bisecting fixing commit since 32ee7492f104d82b01a44fc4b4ae17d5d2bb237b building syzkaller on 93e5e33559b98e47f3743e6d907ca8444fbba5d4 testing commit 32ee7492f104d82b01a44fc4b4ae17d5d2bb237b with gcc (GCC) 8.1.0 kernel signature: 0b21f05ea863a1526de51d134855820972fa2ff1d8428a61897cab211c00101e all runs: crashed: general protection fault in nft_rhash_insert testing current HEAD 2d16cf4817bc6944a2adb5bf4db607c8258e87da testing commit 2d16cf4817bc6944a2adb5bf4db607c8258e87da with gcc (GCC) 8.1.0 kernel signature: 4b4c3f87d0852275c4f6a7c10e29f0625b9e2cdb5341848f1e8072adab856fca all runs: crashed: general protection fault in nft_rhash_insert revisions tested: 2, total time: 26m5.982637143s (build: 18m28.922632543s, test: 6m16.230285987s) the crash still happens on HEAD commit msg: Linux 4.19.125 crash: general protection fault in nft_rhash_insert batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 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 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! CPU: 1 PID: 7816 Comm: syz-executor.3 Not tainted 4.19.125-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:nft_rhash_insert+0x87/0xe60 net/netfilter/nft_set_hash.c:166 Code: 4c 89 b5 60 ff ff ff c7 01 f1 f1 f1 f1 c7 41 04 00 00 00 f2 65 48 8b 0c 25 28 00 00 00 48 89 4d d0 31 c9 48 89 f9 48 c1 e9 03 <80> 3c 01 00 0f 85 96 0b 00 00 48 8b 42 40 49 8d bd c4 18 00 00 49 RSP: 0018:ffff88808deef038 EFLAGS: 00010203 RAX: dffffc0000000000 RBX: ffff88808deef168 RCX: 03fffffffe248e79 RDX: 1ffffffff124738e RSI: ffff88808deef168 RDI: 1ffffffff12473ce RBP: ffff88808deef120 R08: dffffc0000000000 R09: 0000000000000001 R10: ffffed1011bdde3e R11: ffff88808deef1f7 R12: ffff88808deef0f8 R13: ffff88808deef1c8 R14: 1ffff11011bdde13 R15: ffff88808deef228 FS: 00007feacdd3a700(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa138e91710 CR3: 000000008c920000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: nfnetlink_parse_nat net/netfilter/nf_nat_core.c:847 [inline] nfnetlink_parse_nat_setup+0x1ee/0x340 net/netfilter/nf_nat_core.c:884 ctnetlink_parse_nat_setup+0x7c/0x430 net/netfilter/nf_conntrack_netlink.c:1521 ctnetlink_setup_nat net/netfilter/nf_conntrack_netlink.c:1596 [inline] ctnetlink_create_conntrack+0x3be/0xfa0 net/netfilter/nf_conntrack_netlink.c:1984 ctnetlink_new_conntrack+0x46c/0xe10 net/netfilter/nf_conntrack_netlink.c:2114 nfnetlink_rcv_msg+0x942/0xc05 net/netfilter/nfnetlink.c:228 batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 netlink_rcv_skb+0x142/0x390 net/netlink/af_netlink.c:2455 nfnetlink_rcv+0x163/0x3b0 net/netfilter/nfnetlink.c:560 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 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! __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: 0033:0x45b399 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:00007feacdd39c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007feacdd3a6d4 RCX: 000000000045b399 RDX: 0000000000000000 RSI: 0000000020000640 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000942 R14: 00000000004caa57 R15: 000000000075bf2c Modules linked in: ---[ end trace c0671058ee263c22 ]--- batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 RIP: 0010:nft_rhash_insert+0x87/0xe60 net/netfilter/nft_set_hash.c:166 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! Code: 4c 89 b5 60 ff ff ff c7 01 f1 f1 f1 f1 c7 41 04 00 00 00 f2 65 48 8b 0c 25 28 00 00 00 48 89 4d d0 31 c9 48 89 f9 48 c1 e9 03 <80> 3c 01 00 0f 85 96 0b 00 00 48 8b 42 40 49 8d bd c4 18 00 00 49 RSP: 0018:ffff88808deef038 EFLAGS: 00010203 RAX: dffffc0000000000 RBX: ffff88808deef168 RCX: 03fffffffe248e79 RDX: 1ffffffff124738e RSI: ffff88808deef168 RDI: 1ffffffff12473ce RBP: ffff88808deef120 R08: dffffc0000000000 R09: 0000000000000001 R10: ffffed1011bdde3e R11: ffff88808deef1f7 R12: ffff88808deef0f8 R13: ffff88808deef1c8 R14: 1ffff11011bdde13 R15: ffff88808deef228 FS: 00007feacdd3a700(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa138e91710 CR3: 000000008c920000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400