syzbot


general protection fault in ip6_ins_rt

Status: upstream: reported on 2025/05/19 10:23
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+ce95bbc882771b5d81f7@syzkaller.appspotmail.com
First crash: 35d, last: 22d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [net?] general protection fault in ip6_ins_rt 0 (1) 2025/05/19 10:23

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]
CPU: 1 UID: 0 PID: 12 Comm: kworker/u8:0 Not tainted 6.15.0-syzkaller-02443-g015a99fa7665 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: ipv6_addrconf addrconf_dad_work
RIP: 0010:kasan_byte_accessible+0x12/0x30 mm/kasan/generic.c:199
Code: 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 48 c1 ef 03 48 b8 00 00 00 00 00 fc ff df <0f> b6 04 07 3c 08 0f 92 c0 c3 cc cc cc cc cc 66 66 66 66 66 66 2e
RSP: 0018:ffffc900001174c8 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: ffffffff8b6074d6 RCX: 5d5c78f8f18cfe00
RDX: 0000000000000000 RSI: ffffffff8b6074d6 RDI: 0000000000000006
RBP: ffffffff8a1507a2 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000015 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000030 R14: 0000000000000030 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff888125d91000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f50d5da4 CR3: 000000002916a000 CR4: 00000000003526f0
DR0: 0000040000000000 DR1: 000000000000064f DR2: 0000000000000006
DR3: 0000000000000006 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __kasan_check_byte+0x12/0x40 mm/kasan/common.c:556
 kasan_check_byte include/linux/kasan.h:399 [inline]
 lock_acquire+0x8d/0x360 kernel/locking/lockdep.c:5845
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
 _raw_spin_lock_bh+0x36/0x50 kernel/locking/spinlock.c:178
 spin_lock_bh include/linux/spinlock.h:356 [inline]
 __ip6_ins_rt net/ipv6/route.c:1350 [inline]
 ip6_ins_rt+0xb2/0x120 net/ipv6/route.c:1361
 __ipv6_ifa_notify+0x63f/0xac0 net/ipv6/addrconf.c:6286
 ipv6_ifa_notify net/ipv6/addrconf.c:6325 [inline]
 addrconf_dad_completed+0x180/0xd60 net/ipv6/addrconf.c:4324
 addrconf_dad_work+0xc36/0x14b0 net/ipv6/addrconf.c:-1
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
 kthread+0x711/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:kasan_byte_accessible+0x12/0x30 mm/kasan/generic.c:199
Code: 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 48 c1 ef 03 48 b8 00 00 00 00 00 fc ff df <0f> b6 04 07 3c 08 0f 92 c0 c3 cc cc cc cc cc 66 66 66 66 66 66 2e
RSP: 0018:ffffc900001174c8 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: ffffffff8b6074d6 RCX: 5d5c78f8f18cfe00
RDX: 0000000000000000 RSI: ffffffff8b6074d6 RDI: 0000000000000006
RBP: ffffffff8a1507a2 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000015 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000030 R14: 0000000000000030 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff888125d91000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f50d5da4 CR3: 000000002916a000 CR4: 00000000003526f0
DR0: 0000040000000000 DR1: 000000000000064f DR2: 0000000000000006
DR3: 0000000000000006 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	0f 1f 84 00 00 00 00 	nopl   0x0(%rax,%rax,1)
   7:	00
   8:	90                   	nop
   9:	90                   	nop
   a:	90                   	nop
   b:	90                   	nop
   c:	90                   	nop
   d:	90                   	nop
   e:	90                   	nop
   f:	90                   	nop
  10:	90                   	nop
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
  16:	90                   	nop
  17:	90                   	nop
  18:	66 0f 1f 00          	nopw   (%rax)
  1c:	48 c1 ef 03          	shr    $0x3,%rdi
  20:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  27:	fc ff df
* 2a:	0f b6 04 07          	movzbl (%rdi,%rax,1),%eax <-- trapping instruction
  2e:	3c 08                	cmp    $0x8,%al
  30:	0f 92 c0             	setb   %al
  33:	c3                   	ret
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	cc                   	int3
  38:	cc                   	int3
  39:	66                   	data16
  3a:	66                   	data16
  3b:	66                   	data16
  3c:	66                   	data16
  3d:	66                   	data16
  3e:	66                   	data16
  3f:	2e                   	cs

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/28 05:15 upstream 015a99fa7665 874a1386 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 general protection fault in ip6_ins_rt
2025/05/15 05:42 upstream c94d59a126cb d6b2ee52 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 general protection fault in ip6_ins_rt
* Struck through repros no longer work on HEAD.