bisecting fixing commit since 9b15f7fae677336e04b9e026ff91854e43165455
building syzkaller on 5d7b90f1af2e3bf33992b75e7fcf0bab6bf49bd6
testing commit 9b15f7fae677336e04b9e026ff91854e43165455 with gcc (GCC) 8.1.0
kernel signature: f1cab7a16eaf3d9fc890ac25c81a6bace36027a1a47a0e977b52182fec24f1e6
run #0: crashed: WARNING in xfrm_policy_insert
run #1: crashed: WARNING in xfrm_policy_insert
run #2: crashed: WARNING in xfrm_policy_insert
run #3: crashed: WARNING in xfrm_policy_insert
run #4: crashed: WARNING in xfrm_policy_insert
run #5: crashed: WARNING in xfrm_policy_insert
run #6: OK
run #7: OK
run #8: OK
run #9: OK
testing current HEAD 1bab61d3e8cd96f2badf515dcb06e4e1029bc017
testing commit 1bab61d3e8cd96f2badf515dcb06e4e1029bc017 with gcc (GCC) 8.1.0
kernel signature: bc9d1bbf0bbfdcf7d5f95a3674ccc4ba2b8697dbc6aa714d73203076364eec2a
run #0: crashed: WARNING in xfrm_policy_insert
run #1: crashed: WARNING in xfrm_policy_insert
run #2: crashed: WARNING in xfrm_policy_insert
run #3: crashed: WARNING in xfrm_policy_insert
run #4: OK
run #5: OK
run #6: OK
run #7: OK
run #8: OK
run #9: OK
revisions tested: 2, total time: 40m42.759319196s (build: 18m26.261061213s, test: 21m53.595496691s)
the crash still happens on HEAD
commit msg: Linux 4.19.124
crash: WARNING in xfrm_policy_insert
netlink: 11579 bytes leftover after parsing attributes in process `syz-executor.1'.
netlink: 11579 bytes leftover after parsing attributes in process `syz-executor.0'.
netlink: 11579 bytes leftover after parsing attributes in process `syz-executor.2'.
------------[ cut here ]------------
WARNING: CPU: 1 PID: 15240 at net/xfrm/xfrm_policy.c:763 xfrm_policy_insert.cold.56+0x18/0xb4 net/xfrm/xfrm_policy.c:763
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 15240 Comm: syz-executor.0 Not tainted 4.19.124-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+0x123/0x177 lib/dump_stack.c:118
 panic+0x1cd/0x375 kernel/panic.c:186
 __warn.cold.8+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:xfrm_policy_insert.cold.56+0x18/0xb4 net/xfrm/xfrm_policy.c:763
Code: c7 c7 a0 d6 c8 87 48 89 e5 e8 bf 8a 68 fb 0f 0b 5d c3 48 c7 c7 a0 d6 c8 87 4c 89 45 88 48 89 4d 90 4c 89 4d 98 e8 a3 8a 68 fb <0f> 0b 4c 8b 45 88 4c 89 f0 83 e0 07 4c 8b 4d 98 83 c0 03 48 8b 4d
RSP: 0018:ffff8880a008f5c0 EFLAGS: 00010282
RAX: 0000000000000024 RBX: ffff8880a8f1d6c0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff876780c0 RDI: ffffffff8a187960
RBP: ffff8880a008f658 R08: ffffed1015d65079 R09: ffffed1015d65078
R10: ffffed1015d65078 R11: ffff8880aeb283c7 R12: dffffc0000000000
R13: ffff888089bffb00 R14: ffff888089bffbb4 R15: ffff888089ed2dc0
 xfrm_add_policy+0x26c/0x5b0 net/xfrm/xfrm_user.c:1670
 xfrm_user_rcv_msg+0x34c/0x710 net/xfrm/xfrm_user.c:2681
 netlink_rcv_skb+0x142/0x390 net/netlink/af_netlink.c:2455
 xfrm_netlink_rcv+0x69/0x90 net/xfrm/xfrm_user.c:2689
 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_sendto+0x1f2/0x2e0 net/socket.c:1787
 __do_sys_sendto net/socket.c:1799 [inline]
 __se_sys_sendto net/socket.c:1795 [inline]
 __x64_sys_sendto+0xdc/0x1a0 net/socket.c:1795
 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c6c9
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:00007f964791ac78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f964791b6d4 RCX: 000000000045c6c9
RDX: 000000000000ff3b RSI: 0000000020000000 RDI: 0000000000000005
RBP: 000000000076bf20 R08: 0000000000000000 R09: fffffffffffffd62
R10: 0f00000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000009d6 R14: 00000000004cc793 R15: 000000000076bf2c
Kernel Offset: disabled
Rebooting in 86400 seconds..