// https://syzkaller.appspot.com/bug?id=401730da81cc65b97da6fa48aa9c0d392463f1b5 // autogenerated by syzkaller (http://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include __attribute__((noreturn)) static void doexit(int status) { volatile unsigned i; syscall(__NR_exit_group, status); for (i = 0;; i++) { } } #include #include #include #include #include const int kFailStatus = 67; const int kRetryStatus = 69; static void exitf(const char* msg, ...) { int e = errno; va_list args; va_start(args, msg); vfprintf(stderr, msg, args); va_end(args); fprintf(stderr, " (errno %d)\n", e); doexit(kRetryStatus); } static uintptr_t syz_open_procfs(uintptr_t a0, uintptr_t a1) { char buf[128]; memset(buf, 0, sizeof(buf)); if (a0 == 0) { snprintf(buf, sizeof(buf), "/proc/self/%s", (char*)a1); } else if (a0 == (uintptr_t)-1) { snprintf(buf, sizeof(buf), "/proc/thread-self/%s", (char*)a1); } else { snprintf(buf, sizeof(buf), "/proc/self/task/%d/%s", (int)a0, (char*)a1); } int fd = open(buf, O_RDWR); if (fd == -1) fd = open(buf, O_RDONLY); return fd; } 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 int inject_fault(int nth) { int fd; char buf[16]; fd = open("/proc/thread-self/fail-nth", O_RDWR); if (fd == -1) exitf("failed to open /proc/thread-self/fail-nth"); sprintf(buf, "%d", nth + 1); if (write(fd, buf, strlen(buf)) != (ssize_t)strlen(buf)) exitf("failed to write /proc/thread-self/fail-nth"); return fd; } static void execute_one(); extern unsigned long long procid; void loop() { while (1) { execute_one(); } } uint64_t r[1] = {0xffffffffffffffff}; unsigned long long procid; void execute_one() { long res = 0; memcpy((void*)0x20b92000, "smaps", 6); res = syz_open_procfs(0, 0x20b92000); if (res != -1) r[0] = res; *(uint64_t*)0x209a5f80 = 0x20214000; *(uint64_t*)0x209a5f88 = 0x1000; syscall(__NR_readv, r[0], 0x209a5f80, 1); syscall(__NR_clone, 0, 0x20001140, 0x20001200, 0x20001280, 0x200012c0); *(uint64_t*)0x20dc8ff8 = 0x20208000; *(uint64_t*)0x20dc9000 = 0x1000; write_file("/sys/kernel/debug/failslab/ignore-gfp-wait", "N"); write_file("/sys/kernel/debug/fail_futex/ignore-private", "N"); inject_fault(0); syscall(__NR_readv, r[0], 0x20dc8ff8, 0x1d3); } int main() { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); for (procid = 0; procid < 8; procid++) { if (fork() == 0) { for (;;) { loop(); } } } sleep(1000000); return 0; }