_setsockopt net/socket.c:2362 [inline]
 __do_sys_setsockopt net/socket.c:2368 [inline]
 __se_sys_setsockopt net/socket.c:2365 [inline]
 __x64_sys_setsockopt+0x13f/0x1b0 net/socket.c:2365
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8ba6b8f749
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8ba4df6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007f8ba6de5fa0 RCX: 00007f8ba6b8f749
RDX: 000000000000002e RSI: 0000000000000029 RDI: 0000000000000006
RBP: 00007f8ba6c13f91 R08: 0000000000000108 R09: 0000000000000000
R10: 0000200000000200 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8ba6de6038 R14: 00007f8ba6de5fa0 R15: 00007ffc5306f7b8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ip6_create_rt_rcu+0x92/0x4c0 net/ipv6/route.c:1227
Code: 08 4a 89 04 21 e8 ce ae b5 f7 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 18 0e 1c f8 49 8b 1e 48 89 d8 48 c1 e8 03 <42> 80 3c 20 00 74 08 48 89 df e8 ff 0d 1c f8 48 8b 1b 4c 89 74 24
RSP: 0018:ffffc9000435f220 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000080000
RDX: ffffc900045d1000 RSI: 000000000000009b RDI: 000000000000009c
RBP: ffffc9000435f2d0 R08: ffffc9000435f24f R09: 0000000000000000
R10: ffffc9000435f240 R11: fffff5200086be4a R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffc9000435f3e0 R15: ffff8880557d8000
FS:  00007f8ba4df66c0(0000) GS:ffff888125e35000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9a209a8d58 CR3: 000000007b788000 CR4: 00000000003526f0
DR0: 0000000000000080 DR1: 0000000000000003 DR2: 0000000000000008
DR3: 0000000080000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	08 4a 89             	or     %cl,-0x77(%rdx)
   3:	04 21                	add    $0x21,%al
   5:	e8 ce ae b5 f7       	call   0xf7b5aed8
   a:	4c 89 f0             	mov    %r14,%rax
   d:	48 c1 e8 03          	shr    $0x3,%rax
  11:	42 80 3c 20 00       	cmpb   $0x0,(%rax,%r12,1)
  16:	74 08                	je     0x20
  18:	4c 89 f7             	mov    %r14,%rdi
  1b:	e8 18 0e 1c f8       	call   0xf81c0e38
  20:	49 8b 1e             	mov    (%r14),%rbx
  23:	48 89 d8             	mov    %rbx,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 20 00       	cmpb   $0x0,(%rax,%r12,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	48 89 df             	mov    %rbx,%rdi
  34:	e8 ff 0d 1c f8       	call   0xf81c0e38
  39:	48 8b 1b             	mov    (%rbx),%rbx
  3c:	4c                   	rex.WR
  3d:	89                   	.byte 0x89
  3e:	74 24                	je     0x64

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/09 04:31 linux-next c75caf76ed86 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root general protection fault in ip6_create_rt_rcu
* Struck through repros no longer work on HEAD.