bisecting fixing commit since dd81e1c7d5fb126e5fbc5c9e334d7b3ec29a16a0 building syzkaller on 214351e168def9426c79e1f65a93ddb112cee906 testing commit dd81e1c7d5fb126e5fbc5c9e334d7b3ec29a16a0 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: a35a357c173c674dbaa174fa85fe3e1d49f69b5993067daa34d51c8fcae9e4d6 run #0: basic kernel testing failed: BUG: program execution failed: executor NUM: EOF run #1: crashed: BUG: "hc->tx_t_ipi == NUM" holds (exception!) at net/dccp/ccids/ccid3.c:LINE/ccid3_update_send_interval() run #2: crashed: BUG: "hc->tx_t_ipi == NUM" holds (exception!) at net/dccp/ccids/ccid3.c:LINE/ccid3_update_send_interval() run #3: crashed: BUG: "hc->tx_t_ipi == NUM" holds (exception!) at net/dccp/ccids/ccid3.c:LINE/ccid3_update_send_interval() run #4: crashed: BUG: "hc->tx_t_ipi == NUM" holds (exception!) at net/dccp/ccids/ccid3.c:LINE/ccid3_update_send_interval() run #5: crashed: BUG: "hc->tx_t_ipi == NUM" holds (exception!) at net/dccp/ccids/ccid3.c:LINE/ccid3_update_send_interval() run #6: crashed: BUG: "hc->tx_t_ipi == NUM" holds (exception!) at net/dccp/ccids/ccid3.c:LINE/ccid3_update_send_interval() run #7: crashed: BUG: "hc->tx_t_ipi == NUM" holds (exception!) at net/dccp/ccids/ccid3.c:LINE/ccid3_update_send_interval() run #8: crashed: BUG: please report to dccp@vger.kernel.org => prev = NUM, last = NUM at net/dccp/ccids/lib/packet_history.c:LINE/tfrc_rx run #9: crashed: BUG: "hc->tx_t_ipi == NUM" holds (exception!) at net/dccp/ccids/ccid3.c:LINE/ccid3_update_send_interval() run #10: OK run #11: OK run #12: crashed: BUG: "hc->tx_t_ipi == NUM" holds (exception!) at net/dccp/ccids/ccid3.c:LINE/ccid3_update_send_interval() run #13: OK run #14: OK run #15: OK run #16: OK run #17: OK run #18: OK run #19: OK testing current HEAD ed4643521e6af8ab8ed1e467630a85884d2696cf testing commit ed4643521e6af8ab8ed1e467630a85884d2696cf compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 51663dc65ce526b7e3cd8c0627e75c1e55f89bad3ddfc50fd4efb37cbf536b84 all runs: crashed: BUG: "hc->tx_t_ipi == NUM" holds (exception!) at net/dccp/ccids/ccid3.c:LINE/ccid3_update_send_interval() revisions tested: 2, total time: 21m18.635467214s (build: 12m14.320857842s, test: 8m27.256027791s) the crash still happens on HEAD commit msg: Merge tag 'arm-dt-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc crash: BUG: "hc->tx_t_ipi == NUM" holds (exception!) at net/dccp/ccids/ccid3.c:LINE/ccid3_update_send_interval() BUG: "hc->tx_t_ipi == 0" holds (exception!) at net/dccp/ccids/ccid3.c:90/ccid3_update_send_interval() CPU: 0 PID: 4162 Comm: syz-executor180 Tainted: G W 5.17.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x57/0x7d lib/dump_stack.c:106 ccid3_hc_tx_update_s net/dccp/ccids/ccid3.c:169 [inline] ccid3_hc_tx_packet_sent+0xda/0x110 net/dccp/ccids/ccid3.c:353 ccid_hc_tx_packet_sent net/dccp/ccid.h:175 [inline] dccp_xmit_packet+0x28a/0x660 net/dccp/output.c:289 dccp_write_xmit+0x10e/0x180 net/dccp/output.c:366 dccp_sendmsg+0x6ef/0xa80 net/dccp/proto.c:783 sock_sendmsg_nosec net/socket.c:705 [inline] sock_sendmsg+0xab/0xe0 net/socket.c:725 ____sys_sendmsg+0x392/0x7a0 net/socket.c:2413 ___sys_sendmsg+0xd3/0x150 net/socket.c:2467 __sys_sendmmsg+0x141/0x310 net/socket.c:2553 __do_sys_sendmmsg net/socket.c:2582 [inline] __se_sys_sendmmsg net/socket.c:2579 [inline] __x64_sys_sendmmsg+0x94/0x100 net/socket.c:2579 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f4cf06d6e29 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 18 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f4cf067d2f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 0000000000000039 RCX: 00007f4cf06d6e29 RDX: 0000000000000001 RSI: 0000000020000fc0 RDI: 0000000000000004 RBP: 00007f4cf07584a8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4cf07584a0 R13: 00007f4cf07584ac R14: 00007f4cf07256dc R15: e7594119f9b8c840 BUG: "hc->tx_t_ipi == 0" holds (exception!) at net/dccp/ccids/ccid3.c:90/ccid3_update_send_interval() CPU: 0 PID: 4162 Comm: syz-executor180 Tainted: G W 5.17.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x57/0x7d lib/dump_stack.c:106 ccid3_hc_tx_update_s net/dccp/ccids/ccid3.c:169 [inline] ccid3_hc_tx_packet_sent+0xda/0x110 net/dccp/ccids/ccid3.c:353 ccid_hc_tx_packet_sent net/dccp/ccid.h:175 [inline] dccp_xmit_packet+0x28a/0x660 net/dccp/output.c:289 dccp_write_xmit+0x10e/0x180 net/dccp/output.c:366 dccp_sendmsg+0x6ef/0xa80 net/dccp/proto.c:783 sock_sendmsg_nosec net/socket.c:705 [inline] sock_sendmsg+0xab/0xe0 net/socket.c:725 ____sys_sendmsg+0x392/0x7a0 net/socket.c:2413 ___sys_sendmsg+0xd3/0x150 net/socket.c:2467 __sys_sendmmsg+0x141/0x310 net/socket.c:2553 __do_sys_sendmmsg net/socket.c:2582 [inline] __se_sys_sendmmsg net/socket.c:2579 [inline] __x64_sys_sendmmsg+0x94/0x100 net/socket.c:2579 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f4cf06d6e29 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 18 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f4cf067d2f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 0000000000000037 RCX: 00007f4cf06d6e29 RDX: 0000000000000001 RSI: 0000000020000fc0 RDI: 0000000000000004 RBP: 00007f4cf07584a8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4cf07584a0 R13: 00007f4cf07584ac R14: 00007f4cf07256dc R15: e7594119f9b8c840