#!/bin/sh # panic: Bad tailq NEXT(0xffffffff81cb0ba0->tqh_last) != NULL # cpuid = 0 # time = 1605424954 # KDB: stack backtrace: # db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe010125c2e0 # vpanic() at vpanic+0x182/frame 0xfffffe010125c330 # panic() at panic+0x43/frame 0xfffffe010125c390 # callout_process() at callout_process+0x34f/frame 0xfffffe010125c400 # handleevents() at handleevents+0x185/frame 0xfffffe010125c440 # timercb() at timercb+0x196/frame 0xfffffe010125c490 # lapic_handle_timer() at lapic_handle_timer+0x9b/frame 0xfffffe010125c4c0 # Xtimerint() at Xtimerint+0xb1/frame 0xfffffe010125c4c0 # --- interrupt, rip = 0xffffffff80c56c69, rsp = 0xfffffe010125c590, rbp = 0xfffffe010125c5c0 --- # witness_unlock() at witness_unlock+0x79/frame 0xfffffe010125c5c0 # __mtx_unlock_flags() at __mtx_unlock_flags+0x4d/frame 0xfffffe010125c5f0 # kqueue_register() at kqueue_register+0x9e3/frame 0xfffffe010125c680 # kqueue_kevent() at kqueue_kevent+0x106/frame 0xfffffe010125c950 # kern_kevent_fp() at kern_kevent_fp+0x95/frame 0xfffffe010125c9a0 # kern_kevent() at kern_kevent+0x80/frame 0xfffffe010125ca00 # kern_kevent_generic() at kern_kevent_generic+0x70/frame 0xfffffe010125ca60 # sys_kevent() at sys_kevent+0x61/frame 0xfffffe010125cac0 # amd64_syscall() at amd64_syscall+0x144/frame 0xfffffe010125cbf0 # fast_syscall_common() at fast_syscall_common+0xf8/frame 0xfffffe010125cbf0 # --- syscall (0, FreeBSD ELF64, nosys), rip = 0x800380c6a, rsp = 0x7fffffffe4d8, rbp = 0x7fffffffe500 --- # KDB: enter: panic # [ thread pid 36082 tid 144846 ] # Stopped at kdb_enter+0x37: movq $0,0x10aa7f6(%rip) # db> x/s version # version: FreeBSD 13.0-CURRENT #0 r367672: Sat Nov 14 08:42:14 CET 2020 # pho@t2.osted.lan:/usr/src/sys/amd64/compile/PHO # db> [ `uname -p` != "amd64" ] && exit 0 # Fixed by r367849 . ../default.cfg cat > /tmp/syzkaller27.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 = 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 < 5 * 1000) continue; kill_and_wait(pid, &status); break; } } } uint64_t r[1] = {0xffffffffffffffff}; void execute_one(void) { intptr_t res = 0; res = syscall(SYS_kqueue); if (res != -1) r[0] = res; *(uint64_t*)0x200000c0 = 0; *(uint16_t*)0x200000c8 = 0xfff9; *(uint16_t*)0x200000ca = 0x4001; *(uint32_t*)0x200000cc = 4; *(uint64_t*)0x200000d0 = 0; *(uint64_t*)0x200000d8 = 0; *(uint64_t*)0x200000e0 = 0; *(uint64_t*)0x200000e8 = 0; *(uint64_t*)0x200000f0 = 0; *(uint64_t*)0x200000f8 = 0; syscall(SYS_kevent, r[0], 0x200000c0ul, 1ul, 0ul, 0ul, 0ul); } int main(void) { sleep(2); /* pho */ syscall(SYS_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x1012ul, -1, 0ul); loop(); return 0; } EOF mycc -o /tmp/syzkaller27 -Wall -Wextra -O0 /tmp/syzkaller27.c || exit 1 (cd ../testcases/swap; ./swap -t 1m -i 20 -h > /dev/null 2>&1) & for i in `jot 256`; do (cd /tmp; timeout 3m ./syzkaller27) & done wait rm -rf /tmp/syzkaller27 /tmp/syzkaller27.c /tmp/syzkaller.* exit 0