bisecting fixing commit since c14d30dc9987047b439b03d6e6db7d54d9f7f180 building syzkaller on 5ce135324a84d6de67c913f1b725e3fc5ec39535 testing commit c14d30dc9987047b439b03d6e6db7d54d9f7f180 with gcc (GCC) 8.1.0 kernel signature: dfc18c3f4ea8dde4a0dbc1e2fc4e05b035e74efdc4c72f461f6b6c6766f07d2f all runs: crashed: WARNING in rtnl_delete_link testing current HEAD a87f96283793d58b042618c689630db264715274 testing commit a87f96283793d58b042618c689630db264715274 with gcc (GCC) 8.1.0 kernel signature: 239ae9d25cda5e72e9ab5ae26412cba0443a1d94313bc71a9442a99853b1d305 all runs: crashed: WARNING in rtnl_delete_link revisions tested: 2, total time: 23m45.141906786s (build: 16m51.018877064s, test: 6m28.425599033s) the crash still happens on HEAD commit msg: Linux 4.19.145 crash: WARNING in rtnl_delete_link netlink: 12 bytes leftover after parsing attributes in process `syz-executor.4'. device veth0_macvtap left promiscuous mode bond0: Error: Device is in use and cannot be enslaved bond1 (unregistering): Released all slaves ------------[ cut here ]------------ WARNING: CPU: 1 PID: 8995 at net/core/dev.c:8208 rollback_registered_many.cold.62+0xaa/0x329 net/core/dev.c:8208 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 8995 Comm: syz-executor.5 Not tainted 4.19.145-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x17c/0x22a lib/dump_stack.c:118 panic+0x1cd/0x375 kernel/panic.c:186 __warn.cold.7+0x1b/0x3e kernel/panic.c:541 report_bug+0x1a4/0x200 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:178 [inline] do_error_trap+0x200/0x350 arch/x86/kernel/traps.c:296 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:1038 RIP: 0010:rollback_registered_many.cold.62+0xaa/0x329 net/core/dev.c:8208 Code: 00 00 49 89 71 78 e9 b7 54 fe ff 48 c7 c7 20 5a c0 87 e8 1a e1 e4 fb 0f 0b e9 24 5a fe ff 48 c7 c7 20 5a c0 87 e8 07 e1 e4 fb <0f> 0b e9 d9 59 fe ff 4c 89 f8 48 c1 e8 03 80 3c 08 00 75 6c 49 8b RSP: 0018:ffff88808979f260 EFLAGS: 00010286 RAX: 0000000000000024 RBX: ffff888091c0ce00 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff876785e0 RDI: ffffffff8a1a5a60 RBP: ffff88808979f3b0 R08: ffffed1015d65081 R09: ffffed1015d65080 R10: ffffed1015d65080 R11: ffff8880aeb28407 R12: ffff888085ca5bc0 R13: ffff88808979f388 R14: dffffc0000000000 R15: ffffffff878ddc80 unregister_netdevice_many+0x3e/0x1f0 net/core/dev.c:9311 rtnl_delete_link+0xbc/0x110 net/core/rtnetlink.c:2760 rtnl_dellink+0x2d3/0x950 net/core/rtnetlink.c:2814 rtnetlink_rcv_msg+0x34f/0x950 net/core/rtnetlink.c:4778 netlink_rcv_skb+0x13e/0x3d0 net/netlink/af_netlink.c:2455 rtnetlink_rcv+0x10/0x20 net/core/rtnetlink.c:4796 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x443/0x660 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x666/0xc50 net/netlink/af_netlink.c:1909 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xac/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: 0033:0x45d239 Code: 5d b4 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 2b b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fe5d7664c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000002c0c0 RCX: 000000000045d239 RDX: 0000000000000000 RSI: 00000000200002c0 RDI: 0000000000000009 RBP: 000000000118d020 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cfec R13: 00007ffefa78392f R14: 00007fe5d76659c0 R15: 000000000118cfec Kernel Offset: disabled Rebooting in 86400 seconds..