| // WARNING: lock held when returning to user space in set_property_atomic |
| // https://syzkaller.appspot.com/bug?id=8523393d484b5e5c84cfc18030b080fabec02a24 |
| // status:fixed |
| // autogenerated by syzkaller (https://github.com/google/syzkaller) |
| |
| #define _GNU_SOURCE |
| |
| #include <endian.h> |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <setjmp.h> |
| #include <signal.h> |
| #include <stdarg.h> |
| #include <stdbool.h> |
| #include <stdint.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/stat.h> |
| #include <sys/syscall.h> |
| #include <sys/types.h> |
| #include <unistd.h> |
| |
| static __thread int skip_segv; |
| static __thread jmp_buf segv_env; |
| |
| static void segv_handler(int sig, siginfo_t* info, void* ctx) |
| { |
| uintptr_t addr = (uintptr_t)info->si_addr; |
| const uintptr_t prog_start = 1 << 20; |
| const uintptr_t prog_end = 100 << 20; |
| if (__atomic_load_n(&skip_segv, __ATOMIC_RELAXED) && |
| (addr < prog_start || addr > prog_end)) { |
| _longjmp(segv_env, 1); |
| } |
| exit(sig); |
| } |
| |
| static void install_segv_handler(void) |
| { |
| struct sigaction sa; |
| memset(&sa, 0, sizeof(sa)); |
| sa.sa_handler = SIG_IGN; |
| syscall(SYS_rt_sigaction, 0x20, &sa, NULL, 8); |
| syscall(SYS_rt_sigaction, 0x21, &sa, NULL, 8); |
| memset(&sa, 0, sizeof(sa)); |
| sa.sa_sigaction = segv_handler; |
| sa.sa_flags = SA_NODEFER | SA_SIGINFO; |
| sigaction(SIGSEGV, &sa, NULL); |
| sigaction(SIGBUS, &sa, NULL); |
| } |
| |
| #define NONFAILING(...) \ |
| { \ |
| __atomic_fetch_add(&skip_segv, 1, __ATOMIC_SEQ_CST); \ |
| if (_setjmp(segv_env) == 0) { \ |
| __VA_ARGS__; \ |
| } \ |
| __atomic_fetch_sub(&skip_segv, 1, __ATOMIC_SEQ_CST); \ |
| } |
| |
| static void use_temporary_dir(void) |
| { |
| char tmpdir_template[] = "./syzkaller.XXXXXX"; |
| char* tmpdir = mkdtemp(tmpdir_template); |
| if (!tmpdir) |
| exit(1); |
| if (chmod(tmpdir, 0777)) |
| exit(1); |
| if (chdir(tmpdir)) |
| exit(1); |
| } |
| |
| static long syz_open_dev(long a0, long a1, 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 { |
| char buf[1024]; |
| char* hash; |
| NONFAILING(strncpy(buf, (char*)a0, sizeof(buf) - 1)); |
| buf[sizeof(buf) - 1] = 0; |
| while ((hash = strchr(buf, '#'))) { |
| *hash = '0' + (char)(a1 % 10); |
| a1 /= 10; |
| } |
| return open(buf, a2, 0); |
| } |
| } |
| |
| 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) |
| exit(1); |
| sprintf(buf, "%d", nth + 1); |
| if (write(fd, buf, strlen(buf)) != (ssize_t)strlen(buf)) |
| exit(1); |
| return fd; |
| } |
| |
| uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff}; |
| |
| int main(void) |
| { |
| syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); |
| install_segv_handler(); |
| use_temporary_dir(); |
| long res = 0; |
| NONFAILING(memcpy((void*)0x200000c0, "/dev/dri/card#\x00", 15)); |
| res = syz_open_dev(0x200000c0, 1, 0); |
| if (res != -1) |
| r[0] = res; |
| res = syscall(__NR_dup, r[0]); |
| if (res != -1) |
| r[1] = res; |
| NONFAILING(*(uint64_t*)0x20000000 = 0); |
| NONFAILING(*(uint64_t*)0x20000008 = 0x2000000005); |
| 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_ioctl, r[1], 0x4010aeab, 0x20000000); |
| return 0; |
| } |