bisecting cause commit starting from 6c677750f22db3bb466a95f08b91a1cca8323146 building syzkaller on 88bc17df053022a7c2a3753b299b06a9eff19c1a testing commit 6c677750f22db3bb466a95f08b91a1cca8323146 with gcc (GCC) 8.1.0 kernel signature: 7930db4d9dc7933020212b54735170c66d946209 all runs: crashed: WARNING in xfrm_policy_insert testing release v4.15 testing commit d8a5b80568a9cb66810e75b182018e9edb68e8ff with gcc (GCC) 8.1.0 kernel signature: 167d04bc42e7f11fd91e439f24b758500d6bcdb3 all runs: crashed: WARNING in xfrm_policy_insert testing release v4.14 testing commit bebc6082da0a9f5d47a1ea2edc099bf671058bd4 with gcc (GCC) 8.1.0 kernel signature: d003910f2e9d04d2d89de67affb211c3975044b1 all runs: crashed: WARNING in xfrm_policy_insert testing release v4.13 testing commit 569dbb88e80deb68974ef6fdd6a13edb9d686261 with gcc (GCC) 8.1.0 kernel signature: 90d8a3f40b284cad2635db1616f5e4e51274c37a all runs: crashed: WARNING in xfrm_policy_insert testing release v4.12 testing commit 6f7da290413ba713f0cdd9ff1a2a9bb129ef4f6c with gcc (GCC) 8.1.0 kernel signature: 1dce788cb9c6ef07062b13d938b6c826d0b34916 all runs: crashed: WARNING in xfrm_policy_insert testing release v4.11 testing commit a351e9b9fc24e982ec2f0e76379a49826036da12 with gcc (GCC) 7.3.0 kernel signature: ed37373d0c38240155de1dc006eb94f685af4806 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 corrupted run #4: crashed: WARNING in xfrm_policy_insert run #5: crashed: WARNING in xfrm_policy_insert run #6: crashed: general protection fault in flow_cache_flush run #7: crashed: general protection fault in flow_cache_flush run #8: crashed: general protection fault in flow_cache_flush run #9: crashed: general protection fault in flow_cache_flush testing release v4.10 testing commit c470abd4fde40ea6a0846a2beab642a578c0b8cd with gcc (GCC) 5.5.0 kernel signature: d717856fc3cda930e183235d1b87f0281d8c8c59 all runs: crashed: WARNING in xfrm_policy_insert testing release v4.9 testing commit 69973b830859bc6529a7a0468ba0d80ee5117826 with gcc (GCC) 5.5.0 kernel signature: 0483fd03fac12ea0e48291f55cbf081c39488d1c 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 release v4.8 testing commit c8d2bc9bc39ebea8437fd974fdbc21847bb897a3 with gcc (GCC) 5.5.0 kernel signature: 3c36a99d2aaa0d6007a3ee543c5e69064ae19aed 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 xfrm_policy_insert run #7: crashed: WARNING in xfrm_policy_insert run #8: crashed: WARNING in xfrm_policy_insert run #9: crashed: WARNING in corrupted testing release v4.7 testing commit 523d939ef98fd712632d93a5a2b588e477a7565e with gcc (GCC) 5.5.0 kernel signature: 05113b975ed2858b305b99c9af590e9577916420 all runs: crashed: WARNING in xfrm_policy_insert testing release v4.6 testing commit 2dcd0af568b0cf583645c8a317dd12e344b1c72a with gcc (GCC) 5.5.0 kernel signature: 6ad5ac32711b73f6cc2e5ab68fcc7743b9702956 all runs: crashed: WARNING in xfrm_policy_insert testing release v4.5 testing commit b562e44f507e863c6792946e4e1b1449fbbac85d with gcc (GCC) 5.5.0 kernel signature: 72a8d943f7560470262b864c6f439791a501d712 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 testing release v4.4 testing commit afd2ff9b7e1b367172f18ba7f693dfb62bdcb2dc with gcc (GCC) 5.5.0 kernel signature: 5db93719d9241086901703354941ec21d9990f46 run #0: crashed: WARNING in corrupted 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 xfrm_policy_insert run #7: crashed: WARNING in xfrm_policy_insert run #8: crashed: WARNING in xfrm_policy_insert run #9: OK testing release v4.3 testing commit 6a13feb9c82803e2b815eca72fa7a9f5561d7861 with gcc (GCC) 5.5.0 kernel signature: f14980ded8ac801c9700ea3f2fe346436503c49d all runs: crashed: WARNING in xfrm_policy_insert testing release v4.2 testing commit 64291f7db5bd8150a74ad2036f1037e6a0428df2 with gcc (GCC) 5.5.0 kernel signature: ba3faf928d9bb0b470b345f536a68da488506e57 all runs: crashed: WARNING in xfrm_policy_insert testing release v4.1 testing commit b953c0d234bc72e8489d3bf51a276c5c4ec85345 with gcc (GCC) 5.5.0 kernel signature: 3d7e042334267fb41c317c173a458688f8c57e1a all runs: crashed: WARNING in xfrm_policy_insert revisions tested: 16, total time: 3h9m54.505468057s (build: 45m34.566345248s, test: 2h19m41.008855081s) the crash already happened on the oldest tested release commit msg: Linux 4.1 crash: WARNING in xfrm_policy_insert ------------[ cut here ]------------ WARNING: CPU: 0 PID: 30399 at net/xfrm/xfrm_policy.c:764 xfrm_policy_insert+0x38b/0x3e0 net/xfrm/xfrm_policy.c:764() Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 30399 Comm: syz-executor Not tainted 4.1.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ffffffff824dda50 ffff880215aff928 ffffffff81fb9ae4 0000000000000032 ffffffff824200ae ffff880215aff9a8 ffffffff81fb7a81 ffff880215aff948 ffffffff00000008 ffff880215aff9b8 ffff880215aff958 0000000000000000 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0x4c/0x65 lib/dump_stack.c:50 [] panic+0xcd/0x211 kernel/panic.c:111 [] warn_slowpath_common+0xbb/0xc0 kernel/panic.c:442 [] warn_slowpath_null+0x15/0x20 kernel/panic.c:479 [] xfrm_policy_insert+0x38b/0x3e0 net/xfrm/xfrm_policy.c:764 [] xfrm_add_policy+0xa8/0x140 net/xfrm/xfrm_user.c:1504 [] xfrm_user_rcv_msg+0x109/0x1d0 net/xfrm/xfrm_user.c:2466 [] netlink_rcv_skb+0xa9/0xd0 net/netlink/af_netlink.c:2843 [] xfrm_netlink_rcv+0x32/0x40 net/xfrm/xfrm_user.c:2474 [] netlink_unicast_kernel net/netlink/af_netlink.c:1763 [inline] [] netlink_unicast+0x1ce/0x2f0 net/netlink/af_netlink.c:1789 [] netlink_sendmsg+0x310/0x3d0 net/netlink/af_netlink.c:2353 [] sock_sendmsg_nosec net/socket.c:613 [inline] [] sock_sendmsg+0x35/0x40 net/socket.c:623 [] ___sys_sendmsg+0x2d3/0x2e0 net/socket.c:1955 [] __sys_sendmsg+0x3d/0x80 net/socket.c:1989 [] SYSC_sendmsg net/socket.c:2000 [inline] [] SyS_sendmsg+0xd/0x20 net/socket.c:1996 [] system_call_fastpath+0x16/0x7a Kernel Offset: disabled