From: YueHaibing <yuehaibing@xxxxxxxxxx> [ Upstream commit 36096f2f4fa05f7678bc87397665491700bae757 ] kernel BUG at lib/list_debug.c:47! invalid opcode: 0000 [#1 CPU: 0 PID: 12914 Comm: rmmod Tainted: G W 5.1.0+ #47 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014 RIP: 0010:__list_del_entry_valid+0x53/0x90 Code: 48 8b 32 48 39 fe 75 35 48 8b 50 08 48 39 f2 75 40 b8 01 00 00 00 5d c3 48 89 fe 48 89 c2 48 c7 c7 18 75 fe 82 e8 cb 34 78 ff <0f> 0b 48 89 fe 48 c7 c7 50 75 fe 82 e8 ba 34 78 ff 0f 0b 48 89 f2 RSP: 0018:ffffc90001c2fe40 EFLAGS: 00010286 RAX: 000000000000004e RBX: ffffffffa0184000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff888237a17788 RDI: 00000000ffffffff RBP: ffffc90001c2fe40 R08: 0000000000000000 R09: 0000000000000000 R10: ffffc90001c2fe10 R11: 0000000000000000 R12: 0000000000000000 R13: ffffc90001c2fe50 R14: ffffffffa0184000 R15: 0000000000000000 FS: 00007f3d83634540(0000) GS:ffff888237a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555c350ea818 CR3: 0000000231677000 CR4: 00000000000006f0 Call Trace: unregister_pernet_operations+0x34/0x120 unregister_pernet_subsys+0x1c/0x30 packet_exit+0x1c/0x369 [af_packet __x64_sys_delete_module+0x156/0x260 ? lockdep_hardirqs_on+0x133/0x1b0 ? do_syscall_64+0x12/0x1f0 do_syscall_64+0x6e/0x1f0 entry_SYSCALL_64_after_hwframe+0x49/0xbe When modprobe af_packet, register_pernet_subsys fails and does a cleanup, ops->list is set to LIST_POISON1, but the module init is considered to success, then while rmmod it, BUG() is triggered in __list_del_entry_valid which is called from unregister_pernet_subsys. This patch fix error handing path in packet_init to avoid possilbe issue if some error occur. Reported-by: Hulk Robot <hulkci@xxxxxxxxxx> Signed-off-by: YueHaibing <yuehaibing@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/packet/af_packet.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-) --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -4604,14 +4604,29 @@ static void __exit packet_exit(void) static int __init packet_init(void) { - int rc = proto_register(&packet_proto, 0); + int rc; - if (rc != 0) + rc = proto_register(&packet_proto, 0); + if (rc) goto out; + rc = sock_register(&packet_family_ops); + if (rc) + goto out_proto; + rc = register_pernet_subsys(&packet_net_ops); + if (rc) + goto out_sock; + rc = register_netdevice_notifier(&packet_netdev_notifier); + if (rc) + goto out_pernet; - sock_register(&packet_family_ops); - register_pernet_subsys(&packet_net_ops); - register_netdevice_notifier(&packet_netdev_notifier); + return 0; + +out_pernet: + unregister_pernet_subsys(&packet_net_ops); +out_sock: + sock_unregister(PF_PACKET); +out_proto: + proto_unregister(&packet_proto); out: return rc; }