// https://syzkaller.appspot.com/bug?id=c905c82285226236abc44f3140e9290e96374cab // 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 #ifndef __NR_bpf #define __NR_bpf 321 #endif 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; } #define BITMASK(bf_off, bf_len) (((1ull << (bf_len)) - 1) << (bf_off)) #define STORE_BY_BITMASK(type, htobe, addr, val, bf_off, bf_len) \ *(type*)(addr) = \ htobe((htobe(*(type*)(addr)) & ~BITMASK((bf_off), (bf_len))) | \ (((type)(val) << (bf_off)) & BITMASK((bf_off), (bf_len)))) 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 setup_sysctl() { char mypid[32]; snprintf(mypid, sizeof(mypid), "%d", getpid()); struct { const char* name; const char* data; } files[] = { {"/sys/kernel/debug/x86/nmi_longest_ns", "10000000000"}, {"/proc/sys/kernel/hung_task_check_interval_secs", "20"}, {"/proc/sys/net/core/bpf_jit_kallsyms", "1"}, {"/proc/sys/net/core/bpf_jit_harden", "0"}, {"/proc/sys/kernel/kptr_restrict", "0"}, {"/proc/sys/kernel/softlockup_all_cpu_backtrace", "1"}, {"/proc/sys/fs/mount-max", "100"}, {"/proc/sys/vm/oom_dump_tasks", "0"}, {"/proc/sys/debug/exception-trace", "0"}, {"/proc/sys/kernel/printk", "7 4 1 3"}, {"/proc/sys/kernel/keys/gc_delay", "1"}, {"/proc/sys/vm/oom_kill_allocating_task", "1"}, {"/proc/sys/kernel/ctrl-alt-del", "0"}, {"/proc/sys/kernel/cad_pid", mypid}, }; for (size_t i = 0; i < sizeof(files) / sizeof(files[0]); i++) { if (!write_file(files[i].name, files[i].data)) printf("write to %s failed: %s\n", files[i].name, strerror(errno)); } } 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 (;;) { if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) break; sleep_ms(1); if (current_time_ms() - start < 5000) continue; kill_and_wait(pid, &status); break; } } } uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff}; void execute_one(void) { intptr_t res = 0; *(uint32_t*)0x200001c0 = 0x12; *(uint32_t*)0x200001c4 = 6; *(uint32_t*)0x200001c8 = 8; *(uint32_t*)0x200001cc = 2; *(uint32_t*)0x200001d0 = 0; *(uint32_t*)0x200001d4 = -1; *(uint32_t*)0x200001d8 = 0; memset((void*)0x200001dc, 0, 16); *(uint32_t*)0x200001ec = 0; *(uint32_t*)0x200001f0 = -1; *(uint32_t*)0x200001f4 = 0; *(uint32_t*)0x200001f8 = 0; *(uint32_t*)0x200001fc = 0; *(uint64_t*)0x20000200 = 0; res = syscall(__NR_bpf, /*cmd=*/0ul, /*arg=*/0x200001c0ul, /*size=*/0x48ul); if (res != -1) r[0] = res; *(uint32_t*)0x200007c0 = 0x11; *(uint32_t*)0x200007c4 = 0xc; *(uint64_t*)0x200007c8 = 0x20000740; *(uint8_t*)0x20000740 = 0x18; STORE_BY_BITMASK(uint8_t, , 0x20000741, 0, 0, 4); STORE_BY_BITMASK(uint8_t, , 0x20000741, 0, 4, 4); *(uint16_t*)0x20000742 = 0; *(uint32_t*)0x20000744 = 0; *(uint8_t*)0x20000748 = 0; *(uint8_t*)0x20000749 = 0; *(uint16_t*)0x2000074a = 0; *(uint32_t*)0x2000074c = 0; *(uint8_t*)0x20000750 = 0x18; STORE_BY_BITMASK(uint8_t, , 0x20000751, 1, 0, 4); STORE_BY_BITMASK(uint8_t, , 0x20000751, 1, 4, 4); *(uint16_t*)0x20000752 = 0; *(uint32_t*)0x20000754 = r[0]; *(uint8_t*)0x20000758 = 0; *(uint8_t*)0x20000759 = 0; *(uint16_t*)0x2000075a = 0; *(uint32_t*)0x2000075c = 0; STORE_BY_BITMASK(uint8_t, , 0x20000760, 7, 0, 3); STORE_BY_BITMASK(uint8_t, , 0x20000760, 0, 3, 1); STORE_BY_BITMASK(uint8_t, , 0x20000760, 0xb, 4, 4); STORE_BY_BITMASK(uint8_t, , 0x20000761, 8, 0, 4); STORE_BY_BITMASK(uint8_t, , 0x20000761, 0, 4, 4); *(uint16_t*)0x20000762 = 0; *(uint32_t*)0x20000764 = 0; STORE_BY_BITMASK(uint8_t, , 0x20000768, 3, 0, 3); STORE_BY_BITMASK(uint8_t, , 0x20000768, 3, 3, 2); STORE_BY_BITMASK(uint8_t, , 0x20000768, 3, 5, 3); STORE_BY_BITMASK(uint8_t, , 0x20000769, 0xa, 0, 4); STORE_BY_BITMASK(uint8_t, , 0x20000769, 8, 4, 4); *(uint16_t*)0x2000076a = 0xfff8; *(uint32_t*)0x2000076c = 0; STORE_BY_BITMASK(uint8_t, , 0x20000770, 7, 0, 3); STORE_BY_BITMASK(uint8_t, , 0x20000770, 1, 3, 1); STORE_BY_BITMASK(uint8_t, , 0x20000770, 0xb, 4, 4); STORE_BY_BITMASK(uint8_t, , 0x20000771, 2, 0, 4); STORE_BY_BITMASK(uint8_t, , 0x20000771, 0xa, 4, 4); *(uint16_t*)0x20000772 = 0; *(uint32_t*)0x20000774 = 0; STORE_BY_BITMASK(uint8_t, , 0x20000778, 7, 0, 3); STORE_BY_BITMASK(uint8_t, , 0x20000778, 0, 3, 1); STORE_BY_BITMASK(uint8_t, , 0x20000778, 0, 4, 4); STORE_BY_BITMASK(uint8_t, , 0x20000779, 2, 0, 4); STORE_BY_BITMASK(uint8_t, , 0x20000779, 0, 4, 4); *(uint16_t*)0x2000077a = 0; *(uint32_t*)0x2000077c = 0xfffffff8; STORE_BY_BITMASK(uint8_t, , 0x20000780, 7, 0, 3); STORE_BY_BITMASK(uint8_t, , 0x20000780, 0, 3, 1); STORE_BY_BITMASK(uint8_t, , 0x20000780, 0xb, 4, 4); STORE_BY_BITMASK(uint8_t, , 0x20000781, 3, 0, 4); STORE_BY_BITMASK(uint8_t, , 0x20000781, 0, 4, 4); *(uint16_t*)0x20000782 = 0; *(uint32_t*)0x20000784 = 8; STORE_BY_BITMASK(uint8_t, , 0x20000788, 7, 0, 3); STORE_BY_BITMASK(uint8_t, , 0x20000788, 0, 3, 1); STORE_BY_BITMASK(uint8_t, , 0x20000788, 0xb, 4, 4); STORE_BY_BITMASK(uint8_t, , 0x20000789, 4, 0, 4); STORE_BY_BITMASK(uint8_t, , 0x20000789, 0, 4, 4); *(uint16_t*)0x2000078a = 0; *(uint32_t*)0x2000078c = 0; *(uint8_t*)0x20000790 = 0x85; *(uint8_t*)0x20000791 = 0; *(uint16_t*)0x20000792 = 0; *(uint32_t*)0x20000794 = 3; *(uint8_t*)0x20000798 = 0x95; *(uint8_t*)0x20000799 = 0; *(uint16_t*)0x2000079a = 0; *(uint32_t*)0x2000079c = 0; *(uint64_t*)0x200007d0 = 0x20000240; memcpy((void*)0x20000240, "syzkaller\000", 10); *(uint32_t*)0x200007d8 = 0; *(uint32_t*)0x200007dc = 0; *(uint64_t*)0x200007e0 = 0; *(uint32_t*)0x200007e8 = 0; *(uint32_t*)0x200007ec = 0; memset((void*)0x200007f0, 0, 16); *(uint32_t*)0x20000800 = 0; *(uint32_t*)0x20000804 = 0; *(uint32_t*)0x20000808 = -1; *(uint32_t*)0x2000080c = 0; *(uint64_t*)0x20000810 = 0; *(uint32_t*)0x20000818 = 0; *(uint32_t*)0x2000081c = 0; *(uint64_t*)0x20000820 = 0; *(uint32_t*)0x20000828 = 0; *(uint32_t*)0x2000082c = 0; *(uint32_t*)0x20000830 = 0; *(uint32_t*)0x20000834 = 0; *(uint64_t*)0x20000838 = 0; *(uint64_t*)0x20000840 = 0; *(uint32_t*)0x20000848 = 0; *(uint32_t*)0x2000084c = 0; res = syscall(__NR_bpf, /*cmd=*/5ul, /*arg=*/0x200007c0ul, /*size=*/0x90ul); if (res != -1) r[1] = res; *(uint64_t*)0x20000b40 = 0x20000b00; memcpy((void*)0x20000b00, "sched_switch\000", 13); *(uint32_t*)0x20000b48 = r[1]; syscall(__NR_bpf, /*cmd=*/0x11ul, /*arg=*/0x20000b40ul, /*size=*/0x10ul); } int main(void) { syscall(__NR_mmap, /*addr=*/0x1ffff000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x20000000ul, /*len=*/0x1000000ul, /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x21000000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1, /*offset=*/0ul); setup_sysctl(); loop(); return 0; }