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general protection fault in ip6_create_rt_rcu (3)

Status: closed as invalid on 2026/04/08 13:13
Subsystems: net
[Documentation on labels]
First crash: 47d, last: 47d
Similar bugs (4)
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 339d 339d 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 197d 197d 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 346d 351d 0/29 auto-obsoleted due to no activity on 2025/08/14 23:11
upstream general protection fault in ip6_create_rt_rcu (2) net 2 1 129d 129d 0/29 closed as invalid on 2026/01/13 16:48

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 UID: 0 PID: 21739 Comm: syz.8.4347 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:ip6_create_rt_rcu+0x8f/0x5a0 net/ipv6/route.c:1227
Code: 87 b9 cf f7 48 89 e8 48 c1 e8 03 80 3c 18 00 0f 85 ce 04 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 5d 00 48 89 da 48 c1 ea 03 <80> 3c 02 00 0f 85 a2 04 00 00 48 8d 7d 08 4c 8b 3b 48 b8 00 00 00
RSP: 0018:ffffc90005adec30 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc90032a93000
RDX: 0000000000000000 RSI: ffffffff8a38e539 RDI: ffffc90005aded88
RBP: ffffc90005aded88 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000200 R11: 0000000000000000 R12: dffffc0000000000
R13: 1ffff92000b5bd88 R14: 0000000000000000 R15: 0000000000000200
FS:  00007f2e4a7a26c0(0000) GS:ffff8880d6344000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2e49a4eaeb CR3: 0000000000a81000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 ip6_pol_route_lookup+0xc90/0x1fa0 net/ipv6/route.c:1293
 pol_lookup_func include/net/ip6_fib.h:617 [inline]
 __fib6_rule_action net/ipv6/fib6_rules.c:237 [inline]
 fib6_rule_action+0x7a0/0x910 net/ipv6/fib6_rules.c:275
 fib_rules_lookup+0x418/0x1080 net/core/fib_rules.c:339
 fib6_rule_lookup+0x18b/0x720 net/ipv6/fib6_rules.c:112
 rt6_lookup+0x175/0x230 net/ipv6/route.c:1327
 geneve_link_config.part.0+0x14b/0x5b0 drivers/net/geneve.c:2121
 geneve_link_config include/net/rtnetlink.h:95 [inline]
 geneve_newlink+0x334/0x390 drivers/net/geneve.c:2164
 rtnl_newlink_create net/core/rtnetlink.c:3840 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3957 [inline]
 rtnl_newlink+0x1494/0x2380 net/core/rtnetlink.c:4072
 rtnetlink_rcv_msg+0x95e/0xe90 net/core/rtnetlink.c:6958
 netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2550
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg net/socket.c:742 [inline]
 ____sys_sendmsg+0xa54/0xc30 net/socket.c:2592
 ___sys_sendmsg+0x190/0x1e0 net/socket.c:2646
 __sys_sendmsg+0x170/0x220 net/socket.c:2678
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2e4999c799
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2e4a7a2028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f2e49c15fa0 RCX: 00007f2e4999c799
RDX: 0000000000000000 RSI: 0000200000000240 RDI: 0000000000000006
RBP: 00007f2e49a32bd9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2e49c16038 R14: 00007f2e49c15fa0 R15: 00007ffcec6c0ba8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ip6_create_rt_rcu+0x8f/0x5a0 net/ipv6/route.c:1227
Code: 87 b9 cf f7 48 89 e8 48 c1 e8 03 80 3c 18 00 0f 85 ce 04 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 5d 00 48 89 da 48 c1 ea 03 <80> 3c 02 00 0f 85 a2 04 00 00 48 8d 7d 08 4c 8b 3b 48 b8 00 00 00
RSP: 0018:ffffc90005adec30 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc90032a93000
RDX: 0000000000000000 RSI: ffffffff8a38e539 RDI: ffffc90005aded88
RBP: ffffc90005aded88 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000200 R11: 0000000000000000 R12: dffffc0000000000
R13: 1ffff92000b5bd88 R14: 0000000000000000 R15: 0000000000000200
FS:  00007f2e4a7a26c0(0000) GS:ffff8880d6344000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2e49a4eaeb CR3: 0000000000a81000 CR4: 0000000000352ef0
----------------
Code disassembly (best guess):
   0:	87 b9 cf f7 48 89    	xchg   %edi,-0x76b70831(%rcx)
   6:	e8 48 c1 e8 03       	call   0x3e8c153
   b:	80 3c 18 00          	cmpb   $0x0,(%rax,%rbx,1)
   f:	0f 85 ce 04 00 00    	jne    0x4e3
  15:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  1c:	fc ff df
  1f:	48 8b 5d 00          	mov    0x0(%rbp),%rbx
  23:	48 89 da             	mov    %rbx,%rdx
  26:	48 c1 ea 03          	shr    $0x3,%rdx
* 2a:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1) <-- trapping instruction
  2e:	0f 85 a2 04 00 00    	jne    0x4d6
  34:	48 8d 7d 08          	lea    0x8(%rbp),%rdi
  38:	4c 8b 3b             	mov    (%rbx),%r15
  3b:	48                   	rex.W
  3c:	b8                   	.byte 0xb8
  3d:	00 00                	add    %al,(%rax)

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/01 13:29 upstream eb71ab2bf722 43249bac .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in ip6_create_rt_rcu
* Struck through repros no longer work on HEAD.