bisecting fixing commit since 7250956f6eafc6edf2ad9a1cccaffb7f16c7b38d building syzkaller on 8fe30d3e866b08b8be5adcefa561b901175dca28 testing commit 7250956f6eafc6edf2ad9a1cccaffb7f16c7b38d with gcc (GCC) 8.1.0 kernel signature: 57f8ee6d80c05f425f97adfbcff50787444bfc50100dc09ea7dc97e19e2573d0 run #0: crashed: general protection fault in prepare_to_wait run #1: crashed: general protection fault in prepare_to_wait run #2: crashed: KASAN: use-after-free Read in lock_sock_nested run #3: OK run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK testing current HEAD 399849e4654ea496a6217ba4e5ee3d304c995ab4 testing commit 399849e4654ea496a6217ba4e5ee3d304c995ab4 with gcc (GCC) 8.1.0 kernel signature: 1acfd1a077acd08a9f132251584bbb18cf4ba2287fa415c7928a5e26506bb7b8 run #0: crashed: general protection fault in prepare_to_wait run #1: crashed: general protection fault in prepare_to_wait run #2: OK run #3: OK run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK revisions tested: 2, total time: 36m12.58603543s (build: 16m15.235101856s, test: 19m26.512623715s) the crash still happens on HEAD commit msg: Linux 4.19.131 crash: general protection fault in prepare_to_wait audit: type=1400 audit(1593762544.464:11): avc: denied { write } for pid=7278 comm="syz-executor.4" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:unlabeled_t:s0 tclass=socket permissive=1 IPv6: ADDRCONF(NETDEV_UP): vxcan1: link is not ready 8021q: adding VLAN 0 to HW filter on device batadv0 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 CPU: 0 PID: 7284 Comm: syz-executor.1 Not tainted 4.19.131-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__lock_acquire+0x1e0/0x4980 kernel/locking/lockdep.c:3294 Code: 28 00 00 00 0f 85 2a 30 00 00 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 28 32 00 00 49 81 7d 00 60 d1 0b 89 0f 84 4a ff RSP: 0018:ffff88808f75f900 EFLAGS: 00010006 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000003 RSI: 0000000000000000 RDI: ffffffff88120b00 RBP: ffff88808f75faf0 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000018 R14: ffff888095216240 R15: 0000000000000000 FS: 00007fe0f70fc700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5c61a85db8 CR3: 0000000096e4f000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x173/0x3d0 kernel/locking/lockdep.c:3907 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x99/0xd0 kernel/locking/spinlock.c:152 prepare_to_wait+0x90/0x310 kernel/sched/wait.c:230 nr_accept+0x1b0/0x640 net/netrom/af_netrom.c:796 __sys_accept4+0x32b/0x6b0 net/socket.c:1589 __do_sys_accept net/socket.c:1630 [inline] __se_sys_accept net/socket.c:1627 [inline] __x64_sys_accept+0x70/0xb0 net/socket.c:1627 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459829 Code: fd b7 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 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fe0f70fbc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002b RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459829 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe0f70fc6d4 R13: 00000000004bf6e9 R14: 00000000004d0f80 R15: 00000000ffffffff Modules linked in: ---[ end trace 311a6ceef45c811a ]--- RIP: 0010:__lock_acquire+0x1e0/0x4980 kernel/locking/lockdep.c:3294 Code: 28 00 00 00 0f 85 2a 30 00 00 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 28 32 00 00 49 81 7d 00 60 d1 0b 89 0f 84 4a ff RSP: 0018:ffff88808f75f900 EFLAGS: 00010006 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000003 RSI: 0000000000000000 RDI: ffffffff88120b00 RBP: ffff88808f75faf0 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000018 R14: ffff888095216240 R15: 0000000000000000 FS: 00007fe0f70fc700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5c61a85db8 CR3: 0000000096e4f000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400