panic: runtime error: invalid memory address or nil pointer dereference [signal SIGSEGV: segmentation violation code=0x1 addr=0x28 pc=0x5a6c84] goroutine 1 [running]: main.diffProgInfo(0x0, 0x1eaf4?) /syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/fuzzer.go:432 +0x24 main.(*FuzzerTool).diffMaxSignal(0x38?, 0x6d9fa0?) /syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/fuzzer.go:442 +0xb8 main.(*FuzzerTool).convertExecutionResult(0x64c720?, {{0x71ad, {0x400109e000, 0x129be, 0x129be}, 0x0, 0x0, 0x0, 0x1, 0x0}, ...}) /syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/fuzzer.go:386 +0x74 main.(*FuzzerTool).exchangeDataCall(0x400045a000, 0x1, {0x400108ba58, 0x1, 0x691f00?}) /syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/fuzzer.go:345 +0x314 main.(*FuzzerTool).exchangeDataWorker(0x400045a000) /syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/fuzzer.go:380 +0x58 main.main() /syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/fuzzer.go:273 +0x1100 D0325 21:16:09.690337 263709 task_signals.go:204] [ 2054: 2054] Signal 9, PID: 2054, TID: 2054, fault addr: 0x0: terminating thread group D0325 21:16:09.690361 263709 task_exit.go:204] [ 2054: 2054] Transitioning from exit state TaskExitNone to TaskExitInitiated D0325 21:16:09.690372 263709 task_signals.go:204] [ 3289: 3289] Signal 9, PID: 3289, TID: 3289, fault addr: 0x0: terminating thread group D0325 21:16:09.690382 263709 task_exit.go:204] [ 3289: 3289] Transitioning from exit state TaskExitNone to TaskExitInitiated D0325 21:16:09.690440 263709 task_signals.go:470] [ 2057( 1): 2057( 1)] Notified of signal 9 D0325 21:16:09.690450 263709 task_exit.go:204] [ 2054: 2054] Transitioning from exit state TaskExitInitiated to TaskExitZombie D0325 21:16:09.690457 263709 task_signals.go:481] [ 6: 6] No task notified of signal 17 D0325 21:16:09.690470 263709 task_signals.go:204] [ 4789: 4789] Signal 9, PID: 4789, TID: 4789, fault addr: 0x0: terminating thread group D0325 21:16:09.690476 263709 task_exit.go:204] [ 4789: 4789] Transitioning from exit state TaskExitNone to TaskExitInitiated D0325 21:16:09.690562 263709 task_signals.go:470] [ 4792( 1): 4792( 1)] Notified of signal 9 D0325 21:16:09.690571 263709 task_exit.go:204] [ 4789: 4789] Transitioning from exit state TaskExitInitiated to TaskExitZombie D0325 21:16:09.690575 263709 task_signals.go:458] [ 6: 6] Discarding duplicate signal 17 D0325 21:16:09.690589 263709 task_signals.go:470] [ 3043( 1): 3043( 1)] Notified of signal 9 D0325 21:16:09.690597 263709 task_exit.go:204] [ 3041: 3041] Transitioning from exit state TaskExitInitiated to TaskExitZombie D0325 21:16:09.690601 263709 task_signals.go:458] [ 6: 6] Discarding duplicate signal 17 D0325 21:16:09.690778 263709 task_signals.go:204] [ 4792( 1): 4792( 1)] Signal 9, PID: 4792, TID: 4792, fault addr: 0x0: terminating thread group D0325 21:16:09.690822 263709 task_exit.go:204] [ 4792( 1): 4792( 1)] Transitioning from exit state TaskExitNone to TaskExitInitiated D0325 21:16:09.690883 263709 task_signals.go:204] [ 2057( 1): 2057( 1)] Signal 9, PID: 2057, TID: 2057, fault addr: 0x0: terminating thread group D0325 21:16:09.690913 263709 task_exit.go:361] [ 4792( 1): 4792( 1)] Init process terminating, killing namespace D0325 21:16:09.690927 263709 task_signals.go:470] [ 5601( 239): 5601( 239)] Notified of signal 9 D0325 21:16:09.690935 263709 task_signals.go:458] [ 5601( 239): 5601( 239)] Discarding duplicate signal 9 D0325 21:16:09.690940 263709 task_exit.go:204] [ 4792( 1): 4792( 1)] Transitioning from exit state TaskExitInitiated to TaskExitZombie D0325 21:16:09.690954 263709 task_signals.go:470] [ 1: 1] Notified of signal 17 D0325 21:16:09.690988 263709 task_exit.go:204] [ 2057( 1): 2057( 1)] Transitioning from exit state TaskExitNone to TaskExitInitiated D0325 21:16:09.691042 263709 task_signals.go:204] [ 5601( 239): 5601( 239)] Signal 9, PID: 5601, TID: 5601, fault addr: 0x0: terminating thread group D0325 21:16:09.691046 263709 task_signals.go:179] [ 1: 1] Restarting syscall 98: interrupted by signal 17 D0325 21:16:09.691058 263709 task_signals.go:220] [ 1: 1] Signal 17: delivering to handler D0325 21:16:09.691186 263709 task_signals.go:204] [ 5601( 239): 5603( 240)] Signal 9, PID: 5601, TID: 5603, fault addr: 0x0: terminating thread group D0325 21:16:09.691225 263709 task_signals.go:204] [ 3043( 1): 3043( 1)] Signal 9, PID: 3043, TID: 3043, fault addr: 0x0: terminating thread group D0325 21:16:09.691232 263709 task_exit.go:361] [ 2057( 1): 2057( 1)] Init process terminating, killing namespace D0325 21:16:09.691260 263709 task_signals.go:476] [ 5617( 846): 5620( 847)] Notified of group signal 9 D0325 21:16:09.691287 263709 task_stop.go:138] [ 3768( 386): 3768( 386)] Leaving internal stop (*kernel.groupStop)(nil) D0325 21:16:09.691300 263709 task_signals.go:481] [ 3768( 386): 3768( 386)] No task notified of signal 9 D0325 21:16:09.691308 263709 task_signals.go:458] [ 5617( 846): 5617( 846)] Discarding duplicate signal 9 D0325 21:16:09.691323 263709 task_exit.go:204] [ 2057( 1): 2057( 1)] Transitioning from exit state TaskExitInitiated to TaskExitZombie D0325 21:16:09.691331 263709 task_signals.go:470] [ 1: 1] Notified of signal 17 D0325 21:16:09.691347 263709 task_signals.go:204] [ 5617( 846): 5625( 848)] Signal 9, PID: 5617, TID: 5625, fault addr: 0x0: terminating thread group D0325 21:16:09.691371 263709 task_signals.go:204] [ 3768( 386): 3768( 386)] Signal 9, PID: 3768, TID: 3768, fault addr: 0x0: terminating thread group D0325 21:16:09.691381 263709 task_exit.go:204] [ 5617( 846): 5625( 848)] Transitioning from exit state TaskExitNone to TaskExitInitiated D0325 21:16:09.691396 263709 task_signals.go:204] [ 5601( 239): 5608( 241)] Signal 9, PID: 5601, TID: 5608, fault addr: 0x0: terminating thread group D0325 21:16:09.691404 263709 task_signals.go:179] [ 1: 1] Restarting syscall 98: interrupted by signal 17 D0325 21:16:09.691409 263709 task_signals.go:220] [ 1: 1] Signal 17: delivering to handler D0325 21:16:09.691537 263709 task_signals.go:204] [ 5617( 846): 5620( 847)] Signal 9, PID: 5617, TID: 5620, fault addr: 0x0: terminating thread group D0325 21:16:09.691558 263709 task_exit.go:204] [ 5617( 846): 5625( 848)] Transitioning from exit state TaskExitInitiated to TaskExitZombie D0325 21:16:09.691563 263709 task_exit.go:204] [ 5617( 846): 5625( 848)] Transitioning from exit state TaskExitZombie to TaskExitDead D0325 21:16:09.691583 263709 task_signals.go:470] [ 3290( 1): 3290( 1)] Notified of signal 9 D0325 21:16:09.691590 263709 task_exit.go:204] [ 3289: 3289] Transitioning from exit state TaskExitInitiated to TaskExitZombie D0325 21:16:09.691595 263709 task_signals.go:458] [ 6: 6] Discarding duplicate signal 17 D0325 21:16:09.691604 263709 task_exit.go:204] [ 3768( 386): 3768( 386)] Transitioning from exit state TaskExitNone to TaskExitInitiated D0325 21:16:09.691654 263709 task_exit.go:361] [ 3768( 386): 3768( 386)] Init process terminating, killing namespace D0325 21:16:09.691750 263709 task_signals.go:458] [ 5617( 846): 5617( 846)] Discarding duplicate signal 9 D0325 21:16:09.691756 263709 task_signals.go:458] [ 2057( 1): 2057( 1)] Discarding duplicate signal 9 D0325 21:16:09.691771 263709 task_exit.go:204] [ 3768( 386): 3768( 386)] Transitioning from exit state TaskExitInitiated to TaskExitZombie D0325 21:16:09.691775 263709 task_exit.go:204] [ 3768( 386): 3768( 386)] Transitioning from exit state TaskExitZombie to TaskExitDead D0325 21:16:09.691795 263709 task_exit.go:204] [ 5601( 239): 5601( 239)] Transitioning from exit state TaskExitNone to TaskExitInitiated D0325 21:16:09.691807 263709 task_exit.go:204] [ 5601( 239): 5601( 239)] Transitioning from exit state TaskExitInitiated to TaskExitZombie D0325 21:16:09.691821 263709 task_signals.go:204] [ 3290( 1): 3290( 1)] Signal 9, PID: 3290, TID: 3290, fault addr: 0x0: terminating thread group D0325 21:16:09.691828 263709 task_exit.go:204] [ 3290( 1): 3290( 1)] Transitioning from exit state TaskExitNone to TaskExitInitiated D0325 21:16:09.691866 263709 task_exit.go:361] [ 3290( 1): 3290( 1)] Init process terminating, killing namespace D0325 21:16:09.691872 263709 task_stop.go:138] [ 4519( 307): 4519( 307)] Leaving internal stop (*kernel.groupStop)(nil) D0325 21:16:09.691879 263709 task_signals.go:481] [ 4519( 307): 4519( 307)] No task notified of signal 9 D0325 21:16:09.691885 263709 task_exit.go:204] [ 3290( 1): 3290( 1)] Transitioning from exit state TaskExitInitiated to TaskExitZombie D0325 21:16:09.691890 263709 task_signals.go:470] [ 1: 1] Notified of signal 17 D0325 21:16:09.691899 263709 task_exit.go:204] [ 5601( 239): 5603( 240)] Transitioning from exit state TaskExitNone to TaskExitInitiated D0325 21:16:09.691914 263709 task_exit.go:204] [ 5601( 239): 5603( 240)] Transitioning from exit state TaskExitInitiated to TaskExitZombie D0325 21:16:09.691920 263709 task_exit.go:204] [ 5601( 239): 5603( 240)] Transitioning from exit state TaskExitZombie to TaskExitDead D0325 21:16:09.692422 263709 task_exit.go:204] [ 3043( 1): 3043( 1)] Transitioning from exit state TaskExitNone to TaskExitInitiated D0325 21:16:09.692499 263709 task_exit.go:361] [ 3043( 1): 3043( 1)] Init process terminating, killing namespace D0325 21:16:09.692507 263709 task_stop.go:138] [ 3524( 135): 3524( 135)] Leaving internal stop (*kernel.groupStop)(nil) D0325 21:16:09.692516 263709 task_signals.go:481] [ 3524( 135): 3524( 135)] No task notified of signal 9 D0325 21:16:09.692522 263709 task_stop.go:138] [ 4372( 338): 4372( 338)] Leaving internal stop (*kernel.groupStop)(nil) D0325 21:16:09.692528 263709 task_signals.go:481] [ 4372( 338): 4372( 338)] No task notified of signal 9 D0325 21:16:09.692533 263709 task_stop.go:138] [ 4436( 375): 4436( 375)] Leaving internal stop (*kernel.groupStop)(nil) D0325 21:16:09.692538 263709 task_signals.go:481] [ 4436( 375): 4436( 375)] No task notified of signal 9 D0325 21:16:09.692543 263709 task_exit.go:204] [ 3043( 1): 3043( 1)] Transitioning from exit state TaskExitInitiated to TaskExitZombie D0325 21:16:09.692549 263709 task_signals.go:458] [ 1: 1] Discarding duplicate signal 17 D0325 21:16:09.692719 263709 task_signals.go:204] [ 4519( 307): 4519( 307)] Signal 9, PID: 4519, TID: 4519, fault addr: 0x0: terminating thread group D0325 21:16:09.692733 263709 task_exit.go:204] [ 4519( 307): 4519( 307)] Transitioning from exit state TaskExitNone to TaskExitInitiated D0325 21:16:09.692759 263709 task_signals.go:179] [ 1: 1] Restarting syscall 98: interrupted by signal 17 D0325 21:16:09.692775 263709 task_signals.go:220] [ 1: 1] Signal 17: delivering to handler D0325 21:16:09.692856 263709 task_exit.go:204] [ 5601( 239): 5608( 241)] Transitioning from exit state TaskExitNone to TaskExitInitiated D0325 21:16:09.693029 263709 task_exit.go:361] [ 4519( 307): 4519( 307)] Init process terminating, killing namespace D0325 21:16:09.693048 263709 task_signals.go:458] [ 3290( 1): 3290( 1)] Discarding duplicate signal 9 D0325 21:16:09.693055 263709 task_exit.go:204] [ 4519( 307): 4519( 307)] Transitioning from exit state TaskExitInitiated to TaskExitZombie D0325 21:16:09.693060 263709 task_exit.go:204] [ 4519( 307): 4519( 307)] Transitioning from exit state TaskExitZombie to TaskExitDead D0325 21:16:09.693079 263709 task_signals.go:204] [ 3524( 135): 3524( 135)] Signal 9, PID: 3524, TID: 3524, fault addr: 0x0: terminating thread group D0325 21:16:09.693087 263709 task_exit.go:204] [ 3524( 135): 3524( 135)] Transitioning from exit state TaskExitNone to TaskExitInitiated D0325 21:16:09.693106 263709 task_exit.go:361] [ 5601( 239): 5608( 241)] Init process terminating, killing namespace D0325 21:16:09.693121 263709 task_signals.go:458] [ 4792( 1): 4792( 1)] Discarding duplicate signal 9 D0325 21:16:09.693141 263709 task_exit.go:204] [ 5601( 239): 5608( 241)] Transitioning from exit state TaskExitInitiated to TaskExitZombie D0325 21:16:09.693147 263709 task_exit.go:204] [ 5601( 239): 5608( 241)] Transitioning from exit state TaskExitZombie to TaskExitDead D0325 21:16:09.693153 263709 task_exit.go:204] [ 5601( 239): 5601( 239)] Transitioning from exit state TaskExitZombie to TaskExitDead D0325 21:16:09.693167 263709 task_exit.go:204] [ 5617( 846): 5620( 847)] Transitioning from exit state TaskExitNone to TaskExitInitiated D0325 21:16:09.693180 263709 task_exit.go:204] [ 5617( 846): 5620( 847)] Transitioning from exit state TaskExitInitiated to TaskExitZombie D0325 21:16:09.693189 263709 task_exit.go:204] [ 5617( 846): 5620( 847)] Transitioning from exit state TaskExitZombie to TaskExitDead D0325 21:16:09.694323 263709 task_signals.go:204] [ 4372( 338): 4372( 338)] Signal 9, PID: 4372, TID: 4372, fault addr: 0x0: terminating thread group D0325 21:16:09.694382 263709 task_exit.go:204] [ 4372( 338): 4372( 338)] Transitioning from exit state TaskExitNone to TaskExitInitiated D0325 21:16:09.694466 263709 task_exit.go:361] [ 4372( 338): 4372( 338)] Init process terminating, killing namespace D0325 21:16:09.694477 263709 task_signals.go:458] [ 3043( 1): 3043( 1)] Discarding duplicate signal 9 D0325 21:16:09.694487 263709 task_signals.go:458] [ 3524( 135): 3524( 135)] Discarding duplicate signal 9 D0325 21:16:09.694493 263709 task_signals.go:458] [ 4436( 375): 4436( 375)] Discarding duplicate signal 9 D0325 21:16:09.694547 263709 task_exit.go:204] [ 4372( 338): 4372( 338)] Transitioning from exit state TaskExitInitiated to TaskExitZombie D0325 21:16:09.694568 263709 task_exit.go:204] [ 4372( 338): 4372( 338)] Transitioning from exit state TaskExitZombie to TaskExitDead D0325 21:16:09.694690 263709 task_signals.go:204] [ 4436( 375): 4436( 375)] Signal 9, PID: 4436, TID: 4436, fault addr: 0x0: terminating thread group D0325 21:16:09.694725 263709 task_exit.go:204] [ 4436( 375): 4436( 375)] Transitioning from exit state TaskExitNone to TaskExitInitiated D0325 21:16:09.694826 263709 task_exit.go:361] [ 3524( 135): 3524( 135)] Init process terminating, killing namespace D0325 21:16:09.694856 263709 task_signals.go:458] [ 3043( 1): 3043( 1)] Discarding duplicate signal 9 D0325 21:16:09.694868 263709 task_signals.go:458] [ 4436( 375): 4436( 375)] Discarding duplicate signal 9 D0325 21:16:09.694877 263709 task_exit.go:204] [ 3524( 135): 3524( 135)] Transitioning from exit state TaskExitInitiated to TaskExitZombie D0325 21:16:09.694887 263709 task_exit.go:204] [ 3524( 135): 3524( 135)] Transitioning from exit state TaskExitZombie to TaskExitDead D0325 21:16:09.695271 263709 task_exit.go:361] [ 4436( 375): 4436( 375)] Init process terminating, killing namespace D0325 21:16:09.695292 263709 task_signals.go:458] [ 3043( 1): 3043( 1)] Discarding duplicate signal 9 D0325 21:16:09.695303 263709 task_exit.go:204] [ 4436( 375): 4436( 375)] Transitioning from exit state TaskExitInitiated to TaskExitZombie D0325 21:16:09.695309 263709 task_exit.go:204] [ 4436( 375): 4436( 375)] Transitioning from exit state TaskExitZombie to TaskExitDead D0325 21:16:09.697069 263709 task_signals.go:204] [ 5617( 846): 5617( 846)] Signal 9, PID: 5617, TID: 5617, fault addr: 0x0: terminating thread group D0325 21:16:09.697097 263709 task_exit.go:204] [ 5617( 846): 5617( 846)] Transitioning from exit state TaskExitNone to TaskExitInitiated D0325 21:16:09.703444 263828 urpc.go:611] urpc: unmarshal success. I0325 21:16:09.703500 263828 main.go:226] Exiting with status: 512 D0325 21:16:09.702602 263709 task_signals.go:458] [ 3041: 3041] Discarding duplicate signal 9 D0325 21:16:09.702640 263709 task_signals.go:470] [ 1: 1] Notified of signal 17 D0325 21:16:09.702653 263709 task_signals.go:458] [ 3289: 3289] Discarding duplicate signal 9 D0325 21:16:09.702658 263709 task_signals.go:458] [ 1: 1] Discarding duplicate signal 17 D0325 21:16:09.702665 263709 task_signals.go:458] [ 4789: 4789] Discarding duplicate signal 9 D0325 21:16:09.702669 263709 task_signals.go:458] [ 1: 1] Discarding duplicate signal 17 D0325 21:16:09.702675 263709 task_signals.go:458] [ 2054: 2054] Discarding duplicate signal 9 D0325 21:16:09.702679 263709 task_signals.go:458] [ 1: 1] Discarding duplicate signal 17 D0325 21:16:09.702684 263709 task_exit.go:204] [ 6: 18447] Transitioning from exit state TaskExitInitiated to TaskExitZombie D0325 21:16:09.702691 263709 task_exit.go:204] [ 6: 18447] Transitioning from exit state TaskExitZombie to TaskExitDead D0325 21:16:09.702697 263709 task_exit.go:204] [ 6: 6] Transitioning from exit state TaskExitZombie to TaskExitDead D0325 21:16:09.702766 263709 task_signals.go:179] [ 1: 1] Restarting syscall 98: interrupted by signal 17 D0325 21:16:09.702775 263709 task_signals.go:220] [ 1: 1] Signal 17: delivering to handler D0325 21:16:09.703127 263709 task_exit.go:361] [ 5617( 846): 5617( 846)] Init process terminating, killing namespace D0325 21:16:09.703153 263709 task_signals.go:458] [ 2057( 1): 2057( 1)] Discarding duplicate signal 9 D0325 21:16:09.703160 263709 task_exit.go:204] [ 5617( 846): 5617( 846)] Transitioning from exit state TaskExitInitiated to TaskExitZombie D0325 21:16:09.703167 263709 task_exit.go:204] [ 5617( 846): 5617( 846)] Transitioning from exit state TaskExitZombie to TaskExitDead D0325 21:16:09.703271 263709 loader.go:1259] updated processes (removal): map[{ci-gvisor-arm64-ptrace-1-1 0}:0x4000295c20] D0325 21:16:09.703296 263709 controller.go:523] containerManager.Wait, cid: ci-gvisor-arm64-ptrace-1-1, pid: 6, waitStatus: 0x200, err: D0325 21:16:09.703346 263709 urpc.go:568] urpc: successfully marshalled 38 bytes. D0325 21:16:09.790339 263709 urpc.go:611] urpc: unmarshal success. D0325 21:16:09.839376 263709 urpc.go:568] urpc: successfully marshalled 279645 bytes. D0325 21:16:09.863165 263709 urpc.go:611] urpc: unmarshal success. D0325 21:16:09.863228 263709 controller.go:232] containerManager.Processes, cid: ci-gvisor-arm64-ptrace-1-1 D0325 21:16:09.863516 263709 urpc.go:568] urpc: successfully marshalled 5353 bytes. D0325 21:16:09.883536 263709 sampler.go:191] Time: Adjusting syscall overhead down to 7 D0325 21:16:10.883849 263709 sampler.go:191] Time: Adjusting syscall overhead down to 7 D0325 21:16:11.883830 263709 sampler.go:191] Time: Adjusting syscall overhead down to 7 D0325 21:16:11.883891 263709 sampler.go:191] Time: Adjusting syscall overhead down to 7 D0325 21:16:12.883737 263709 sampler.go:191] Time: Adjusting syscall overhead down to 7 D0325 21:16:13.883762 263709 sampler.go:191] Time: Adjusting syscall overhead down to 7 D0325 21:16:14.883311 263709 sampler.go:191] Time: Adjusting syscall overhead down to 7 D0325 21:16:15.883787 263709 sampler.go:191] Time: Adjusting syscall overhead down to 7 D0325 21:16:16.883952 263709 sampler.go:191] Time: Adjusting syscall overhead down to 7 D0325 21:16:17.883053 263709 sampler.go:191] Time: Adjusting syscall overhead down to 7 D0325 21:16:18.883460 263709 sampler.go:191] Time: Adjusting syscall overhead down to 7 D0325 21:16:19.883068 263709 sampler.go:191] Time: Adjusting syscall overhead down to 7