bisecting fixing commit since a03957ab0fd5d7d03b512a72ab9106a1749f556e building syzkaller on 1bfa09b9672821334a7ed926244ebc39910b84f4 testing commit a03957ab0fd5d7d03b512a72ab9106a1749f556e with gcc (GCC) 8.1.0 kernel signature: 81ea029989f6ee051076cbf6d729dd8782026aed90362835dde2376c69860d0f run #0: crashed: general protection fault in flex_array_get run #1: crashed: general protection fault in corrupted run #2: crashed: general protection fault in flex_array_get run #3: crashed: general protection fault in flex_array_get run #4: crashed: general protection fault in flex_array_get run #5: crashed: general protection fault in flex_array_get run #6: crashed: general protection fault in flex_array_get run #7: crashed: general protection fault in flex_array_get run #8: crashed: general protection fault in flex_array_get run #9: crashed: general protection fault in flex_array_get testing current HEAD 765675379b6253b6901563e649a2f87d28ada3ff testing commit 765675379b6253b6901563e649a2f87d28ada3ff with gcc (GCC) 8.1.0 kernel signature: 9989c1c3c7d39be13ad422f86d9ad851a5cbeabd2eb0f13e43a42a2cc20fac0c run #0: crashed: general protection fault in flex_array_get run #1: crashed: general protection fault in flex_array_get run #2: crashed: general protection fault in flex_array_get run #3: crashed: general protection fault in flex_array_get run #4: crashed: general protection fault in corrupted run #5: crashed: general protection fault in flex_array_get run #6: crashed: general protection fault in flex_array_get run #7: crashed: general protection fault in flex_array_get run #8: crashed: general protection fault in flex_array_get run #9: crashed: general protection fault in flex_array_get revisions tested: 2, total time: 27m5.803240991s (build: 18m10.940450217s, test: 7m55.960590643s) the crash still happens on HEAD commit msg: Linux 4.19.119 crash: general protection fault in flex_array_get sctp_make_temp_asoc+0x8b/0x1a0 net/sctp/sm_make_chunk.c:1602 kasan: GPF could be caused by NULL-ptr deref or user memory access sctp_sf_do_unexpected_init.isra.37+0x66c/0x1400 net/sctp/sm_statefuns.c:1554 sctp_sf_do_5_2_1_siminit+0xf/0x20 net/sctp/sm_statefuns.c:1695 sctp_do_sm+0x117/0x53b0 net/sctp/sm_sideeffect.c:1167 general protection fault: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 7493 Comm: syz-executor.5 Not tainted 4.19.119-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:flex_array_get+0x23/0x240 lib/flex_array.c:320 Code: 90 90 90 90 90 90 90 48 b8 00 00 00 00 00 fc ff df 55 48 89 fa 48 89 e5 48 c1 ea 03 41 56 41 55 41 54 53 48 89 fb 48 83 ec 10 <0f> b6 04 02 84 c0 74 08 3c 03 0f 8e 8d 01 00 00 44 8b 33 45 85 f6 RSP: 0018:ffff88808c6d75a0 EFLAGS: 00010286 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 1ffff11010bfe256 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff88808c6d75d0 R08: 0000000000000000 R09: ffffed1015d64732 R10: ffffed1015d64732 R11: ffff8880aeb23993 R12: ffff888093c24dc0 R13: ffff888071202d04 R14: ffff88808a36cc00 R15: 1ffff11012784aa1 FS: 00007efea8e69700(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000056188c666920 CR3: 0000000097c00000 CR4: 00000000001406e0 sctp_assoc_bh_rcv+0x27f/0x5c0 net/sctp/associola.c:1073 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 sctp_inq_push+0x1aa/0x240 net/sctp/inqueue.c:95 Call Trace: sctp_backlog_rcv+0x1ac/0x1280 net/sctp/input.c:356 sctp_stream_out include/net/sctp/structs.h:1474 [inline] sctp_sched_dequeue_done+0x1d8/0x300 net/sctp/stream_sched.c:255 __sctp_outq_teardown+0x660/0xc30 net/sctp/outqueue.c:267 sctp_outq_free+0x9/0x10 net/sctp/outqueue.c:291 sctp_association_free+0x1d5/0x711 net/sctp/associola.c:361 sctp_cmd_delete_tcb net/sctp/sm_sideeffect.c:944 [inline] sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1332 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline] sctp_do_sm+0x9a2/0x53b0 net/sctp/sm_sideeffect.c:1170 sk_backlog_rcv include/net/sock.h:946 [inline] __release_sock+0x10c/0x360 net/core/sock.c:2342 release_sock+0x4f/0x180 net/core/sock.c:2858 sctp_wait_for_connect+0x22c/0x4c0 net/sctp/socket.c:8632 sctp_sendmsg_to_asoc+0x10e8/0x15d0 net/sctp/socket.c:1986 sctp_primitive_SHUTDOWN+0x7c/0xc0 net/sctp/primitive.c:104 sctp_sendmsg+0xd4f/0x17e0 net/sctp/socket.c:2132 sctp_close+0x354/0x750 net/sctp/socket.c:1560 inet_release+0xb9/0x1b0 net/ipv4/af_inet.c:427 __sock_release+0xc7/0x2a0 net/socket.c:579 inet_sendmsg+0x10d/0x450 net/ipv4/af_inet.c:798 sock_close+0x10/0x20 net/socket.c:1140 __fput+0x24c/0x7f0 fs/file_table.c:278 ____fput+0x9/0x10 fs/file_table.c:309 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xb7/0xf0 net/socket.c:632 task_work_run+0x10e/0x190 kernel/task_work.c:113 ___sys_sendmsg+0x649/0x950 net/socket.c:2115 get_signal+0x139f/0x1a00 kernel/signal.c:2399 do_signal+0x87/0x1960 arch/x86/kernel/signal.c:821 __sys_sendmsg+0xd9/0x180 net/socket.c:2153 exit_to_usermode_loop+0x114/0x200 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x419/0x4e0 arch/x86/entry/common.c:296 __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 entry_SYSCALL_64_after_hwframe+0x49/0xbe do_syscall_64+0xd6/0x4e0 arch/x86/entry/common.c:293 RIP: 0033:0x458da9 entry_SYSCALL_64_after_hwframe+0x49/0xbe Code: ad b8 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 b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RIP: 0033:0x458da9 RSP: 002b:00007efea8e68c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e Code: ad b8 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 b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RAX: 000000000001fff8 RBX: 00007efea8e68c90 RCX: 0000000000458da9 RSP: 002b:00007f138526bc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000003 RAX: ffffffffffffffda RBX: 00007f138526bc90 RCX: 0000000000458da9 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000003 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007efea8e696d4 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f138526c6d4 R13: 00000000004c5ff5 R14: 00000000004da7d8 R15: 0000000000000005 R13: 00000000004c5ff5 R14: 00000000004da7d8 R15: 0000000000000005 FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 Modules linked in: CPU: 1 PID: 7505 Comm: syz-executor.2 Tainted: G D 4.19.119-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 fail_dump lib/fault-inject.c:51 [inline] should_fail.cold.4+0x5/0x13 lib/fault-inject.c:149 __should_failslab+0xba/0xf0 mm/failslab.c:32 should_failslab+0x9/0x14 mm/slab_common.c:1558 slab_pre_alloc_hook mm/slab.h:424 [inline] slab_alloc mm/slab.c:3383 [inline] kmem_cache_alloc+0x47/0x730 mm/slab.c:3557 kmem_cache_zalloc include/linux/slab.h:699 [inline] fill_pool lib/debugobjects.c:134 [inline] __debug_object_init+0x7dc/0xd70 lib/debugobjects.c:379 debug_object_init+0x16/0x20 lib/debugobjects.c:431 debug_timer_init kernel/time/timer.c:704 [inline] debug_init kernel/time/timer.c:757 [inline] init_timer_key+0x2e/0x270 kernel/time/timer.c:806 sctp_association_init net/sctp/associola.c:153 [inline] sctp_association_new+0x9fd/0x1ef0 net/sctp/associola.c:317 sctp_make_temp_asoc+0x8b/0x1a0 net/sctp/sm_make_chunk.c:1602 sctp_sf_do_unexpected_init.isra.37+0x66c/0x1400 net/sctp/sm_statefuns.c:1554 sctp_sf_do_5_2_1_siminit+0xf/0x20 net/sctp/sm_statefuns.c:1695 sctp_do_sm+0x117/0x53b0 net/sctp/sm_sideeffect.c:1167 sctp_assoc_bh_rcv+0x27f/0x5c0 net/sctp/associola.c:1073 sctp_inq_push+0x1aa/0x240 net/sctp/inqueue.c:95 sctp_backlog_rcv+0x1ac/0x1280 net/sctp/input.c:356 sk_backlog_rcv include/net/sock.h:946 [inline] __release_sock+0x10c/0x360 net/core/sock.c:2342 release_sock+0x4f/0x180 net/core/sock.c:2858 sctp_wait_for_connect+0x22c/0x4c0 net/sctp/socket.c:8632 sctp_sendmsg_to_asoc+0x10e8/0x15d0 net/sctp/socket.c:1986 sctp_sendmsg+0xd4f/0x17e0 net/sctp/socket.c:2132 inet_sendmsg+0x10d/0x450 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xb7/0xf0 net/socket.c:632 ___sys_sendmsg+0x649/0x950 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+0xd6/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458da9 Code: ad b8 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 b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fdc4635ac78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fdc4635ac90 RCX: 0000000000458da9 RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000003 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fdc4635b6d4 R13: 00000000004c5ff5 R14: 00000000004da7d8 R15: 0000000000000005 CPU: 0 PID: 7513 Comm: syz-executor.1 Tainted: G D 4.19.119-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ---[ end trace f5025c0d4304fa8a ]--- Call Trace: RIP: 0010:flex_array_get+0x23/0x240 lib/flex_array.c:320 __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x123/0x177 lib/dump_stack.c:118 Code: 90 90 90 90 90 90 90 48 b8 00 00 00 00 00 fc ff df 55 48 89 fa 48 89 e5 48 c1 ea 03 41 56 41 55 41 54 53 48 89 fb 48 83 ec 10 <0f> b6 04 02 84 c0 74 08 3c 03 0f 8e 8d 01 00 00 44 8b 33 45 85 f6 fail_dump lib/fault-inject.c:51 [inline] should_fail.cold.4+0x5/0x13 lib/fault-inject.c:149 __should_failslab+0xba/0xf0 mm/failslab.c:32 should_failslab+0x9/0x14 mm/slab_common.c:1558 slab_pre_alloc_hook mm/slab.h:424 [inline] slab_alloc_node mm/slab.c:3304 [inline] kmem_cache_alloc_node+0x56/0x730 mm/slab.c:3647 RSP: 0018:ffff88808c6d75a0 EFLAGS: 00010286 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 1ffff11010bfe256 __alloc_skb+0xa7/0x580 net/core/skbuff.c:193 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 alloc_skb include/linux/skbuff.h:995 [inline] sctp_packet_transmit+0x26b/0x3490 net/sctp/output.c:584 RBP: ffff88808c6d75d0 R08: 0000000000000000 R09: ffffed1015d64732 R10: ffffed1015d64732 R11: ffff8880aeb23993 R12: ffff888093c24dc0 sctp_outq_flush_transports net/sctp/outqueue.c:1165 [inline] sctp_outq_flush+0x252/0x22f0 net/sctp/outqueue.c:1213 R13: ffff888071202d04 R14: ffff88808a36cc00 R15: 1ffff11012784aa1 sctp_outq_uncork+0x49/0x60 net/sctp/outqueue.c:776 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1807 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline] sctp_do_sm+0x107d/0x53b0 net/sctp/sm_sideeffect.c:1170 FS: 00007efea8e69700(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe90d1e1000 CR3: 0000000097c00000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 sctp_assoc_bh_rcv+0x27f/0x5c0 net/sctp/associola.c:1073 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 sctp_inq_push+0x1aa/0x240 net/sctp/inqueue.c:95 sctp_backlog_rcv+0x1ac/0x1280 net/sctp/input.c:356