#!/bin/sh [ `uname -p` != "amd64" ] && exit 0 [ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1 # panic: Assertion lock == sq->sq_lock failed at ../../../kern/subr_sleepqueue.c:371 # cpuid = 1 # time = 1623487895 # KDB: stack backtrace: # db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe06c14b4700 # vpanic() at vpanic+0x181/frame 0xfffffe06c14b4750 # panic() at panic+0x43/frame 0xfffffe06c14b47b0 # sleepq_add() at sleepq_add+0x3e6/frame 0xfffffe06c14b4800 # _sleep() at _sleep+0x20e/frame 0xfffffe06c14b48b0 # kern_sigtimedwait() at kern_sigtimedwait+0x532/frame 0xfffffe06c14b4a20 # sys_sigwaitinfo() at sys_sigwaitinfo+0x43/frame 0xfffffe06c14b4ac0 # amd64_syscall() at amd64_syscall+0x147/frame 0xfffffe06c14b4bf0 # fast_syscall_common() at fast_syscall_common+0xf8/frame 0xfffffe06c14b4bf0 # --- syscall (0, FreeBSD ELF64, nosys), rip = 0x8003af5fa, rsp = 0x7fffffffe5f8, rbp = 0x7fffffffe610 --- # KDB: enter: panic # [ thread pid 15370 tid 356127 ] # Stopped at kdb_enter+0x37: movq $0,0x1285b4e(%rip) # db> x/s version # version: FreeBSD 14.0-CURRENT #0 main-n247326-2349cda44fea: Sat Jun 12 03:57:33 CEST 2021 # pho@mercat1.netperf.freebsd.org:/usr/src/sys/amd64/compile/PHO # db> . ../default.cfg cat > /tmp/syzkaller42.c < #include #include #include #include #include #include #include #include #include #include #include #include #include static void kill_and_wait(int pid, int* status) { kill(pid, SIGKILL); while (waitpid(-1, status, 0) != pid) { } } static void sleep_ms(uint64_t ms) { usleep(ms * 1000); } static uint64_t current_time_ms(void) { struct timespec ts; if (clock_gettime(CLOCK_MONOTONIC, &ts)) exit(1); return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000; } static void execute_one(void); #define WAIT_FLAGS 0 static void loop(void) { int iter __unused = 0; for (;; iter++) { int pid = fork(); if (pid < 0) exit(1); if (pid == 0) { execute_one(); exit(0); } int status = 0; uint64_t start = current_time_ms(); for (;;) { if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) break; sleep_ms(1); if (current_time_ms() - start < 5000) { continue; } kill_and_wait(pid, &status); break; } } } void execute_one(void) { syscall(SYS_rfork, 0x14034ul); *(uint32_t*)0x20000140 = 0x80000002; *(uint32_t*)0x20000144 = 0xfffffff7; *(uint32_t*)0x20000148 = 0x41; *(uint32_t*)0x2000014c = 3; syscall(SYS_sigwaitinfo, 0x20000140ul, 0ul); } int main(void) { syscall(SYS_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x1012ul, -1, 0ul); loop(); return 0; } EOF mycc -o /tmp/syzkaller42 -Wall -Wextra -O0 /tmp/syzkaller42.c -lpthread || exit 1 (cd /tmp; timeout 3m ./syzkaller42) rm -rf /tmp/syzkaller42 /tmp/syzkaller42.c /tmp/syzkaller.* exit 0