bisecting fixing commit since 3d40d7117e353b84627c1e8c5ed9ae0b1237ef5c building syzkaller on ddc3e85997efdad885e208db6a98bca86e5dd52f testing commit 3d40d7117e353b84627c1e8c5ed9ae0b1237ef5c with gcc (GCC) 8.1.0 kernel signature: 92a9b4d0d1ece3665188f2455e599bd8ec716db9b8a1e45acd986aaf8ae83442 all runs: crashed: general protection fault in hsr_check_carrier_and_operstate testing current HEAD 4707d8e5727387e36ea99c74d5ff0ad227700fd0 testing commit 4707d8e5727387e36ea99c74d5ff0ad227700fd0 with gcc (GCC) 8.1.0 kernel signature: 4d964fa569e6c41543cebf17444746e087261d1f12f7f4096eceba29dcec95df all runs: crashed: general protection fault in hsr_check_carrier_and_operstate revisions tested: 2, total time: 25m15.432372953s (build: 17m30.331094174s, test: 6m50.607120054s) the crash still happens on HEAD commit msg: Linux 4.19.126 crash: general protection fault in hsr_check_carrier_and_operstate device bridge21 left promiscuous mode device bridge22 entered promiscuous mode device bridge21 entered promiscuous mode 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: 0 PID: 8700 Comm: syz-executor.2 Not tainted 4.19.126-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:hsr_check_carrier_and_operstate+0x33/0x580 net/hsr/hsr_device.c:116 Code: 41 57 41 56 41 55 41 54 53 48 83 ec 08 e8 75 a6 ff ff 4c 8d 70 10 49 89 c4 48 b8 00 00 00 00 00 fc ff df 4c 89 f2 48 c1 ea 03 <80> 3c 02 00 0f 85 c3 04 00 00 48 b8 00 00 00 00 00 fc ff df 49 8b RSP: 0018:ffff888096a6ec48 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: ffff888095dc0c80 RCX: 1ffff11012bb8184 RDX: 0000000000000002 RSI: 0000000000000004 RDI: ffff888095dc0ca0 RBP: ffff888096a6ec78 R08: fffffbfff11f3195 R09: fffffbfff11f3194 R10: fffffbfff11f3194 R11: ffffffff88f98ca7 R12: 0000000000000000 R13: 0000000000000004 R14: 0000000000000010 R15: ffff8880a0400c40 FS: 00007f63c3a96700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f510672cdb8 CR3: 00000000a952d000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: hsr_netdev_notify+0x36d/0x9f0 net/hsr/hsr_main.c:51 notifier_call_chain+0x8a/0x160 kernel/notifier.c:93 __raw_notifier_call_chain kernel/notifier.c:394 [inline] raw_notifier_call_chain+0x11/0x20 kernel/notifier.c:401 call_netdevice_notifiers_info+0x28/0x60 net/core/dev.c:1748 netdev_state_change+0xd4/0x100 net/core/dev.c:1353 do_setlink+0x1b1a/0x2e10 net/core/rtnetlink.c:2661 rtnl_newlink+0xa18/0x1310 net/core/rtnetlink.c:3077 rtnetlink_rcv_msg+0x34f/0x8f0 net/core/rtnetlink.c:4777 netlink_rcv_skb+0x142/0x390 net/netlink/af_netlink.c:2455 rtnetlink_rcv+0x10/0x20 net/core/rtnetlink.c:4795 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x443/0x650 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x765/0xc40 net/netlink/af_netlink.c:1909 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xb5/0xf0 net/socket.c:632 ___sys_sendmsg+0x647/0x950 net/socket.c:2115 __sys_sendmsg+0xd9/0x180 net/socket.c:2153 __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2160 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45af49 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f63c3a95c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045af49 RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000000000005 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f63c3a966d4 R13: 00000000004ca9a0 R14: 00000000004e3d80 R15: 00000000ffffffff Modules linked in: ---[ end trace 8828128b69a67fcb ]--- RIP: 0010:hsr_check_carrier_and_operstate+0x33/0x580 net/hsr/hsr_device.c:116 Code: 41 57 41 56 41 55 41 54 53 48 83 ec 08 e8 75 a6 ff ff 4c 8d 70 10 49 89 c4 48 b8 00 00 00 00 00 fc ff df 4c 89 f2 48 c1 ea 03 <80> 3c 02 00 0f 85 c3 04 00 00 48 b8 00 00 00 00 00 fc ff df 49 8b RSP: 0018:ffff888096a6ec48 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: ffff888095dc0c80 RCX: 1ffff11012bb8184 RDX: 0000000000000002 RSI: 0000000000000004 RDI: ffff888095dc0ca0 RBP: ffff888096a6ec78 R08: fffffbfff11f3195 R09: fffffbfff11f3194 R10: fffffbfff11f3194 R11: ffffffff88f98ca7 R12: 0000000000000000 R13: 0000000000000004 R14: 0000000000000010 R15: ffff8880a0400c40 FS: 00007f63c3a96700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f510672cdb8 CR3: 00000000a952d000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400