bisecting fixing commit since 14cfdbd39e316efd91ae6e403ef8211f0b022603 building syzkaller on 68660b21c27c417771037b3f1fe4aa072cfdeef9 testing commit 14cfdbd39e316efd91ae6e403ef8211f0b022603 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 766499c644a1e870bfd81ada7d67fddb7301640ed4731946e866794ea761fa64 run #0: crashed: kernel BUG in sctp_do_sm run #1: crashed: kernel BUG in sctp_do_sm run #2: crashed: kernel BUG in sctp_do_sm run #3: crashed: kernel BUG in sctp_do_sm run #4: crashed: kernel BUG in sctp_do_sm run #5: crashed: kernel BUG in sctp_do_sm run #6: crashed: kernel BUG in sctp_do_sm run #7: crashed: kernel BUG in sctp_do_sm run #8: crashed: kernel BUG in sctp_do_sm run #9: crashed: kernel BUG in sctp_do_sm run #10: crashed: kernel BUG in sctp_do_sm run #11: crashed: kernel BUG in sctp_do_sm run #12: crashed: kernel BUG in sctp_do_sm run #13: crashed: kernel BUG in sctp_do_sm run #14: crashed: kernel BUG in sctp_do_sm run #15: crashed: kernel BUG in sctp_do_sm run #16: crashed: kernel BUG in sctp_do_sm run #17: OK run #18: OK run #19: OK testing current HEAD b172b44fcb1771e083aad806fa96f3f60e2ddfac testing commit b172b44fcb1771e083aad806fa96f3f60e2ddfac compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: b8da69645babe409cbb1e2e145a1f4a527638d6507414b697990674e21566e12 run #0: crashed: kernel BUG in sctp_do_sm run #1: crashed: kernel BUG in sctp_do_sm run #2: crashed: kernel BUG in sctp_do_sm run #3: crashed: kernel BUG in sctp_do_sm run #4: crashed: kernel BUG in sctp_do_sm run #5: crashed: kernel BUG in sctp_do_sm run #6: crashed: kernel BUG in sctp_do_sm run #7: crashed: kernel BUG in sctp_do_sm run #8: OK run #9: OK revisions tested: 2, total time: 37m16.318977569s (build: 18m3.68921807s, test: 18m16.11769872s) the crash still happens on HEAD commit msg: Linux 4.19.206 crash: kernel BUG in sctp_do_sm batman_adv: batadv0: Interface activated: batadv_slave_1 IPv6: ADDRCONF(NETDEV_CHANGE): batadv_slave_1: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_batadv: link becomes ready ------------[ cut here ]------------ kernel BUG at net/sctp/sm_sideeffect.c:1538! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 7227 Comm: syz-executor.5 Not tainted 4.19.206-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1538 [inline] RIP: 0010:sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline] RIP: 0010:sctp_do_sm+0x3a42/0x5040 net/sctp/sm_sideeffect.c:1170 Code: 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 74 08 3c 03 0f 8e d0 12 00 00 f6 83 b0 02 00 00 40 0f 85 7e e5 ff ff e9 a8 e5 ff ff <0f> 0b 49 8d 7d 12 48 89 fa 48 89 f9 48 c1 ea 03 83 e1 07 42 0f b6 RSP: 0018:ffff8881d9cdf958 EFLAGS: 00010246 RAX: ffff8881d9e6a530 RBX: ffff8881d9e6a140 RCX: ffff8881d9e6a770 RDX: 1ffff1103b3cd483 RSI: 0000000000000012 RDI: ffff8881d9e6a418 RBP: ffff8881d9cdfc10 R08: ffff8881d9cdfb38 R09: ffff8881d9425ce8 R10: ffffed103b284d08 R11: ffff8881d9426847 R12: 0000000000000000 R13: ffff8881d9cdfb78 R14: dffffc0000000000 R15: ffff8881d9cdfbe8 FS: 00007f0188e17700(0000) GS:ffff8881f6900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000940004 CR3: 00000001d89c8001 CR4: 00000000001606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: sctp_primitive_SHUTDOWN+0x7c/0xc0 net/sctp/primitive.c:104 sctp_close+0x354/0x750 net/sctp/socket.c:1574 inet_release+0xb4/0x1b0 net/ipv4/af_inet.c:427 inet6_release+0x46/0x60 net/ipv6/af_inet6.c:472 __sock_release+0xc2/0x290 net/socket.c:599 sock_close+0x10/0x20 net/socket.c:1214 __fput+0x249/0x7f0 fs/file_table.c:278 ____fput+0x9/0x10 fs/file_table.c:309 task_work_run+0x108/0x180 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x1a9/0x200 arch/x86/entry/common.c:167 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x413/0x4e0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4641a9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f0188e17198 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: 0000000000000007 RBX: 0000000000000ade RCX: 00000000004641a9 RDX: 000000000000006e RSI: 0000000000000084 RDI: 0000000000000004 RBP: 0000000000000036 R08: 0000000000000020 R09: 0000000000000000 R10: 0000000020000000 R11: 0000000000000246 R12: 000000000053bf00 R13: 00007f0188e176bc R14: 00000000ffffffff R15: 0000000000000005 Modules linked in: ---[ end trace aa0501e2a1f162e1 ]--- RIP: 0010:sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1538 [inline] RIP: 0010:sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline] RIP: 0010:sctp_do_sm+0x3a42/0x5040 net/sctp/sm_sideeffect.c:1170 Code: 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 74 08 3c 03 0f 8e d0 12 00 00 f6 83 b0 02 00 00 40 0f 85 7e e5 ff ff e9 a8 e5 ff ff <0f> 0b 49 8d 7d 12 48 89 fa 48 89 f9 48 c1 ea 03 83 e1 07 42 0f b6 RSP: 0018:ffff8881d9cdf958 EFLAGS: 00010246 RAX: ffff8881d9e6a530 RBX: ffff8881d9e6a140 RCX: ffff8881d9e6a770 RDX: 1ffff1103b3cd483 RSI: 0000000000000012 RDI: ffff8881d9e6a418 RBP: ffff8881d9cdfc10 R08: ffff8881d9cdfb38 R09: ffff8881d9425ce8 R10: ffffed103b284d08 R11: ffff8881d9426847 R12: 0000000000000000 R13: ffff8881d9cdfb78 R14: dffffc0000000000 R15: ffff8881d9cdfbe8 FS: 00007f0188e17700(0000) GS:ffff8881f6900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000053c061 CR3: 00000001d89c8001 CR4: 00000000001606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400