bisecting fixing commit since 672481c2deffb371d8a7dfdc009e44c09864a869
building syzkaller on bc5869180f69e2ad6c6b823e129e08a8e523d800
testing commit 672481c2deffb371d8a7dfdc009e44c09864a869 with gcc (GCC) 8.1.0
kernel signature: 2952b498ed109d94a1fdee604a01c8519611c1f3
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: crashed: WARNING in corrupted
run #7: crashed: WARNING in xfrm_policy_insert
run #8: crashed: WARNING in xfrm_policy_insert
run #9: crashed: WARNING in xfrm_policy_insert
testing current HEAD dc4ba5be1babd3b3ec905751a30df89a5899a7a9
testing commit dc4ba5be1babd3b3ec905751a30df89a5899a7a9 with gcc (GCC) 8.1.0
kernel signature: 543fa20bf7516e3bd8c0cfe70280db697ea5311c
run #0: crashed: WARNING in xfrm_policy_insert
run #1: crashed: WARNING in corrupted
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: crashed: WARNING in xfrm_policy_insert
run #7: crashed: WARNING in xfrm_policy_insert
run #8: crashed: WARNING in xfrm_policy_insert
run #9: crashed: WARNING in xfrm_policy_insert
revisions tested: 2, total time: 26m48.913355494s (build: 19m6.46159745s, test: 6m34.664726941s)
the crash still happens on HEAD
commit msg: Linux 4.19.97
crash: WARNING in xfrm_policy_insert
IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): vxcan0: link becomes ready
8021q: adding VLAN 0 to HW filter on device batadv0
------------[ cut here ]------------
WARNING: CPU: 0 PID: 8296 at net/xfrm/xfrm_policy.c:761 xfrm_policy_insert.cold.57+0x18/0xb4 net/xfrm/xfrm_policy.c:761
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 8296 Comm: syz-executor.5 Not tainted 4.19.97-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:1037
RIP: 0010:xfrm_policy_insert.cold.57+0x18/0xb4 net/xfrm/xfrm_policy.c:761
Code: 8b 75 d0 eb a9 48 89 df e8 10 5b b3 fb 8b 75 d0 eb de 48 c7 c7 e0 94 c8 87 4c 89 45 88 48 89 4d 90 4c 89 4d 98 e8 42 f5 6f 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:ffff88808b017478 EFLAGS: 00010286
RAX: 0000000000000024 RBX: ffff888090188040 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8766ec20 RDI: ffffffff8a18ab20
RBP: ffff88808b017510 R08: ffffed1015d45079 R09: ffffed1015d45078
R10: ffffed1015d45078 R11: ffff8880aea283c7 R12: dffffc0000000000
R13: ffff88809f53b200 R14: ffff88809f53b2b4 R15: ffff8880a795a4c0
 xfrm_add_policy+0x220/0x530 net/xfrm/xfrm_user.c:1669
 xfrm_user_rcv_msg+0x34c/0x710 net/xfrm/xfrm_user.c:2677
 netlink_rcv_skb+0x142/0x390 net/netlink/af_netlink.c:2454
 xfrm_netlink_rcv+0x69/0x90 net/xfrm/xfrm_user.c:2685
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x443/0x650 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x765/0xc40 net/netlink/af_netlink.c:1908
 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: 0033:0x45a919
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:00007f779086ec78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a919
RDX: 0000000000000000 RSI: 000000002014f000 RDI: 0000000000000004
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f779086f6d4
R13: 00000000004c9a46 R14: 00000000004e1928 R15: 00000000ffffffff
Kernel Offset: disabled
Rebooting in 86400 seconds..