| // BUG: unable to handle kernel paging request in dput |
| // https://syzkaller.appspot.com/bug?id=f4fe17872e4fafefea02423216274aa494333720 |
| // status:fixed |
| // autogenerated by syzkaller (http://github.com/google/syzkaller) |
| |
| #define _GNU_SOURCE |
| #include <endian.h> |
| #include <errno.h> |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <fcntl.h> |
| #include <fcntl.h> |
| #include <stdarg.h> |
| #include <stdbool.h> |
| #include <stdio.h> |
| #include <stdio.h> |
| #include <string.h> |
| #include <sys/stat.h> |
| #include <sys/stat.h> |
| #include <sys/stat.h> |
| #include <sys/syscall.h> |
| #include <sys/types.h> |
| #include <unistd.h> |
| |
| __attribute__((noreturn)) static void doexit(int status) |
| { |
| volatile unsigned i; |
| syscall(__NR_exit_group, status); |
| for (i = 0;; i++) { |
| } |
| } |
| #include <errno.h> |
| #include <stdarg.h> |
| #include <stdint.h> |
| #include <stdio.h> |
| #include <string.h> |
| |
| 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; |
| } |
| |
| uint64_t r[1] = {0xffffffffffffffff}; |
| void loop() |
| { |
| long res = 0; |
| memcpy((void*)0x20000840, "ns", 3); |
| res = syz_open_procfs(0, 0x20000840); |
| if (res != -1) |
| r[0] = res; |
| 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_getdents64, r[0], 0x20000100, 0xa6); |
| } |
| |
| int main() |
| { |
| syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); |
| loop(); |
| return 0; |
| } |