// https://syzkaller.appspot.com/bug?id=0b210638616bb68109e9642158d4c0072770ae1c // 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 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)) { } // openat$smackfs_ambient arguments: [ // fd: const = 0xffffffffffffff9c (8 bytes) // file: ptr[in, buffer] { // buffer: {2f 73 79 73 2f 66 73 2f 73 6d 61 63 6b 66 73 2f 61 6d 62 69 // 65 6e 74 00} (length 0x18) // } // flags: const = 0x2 (4 bytes) // mode: const = 0x0 (2 bytes) // ] // returns fd_smackfs_label memcpy((void*)0x200000000000, "/sys/fs/smackfs/ambient\000", 24); res = syscall(__NR_openat, /*fd=*/0xffffffffffffff9cul, /*file=*/0x200000000000ul, /*flags=*/2, /*mode=*/0); if (res != -1) r[0] = res; // write$smackfs_label arguments: [ // fd: fd_smackfs_label (resource) // buf: ptr[inout, array[ANYUNION]] { // array[ANYUNION] { // union ANYUNION { // ANYBLOB: buffer: {39 f3 4f 65 04 00 54 db c2 43 6a 37 e0 09 eb 56 // 81 af 8a ce 86 41 0b cb 73 3c 7a dc df 51 88 59 ea f6 eb 7b 84 e7 // 3f 1c} (length 0x28) // } // } // } // count: len = 0x1 (8 bytes) // ] memcpy((void*)0x2000000000c0, "\x39\xf3\x4f\x65\x04\x00\x54\xdb\xc2\x43\x6a\x37\xe0\x09\xeb\x56\x81" "\xaf\x8a\xce\x86\x41\x0b\xcb\x73\x3c\x7a\xdc\xdf\x51\x88\x59\xea\xf6" "\xeb\x7b\x84\xe7\x3f\x1c", 40); syscall(__NR_write, /*fd=*/r[0], /*buf=*/0x2000000000c0ul, /*count=*/1ul); } 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; }