syzbot
general protection fault in dst_dev_put (8)
Status: closed as invalid on 2026/09/11 15:35
Subsystems:
net
Labels:
prio:high
[Documentation on labels]
First crash: 95d, last: 32d
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: 23 Comm: ksoftirqd/1 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:dst_dev_put+0x27/0x2b0 net/core/dst.c:147
Code: 90 90 90 f3 0f 1e fa 55 41 57 41 56 41 55 41 54 53 48 89 fb 49 bc 00 00 00 00 00 fc ff df e8 b0 4a 22 f8 49 89 dd 49 c1 ed 03 <43> 80 7c 25 00 00 74 08 48 89 df e8 c9 e3 8f f8 4c 8b 33 48 8d 7b
RSP: 0018:ffffc900001d7aa0 EFLAGS: 00010246
RAX: ffffffff89a4b7e0 RBX: 0000000000000001 RCX: ffff88801e2a8000
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 1ffffffff1c9ebde R08: ffff8880525ac6fb R09: 1ffff1100a4b58df
R10: dffffc0000000000 R11: ffffed100a4b58e0 R12: dffffc0000000000
R13: 0000000000000000 R14: 0000607edacd9be0 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125058000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9f4215e080 CR3: 000000000e946000 CR4: 00000000003526f0
Call Trace:
<TASK>
rt_fibinfo_free_cpus net/ipv4/fib_semantics.c:195 [inline]
fib_nh_common_release+0x1ed/0x420 net/ipv4/fib_semantics.c:206
fib_nh_release net/ipv4/fib_semantics.c:217 [inline]
free_fib_info_rcu+0xe3/0x2f0 net/ipv4/fib_semantics.c:229
rcu_do_batch kernel/rcu/tree.c:2645 [inline]
rcu_core+0x78b/0x10a0 kernel/rcu/tree.c:2897
handle_softirqs+0x225/0x840 kernel/softirq.c:622
run_ksoftirqd+0x36/0x60 kernel/softirq.c:1076
smpboot_thread_fn+0x57c/0xa80 kernel/smpboot.c:160
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:dst_dev_put+0x27/0x2b0 net/core/dst.c:147
Code: 90 90 90 f3 0f 1e fa 55 41 57 41 56 41 55 41 54 53 48 89 fb 49 bc 00 00 00 00 00 fc ff df e8 b0 4a 22 f8 49 89 dd 49 c1 ed 03 <43> 80 7c 25 00 00 74 08 48 89 df e8 c9 e3 8f f8 4c 8b 33 48 8d 7b
RSP: 0018:ffffc900001d7aa0 EFLAGS: 00010246
RAX: ffffffff89a4b7e0 RBX: 0000000000000001 RCX: ffff88801e2a8000
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 1ffffffff1c9ebde R08: ffff8880525ac6fb R09: 1ffff1100a4b58df
R10: dffffc0000000000 R11: ffffed100a4b58e0 R12: dffffc0000000000
R13: 0000000000000000 R14: 0000607edacd9be0 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125058000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9f4215e080 CR3: 000000000e946000 CR4: 00000000003526f0
----------------
Code disassembly (best guess):
0: 90 nop
1: 90 nop
2: 90 nop
3: f3 0f 1e fa endbr64
7: 55 push %rbp
8: 41 57 push %r15
a: 41 56 push %r14
c: 41 55 push %r13
e: 41 54 push %r12
10: 53 push %rbx
11: 48 89 fb mov %rdi,%rbx
14: 49 bc 00 00 00 00 00 movabs $0xdffffc0000000000,%r12
1b: fc ff df
1e: e8 b0 4a 22 f8 call 0xf8224ad3
23: 49 89 dd mov %rbx,%r13
26: 49 c1 ed 03 shr $0x3,%r13
* 2a: 43 80 7c 25 00 00 cmpb $0x0,0x0(%r13,%r12,1) <-- trapping instruction
30: 74 08 je 0x3a
32: 48 89 df mov %rbx,%rdi
35: e8 c9 e3 8f f8 call 0xf88fe403
3a: 4c 8b 33 mov (%rbx),%r14
3d: 48 rex.W
3e: 8d .byte 0x8d
3f: 7b .byte 0x7b
* Struck through repros no longer work on HEAD.