general protection fault, probably for non-canonical address 0xdffffc0000000182: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000c10-0x0000000000000c17] CPU: 0 PID: 10667 Comm: kworker/0:21 Not tainted 5.15.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events iterate_cleanup_work RIP: 0010:__ref_is_percpu include/linux/percpu-refcount.h:174 [inline] RIP: 0010:percpu_ref_put_many include/linux/percpu-refcount.h:319 [inline] RIP: 0010:percpu_ref_put include/linux/percpu-refcount.h:338 [inline] RIP: 0010:cgroup_bpf_put include/linux/cgroup.h:926 [inline] RIP: 0010:cgroup_sk_free+0x8d/0x570 kernel/cgroup/cgroup.c:6613 Code: 0e 06 00 40 84 ed 5a 0f 84 42 01 00 00 e8 0b 08 06 00 4c 8d ab 10 0c 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 6f 04 00 00 48 8b ab 10 0c 00 00 31 ff 49 89 ec RSP: 0018:ffffc90000007c58 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000100 RDX: 0000000000000182 RSI: ffffffff81700385 RDI: 0000000000000003 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff81700376 R11: 0000000000000000 R12: ffff88823bddc000 R13: 0000000000000c10 R14: ffffffff8d0d0c4c R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055eab9d406a0 CR3: 000000007b138000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: sk_prot_free net/core/sock.c:1852 [inline] __sk_destruct+0x579/0x900 net/core/sock.c:1943 sk_destruct+0xbd/0xe0 net/core/sock.c:1958 __sk_free+0xef/0x3d0 net/core/sock.c:1969 sk_free+0x78/0xa0 net/core/sock.c:1980 sock_put include/net/sock.h:1804 [inline] nr_heartbeat_expiry+0x2e7/0x460 net/netrom/nr_timer.c:148 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x675/0xa20 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 do_softirq.part.0+0xde/0x130 kernel/softirq.c:459 do_softirq kernel/softirq.c:451 [inline] __local_bh_enable_ip+0x102/0x120 kernel/softirq.c:383 local_bh_enable include/linux/bottom_half.h:32 [inline] get_next_corpse net/netfilter/nf_conntrack_core.c:2252 [inline] nf_ct_iterate_cleanup+0x15a/0x450 net/netfilter/nf_conntrack_core.c:2275 nf_ct_iterate_cleanup_net net/netfilter/nf_conntrack_core.c:2363 [inline] nf_ct_iterate_cleanup_net+0x236/0x400 net/netfilter/nf_conntrack_core.c:2347 iterate_cleanup_work+0x45/0x130 net/netfilter/nf_nat_masquerade.c:216 process_one_work+0x9bf/0x16b0 kernel/workqueue.c:2297 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Modules linked in: ---[ end trace e8f4f8b9240db810 ]--- RIP: 0010:__ref_is_percpu include/linux/percpu-refcount.h:174 [inline] RIP: 0010:percpu_ref_put_many include/linux/percpu-refcount.h:319 [inline] RIP: 0010:percpu_ref_put include/linux/percpu-refcount.h:338 [inline] RIP: 0010:cgroup_bpf_put include/linux/cgroup.h:926 [inline] RIP: 0010:cgroup_sk_free+0x8d/0x570 kernel/cgroup/cgroup.c:6613 Code: 0e 06 00 40 84 ed 5a 0f 84 42 01 00 00 e8 0b 08 06 00 4c 8d ab 10 0c 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 6f 04 00 00 48 8b ab 10 0c 00 00 31 ff 49 89 ec RSP: 0018:ffffc90000007c58 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000100 RDX: 0000000000000182 RSI: ffffffff81700385 RDI: 0000000000000003 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff81700376 R11: 0000000000000000 R12: ffff88823bddc000 R13: 0000000000000c10 R14: ffffffff8d0d0c4c R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055eab9d406a0 CR3: 000000007b138000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 00 40 84 add %al,-0x7c(%rax) 3: ed in (%dx),%eax 4: 5a pop %rdx 5: 0f 84 42 01 00 00 je 0x14d b: e8 0b 08 06 00 callq 0x6081b 10: 4c 8d ab 10 0c 00 00 lea 0xc10(%rbx),%r13 17: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 1e: fc ff df 21: 4c 89 ea mov %r13,%rdx 24: 48 c1 ea 03 shr $0x3,%rdx * 28: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction 2c: 0f 85 6f 04 00 00 jne 0x4a1 32: 48 8b ab 10 0c 00 00 mov 0xc10(%rbx),%rbp 39: 31 ff xor %edi,%edi 3b: 49 89 ec mov %rbp,%r12