general protection fault in dst_dev_put

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3f8a27f9e27b Linux 4.19.211
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=168706a1880000
kernel config: https://syzkaller.appspot.com/x/.config?x=9b9277b418617afe
dashboard link: https://syzkaller.appspot.com/bug?extid=01483da841b991ce1ca1
compiler: gcc version 10.2.1 20210110 (Debian 10.2.1-6)

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/98c0bdb4abb3/disk-3f8a27f9.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ea228ff02669/vmlinux-3f8a27f9.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+01483d...@syzkaller.appspotmail.com

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 18 Comm: ksoftirqd/1 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
RIP: 0010:dst_dev_put+0x1f/0x280 net/core/dst.c:168
Code: 66 66 2e 0f 1f 84 00 00 00 00 00 41 55 41 54 55 53 48 89 fb e8 12 c8 e9 fa 48 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f 85 e5 01 00 00 48 8d 7b 3a 48 8b 2b 48 b8 00 00 00
RSP: 0018:ffff8880b5acfc50 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 0000000000000001 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8678bd5e RDI: 0000000000000001
RBP: 0000000000000000 R08: 0000000051196c60 R09: 0000000000000000
R10: 0000000000000004 R11: 0000000000000000 R12: 0000000000000007
R13: 0000607f458ff910 R14: 0000000000000001 R15: 0000607f458ff910
FS: 0000000000000000(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005639ce414030 CR3: 00000000a0e1f000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
rt_fibinfo_free_cpus net/ipv4/fib_semantics.c:200 [inline]
free_fib_info_rcu+0x369/0x570 net/ipv4/fib_semantics.c:218
__rcu_reclaim kernel/rcu/rcu.h:236 [inline]
rcu_do_batch kernel/rcu/tree.c:2584 [inline]
invoke_rcu_callbacks kernel/rcu/tree.c:2897 [inline]
__rcu_process_callbacks kernel/rcu/tree.c:2864 [inline]
rcu_process_callbacks+0x8ff/0x18b0 kernel/rcu/tree.c:2881
__do_softirq+0x265/0x980 kernel/softirq.c:292
run_ksoftirqd+0x57/0x110 kernel/softirq.c:653
smpboot_thread_fn+0x655/0x9e0 kernel/smpboot.c:164
kthread+0x33f/0x460 kernel/kthread.c:259
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Modules linked in:
---[ end trace 9beba5859b228df4 ]---
RIP: 0010:dst_dev_put+0x1f/0x280 net/core/dst.c:168
Code: 66 66 2e 0f 1f 84 00 00 00 00 00 41 55 41 54 55 53 48 89 fb e8 12 c8 e9 fa 48 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f 85 e5 01 00 00 48 8d 7b 3a 48 8b 2b 48 b8 00 00 00
RSP: 0018:ffff8880b5acfc50 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 0000000000000001 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8678bd5e RDI: 0000000000000001
RBP: 0000000000000000 R08: 0000000051196c60 R09: 0000000000000000
R10: 0000000000000004 R11: 0000000000000000 R12: 0000000000000007
R13: 0000607f458ff910 R14: 0000000000000001 R15: 0000607f458ff910
FS: 0000000000000000(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005639ce414030 CR3: 00000000a0e1f000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 66 66 2e 0f 1f 84 00 data16 nopw %cs:0x0(%rax,%rax,1)
7: 00 00 00 00
b: 41 55 push %r13
d: 41 54 push %r12
f: 55 push %rbp
10: 53 push %rbx
11: 48 89 fb mov %rdi,%rbx
14: e8 12 c8 e9 fa callq 0xfae9c82b
19: 48 89 da mov %rbx,%rdx
1c: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
23: fc ff df
26: 48 c1 ea 03 shr $0x3,%rdx
* 2a: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction
2e: 0f 85 e5 01 00 00 jne 0x219
34: 48 8d 7b 3a lea 0x3a(%rbx),%rdi
38: 48 8b 2b mov (%rbx),%rbp
3b: 48 rex.W
3c: b8 .byte 0xb8
3d: 00 00 add %al,(%rax)


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.