// https://syzkaller.appspot.com/bug?id=551caecda79d01e87848b52289840fdff31fe255 // autogenerated by syzkaller (https://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include 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 bool write_file(const char* file, const char* what, ...) { char buf[1024]; va_list args; va_start(args, what); vsnprintf(buf, sizeof(buf), what, args); va_end(args); buf[sizeof(buf) - 1] = 0; int len = strlen(buf); int fd = open(file, O_WRONLY | O_CLOEXEC); if (fd == -1) return false; if (write(fd, buf, len) != len) { int err = errno; close(fd); errno = err; return false; } close(fd); return true; } static long syz_open_dev(volatile long a0, volatile long a1, volatile long a2) { if (a0 == 0xc || a0 == 0xb) { char buf[128]; sprintf(buf, "/dev/%s/%d:%d", a0 == 0xc ? "char" : "block", (uint8_t)a1, (uint8_t)a2); return open(buf, O_RDWR, 0); } else { unsigned long nb = a1; char buf[1024]; char* hash; strncpy(buf, (char*)a0, sizeof(buf) - 1); buf[sizeof(buf) - 1] = 0; while ((hash = strchr(buf, '#'))) { *hash = '0' + (char)(nb % 10); nb /= 10; } return open(buf, a2 & ~O_CREAT, 0); } } static void kill_and_wait(int pid, int* status) { kill(-pid, SIGKILL); kill(pid, SIGKILL); for (int i = 0; i < 100; i++) { if (waitpid(-1, status, WNOHANG | __WALL) == pid) return; usleep(1000); } DIR* dir = opendir("/sys/fs/fuse/connections"); if (dir) { for (;;) { struct dirent* ent = readdir(dir); if (!ent) break; if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0) continue; char abort[300]; snprintf(abort, sizeof(abort), "/sys/fs/fuse/connections/%s/abort", ent->d_name); int fd = open(abort, O_WRONLY); if (fd == -1) { continue; } if (write(fd, abort, 1) < 0) { } close(fd); } closedir(dir); } else { } while (waitpid(-1, status, __WALL) != pid) { } } static void setup_test() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); write_file("/proc/self/oom_score_adj", "1000"); } static void execute_one(void); #define WAIT_FLAGS __WALL static void loop(void) { int iter = 0; for (;; iter++) { int pid = fork(); if (pid < 0) exit(1); if (pid == 0) { setup_test(); execute_one(); exit(0); } int status = 0; uint64_t start = current_time_ms(); for (;;) { sleep_ms(10); if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) break; if (current_time_ms() - start < 5000) continue; kill_and_wait(pid, &status); break; } } } uint64_t r[1] = {0xffffffffffffffff}; void execute_one(void) { intptr_t res = 0; if (write(1, "executing program\n", sizeof("executing program\n") - 1)) { } // syz_open_dev$dvb_demux arguments: [ // dev: ptr[in, buffer] { // buffer: {2f 64 65 76 2f 64 76 62 2f 61 64 61 70 74 65 72 23 2f 64 65 // 6d 75 78 23 00} (length 0x19) // } // id: intptr = 0x0 (8 bytes) // flags: open_flags = 0x700 (8 bytes) // ] // returns fd_dvb_demux memcpy((void*)0x200000000400, "/dev/dvb/adapter#/demux#\000", 25); res = -1; res = syz_open_dev(/*dev=*/0x200000000400, /*id=*/0, /*flags=O_TRUNC|O_NOCTTY|O_APPEND*/ 0x700); if (res != -1) r[0] = res; // ioctl$DVB_DEMUX_DMX_SET_PES_FILTER arguments: [ // fd: fd_dvb_demux (resource) // cmd: const = 0x40146f2c (4 bytes) // arg: ptr[in, dmx_pes_filter_params] { // dmx_pes_filter_params { // pid: int16 = 0xefb8 (2 bytes) // pad = 0x0 (2 bytes) // input: dmx_input = 0x1 (4 bytes) // output: dmx_output = 0x2 (4 bytes) // pes_type: dmx_ts_pes = 0x3 (4 bytes) // flags: dmx_pes_filter_flags = 0x4 (4 bytes) // } // } // ] *(uint16_t*)0x200000000000 = 0xefb8; *(uint32_t*)0x200000000004 = 1; *(uint32_t*)0x200000000008 = 2; *(uint32_t*)0x20000000000c = 3; *(uint32_t*)0x200000000010 = 4; syscall(__NR_ioctl, /*fd=*/r[0], /*cmd=*/0x40146f2c, /*arg=*/0x200000000000ul); } int main(void) { syscall(__NR_mmap, /*addr=*/0x1ffffffff000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x200000000000ul, /*len=*/0x1000000ul, /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x200001000000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); const char* reason; (void)reason; loop(); return 0; }