Messages in this thread | | | From | Andrey Konovalov <> | Date | Wed, 12 Apr 2017 17:02:15 +0200 | Subject | ney/key: slab-out-of-bounds in parse_ipsecrequests |
| |
Hi,
I've got the following error report while fuzzing the kernel with syzkaller.
On commit 39da7c509acff13fc8cb12ec1bb20337c988ed36 (4.11-rc6).
A reproducer and .config are attached.
When subtracting rq->sadb_x_ipsecrequest_len from len it can become negative and the while loop condition remains true.
================================================================== BUG: KASAN: slab-out-of-bounds in parse_ipsecrequest net/key/af_key.c:1897 [inline] at addr ffff88006b1e3d0b BUG: KASAN: slab-out-of-bounds in parse_ipsecrequests+0xc89/0xdc0 net/key/af_key.c:1949 at addr ffff88006b1e3d0b Read of size 1 by task syz-executor5/11796 CPU: 2 PID: 11796 Comm: syz-executor5 Not tainted 4.11.0-rc6+ #211 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x292/0x398 lib/dump_stack.c:52 kasan_object_err+0x1c/0x70 mm/kasan/report.c:164 print_address_description mm/kasan/report.c:202 [inline] kasan_report_error mm/kasan/report.c:291 [inline] kasan_report+0x252/0x510 mm/kasan/report.c:347 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:365 parse_ipsecrequest net/key/af_key.c:1897 [inline] parse_ipsecrequests+0xc89/0xdc0 net/key/af_key.c:1949 pfkey_compile_policy+0xa20/0xd40 net/key/af_key.c:3241 xfrm_user_policy+0x34c/0x560 net/xfrm/xfrm_state.c:1892 do_ip_setsockopt.isra.12+0x1afa/0x36c0 net/ipv4/ip_sockglue.c:1175 ip_setsockopt+0x3a/0xb0 net/ipv4/ip_sockglue.c:1264 tcp_setsockopt+0x82/0xd0 net/ipv4/tcp.c:2731 sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2750 SYSC_setsockopt net/socket.c:1798 [inline] SyS_setsockopt+0x270/0x3a0 net/socket.c:1777 entry_SYSCALL_64_fastpath+0x1f/0xc2 RIP: 0033:0x4458d9 RSP: 002b:00007f319fffdb58 EFLAGS: 00000292 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00000000004458d9 RDX: 0000000000000010 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 00000000006e3560 R08: 00000000000000e8 R09: 0000000000000000 R10: 0000000020002000 R11: 0000000000000292 R12: 0000000000708000 R13: 0000000000000000 R14: 00007f319fffe9c0 R15: 00007f319fffe700 Object at ffff88006b1e3b28, in cache kernfs_node_cache size: 152 Allocated: PID = 1 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:513 set_track mm/kasan/kasan.c:525 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:616 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:555 slab_post_alloc_hook mm/slab.h:456 [inline] slab_alloc_node mm/slub.c:2718 [inline] slab_alloc mm/slub.c:2726 [inline] kmem_cache_alloc+0x1af/0x250 mm/slub.c:2731 kmem_cache_zalloc include/linux/slab.h:653 [inline] __kernfs_new_node+0xd1/0x3e0 fs/kernfs/dir.c:629 kernfs_new_node+0x80/0xe0 fs/kernfs/dir.c:661 __kernfs_create_file+0x4b/0x320 fs/kernfs/file.c:989 sysfs_add_file_mode_ns+0x220/0x520 fs/sysfs/file.c:307 create_files fs/sysfs/group.c:64 [inline] internal_create_group+0x239/0x8f0 fs/sysfs/group.c:134 sysfs_create_group+0x1f/0x30 fs/sysfs/group.c:156 sysfs_slab_add+0x1d0/0x200 mm/slub.c:5659 __kmem_cache_create+0x428/0x4c0 mm/slub.c:4253 create_cache mm/slab_common.c:382 [inline] kmem_cache_create+0x15d/0x240 mm/slab_common.c:467 jbd2_journal_init_revoke_caches+0x8a/0xaf fs/jbd2/revoke.c:206 journal_init_caches fs/jbd2/journal.c:2631 [inline] journal_init+0xf/0x14d fs/jbd2/journal.c:2656 do_one_initcall+0xf3/0x390 init/main.c:792 do_initcall_level init/main.c:858 [inline] do_initcalls init/main.c:866 [inline] do_basic_setup init/main.c:884 [inline] kernel_init_freeable+0x5d1/0x6a6 init/main.c:1035 kernel_init+0x13/0x180 init/main.c:959 ret_from_fork+0x31/0x40 arch/x86/entry/entry_64.S:430 Freed: PID = 0 (stack is not available) Memory state around the buggy address: ffff88006b1e3c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88006b1e3c80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88006b1e3d00: fc fc fc 00 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff88006b1e3d80: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc ffff88006b1e3e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== // autogenerated by syzkaller (http://github.com/google/syzkaller)
#ifndef __NR_mmap #define __NR_mmap 9 #endif #ifndef __NR_socket #define __NR_socket 41 #endif #ifndef __NR_ioctl #define __NR_ioctl 16 #endif #ifndef __NR_setsockopt #define __NR_setsockopt 54 #endif
#define _GNU_SOURCE
#include <sys/ioctl.h> #include <sys/mman.h> #include <sys/mount.h> #include <sys/prctl.h> #include <sys/resource.h> #include <sys/socket.h> #include <sys/stat.h> #include <sys/syscall.h> #include <sys/time.h> #include <sys/types.h> #include <sys/wait.h>
#include <linux/capability.h> #include <linux/if.h> #include <linux/if_tun.h> #include <linux/kvm.h> #include <linux/sched.h> #include <net/if_arp.h>
#include <assert.h> #include <dirent.h> #include <errno.h> #include <fcntl.h> #include <grp.h> #include <pthread.h> #include <setjmp.h> #include <signal.h> #include <stdarg.h> #include <stdbool.h> #include <stddef.h> #include <stdint.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h>
const int kFailStatus = 67; const int kErrorStatus = 68; const int kRetryStatus = 69;
__attribute__((noreturn)) void doexit(int status) { volatile unsigned i; syscall(__NR_exit_group, status); for (i = 0;; i++) { } }
__attribute__((noreturn)) void fail(const char* msg, ...) { int e = errno; fflush(stdout); va_list args; va_start(args, msg); vfprintf(stderr, msg, args); va_end(args); fprintf(stderr, " (errno %d)\n", e); doexit((e == ENOMEM || e == EAGAIN) ? kRetryStatus : kFailStatus); }
__attribute__((noreturn)) void exitf(const char* msg, ...) { int e = errno; fflush(stdout); va_list args; va_start(args, msg); vfprintf(stderr, msg, args); va_end(args); fprintf(stderr, " (errno %d)\n", e); doexit(kRetryStatus); }
static int flag_debug;
void debug(const char* msg, ...) { if (!flag_debug) return; va_list args; va_start(args, msg); vfprintf(stdout, msg, args); va_end(args); fflush(stdout); }
__thread int skip_segv; __thread jmp_buf segv_env;
static void segv_handler(int sig, siginfo_t* info, void* uctx) { 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)) { debug("SIGSEGV on %p, skipping\n", addr); _longjmp(segv_env, 1); } debug("SIGSEGV on %p, exiting\n", addr); doexit(sig); for (;;) { } }
static void install_segv_handler() { struct sigaction sa; 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); \ }
#define BITMASK_LEN(type, bf_len) (type)((1ull << (bf_len)) - 1)
#define BITMASK_LEN_OFF(type, bf_off, bf_len) \ (type)(BITMASK_LEN(type, (bf_len)) << (bf_off))
#define STORE_BY_BITMASK(type, addr, val, bf_off, bf_len) \ if ((bf_off) == 0 && (bf_len) == 0) { \ *(type*)(addr) = (type)(val); \ } else { \ type new_val = *(type*)(addr); \ new_val &= ~BITMASK_LEN_OFF(type, (bf_off), (bf_len)); \ new_val |= ((type)(val)&BITMASK_LEN(type, (bf_len))) << (bf_off); \ *(type*)(addr) = new_val; \ }
static uintptr_t execute_syscall(int nr, uintptr_t a0, uintptr_t a1, uintptr_t a2, uintptr_t a3, uintptr_t a4, uintptr_t a5, uintptr_t a6, uintptr_t a7, uintptr_t a8) { switch (nr) { default: return syscall(nr, a0, a1, a2, a3, a4, a5); } }
static void setup_main_process() { 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); install_segv_handler();
char tmpdir_template[] = "./syzkaller.XXXXXX"; char* tmpdir = mkdtemp(tmpdir_template); if (!tmpdir) fail("failed to mkdtemp"); if (chmod(tmpdir, 0777)) fail("failed to chmod"); if (chdir(tmpdir)) fail("failed to chdir"); }
static void loop();
static void sandbox_common() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); setsid();
struct rlimit rlim; rlim.rlim_cur = rlim.rlim_max = 128 << 20; setrlimit(RLIMIT_AS, &rlim); rlim.rlim_cur = rlim.rlim_max = 1 << 20; setrlimit(RLIMIT_FSIZE, &rlim); rlim.rlim_cur = rlim.rlim_max = 1 << 20; setrlimit(RLIMIT_STACK, &rlim); rlim.rlim_cur = rlim.rlim_max = 0; setrlimit(RLIMIT_CORE, &rlim);
unshare(CLONE_NEWNS); unshare(CLONE_NEWIPC); unshare(CLONE_IO); }
static int do_sandbox_none(int executor_pid, bool enable_tun) { int pid = fork(); if (pid) return pid;
sandbox_common();
loop(); doexit(1); }
static void remove_dir(const char* dir) { DIR* dp; struct dirent* ep; int iter = 0; retry: dp = opendir(dir); if (dp == NULL) { if (errno == EMFILE) { exitf("opendir(%s) failed due to NOFILE, exiting"); } exitf("opendir(%s) failed", dir); } while ((ep = readdir(dp))) { if (strcmp(ep->d_name, ".") == 0 || strcmp(ep->d_name, "..") == 0) continue; char filename[FILENAME_MAX]; snprintf(filename, sizeof(filename), "%s/%s", dir, ep->d_name); struct stat st; if (lstat(filename, &st)) exitf("lstat(%s) failed", filename); if (S_ISDIR(st.st_mode)) { remove_dir(filename); continue; } int i; for (i = 0;; i++) { debug("unlink(%s)\n", filename); if (unlink(filename) == 0) break; if (errno == EROFS) { debug("ignoring EROFS\n"); break; } if (errno != EBUSY || i > 100) exitf("unlink(%s) failed", filename); debug("umount(%s)\n", filename); if (umount2(filename, MNT_DETACH)) exitf("umount(%s) failed", filename); } } closedir(dp); int i; for (i = 0;; i++) { debug("rmdir(%s)\n", dir); if (rmdir(dir) == 0) break; if (i < 100) { if (errno == EROFS) { debug("ignoring EROFS\n"); break; } if (errno == EBUSY) { debug("umount(%s)\n", dir); if (umount2(dir, MNT_DETACH)) exitf("umount(%s) failed", dir); continue; } if (errno == ENOTEMPTY) { if (iter < 100) { iter++; goto retry; } } } exitf("rmdir(%s) failed", dir); } }
static uint64_t current_time_ms() { struct timespec ts;
if (clock_gettime(CLOCK_MONOTONIC, &ts)) fail("clock_gettime failed"); return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000; }
static void test();
void loop() { int iter; for (iter = 0;; iter++) { char cwdbuf[256]; sprintf(cwdbuf, "./%d", iter); if (mkdir(cwdbuf, 0777)) fail("failed to mkdir"); int pid = fork(); if (pid < 0) fail("clone failed"); if (pid == 0) { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); if (chdir(cwdbuf)) fail("failed to chdir"); test(); doexit(0); } int status = 0; uint64_t start = current_time_ms(); for (;;) { int res = waitpid(-1, &status, __WALL | WNOHANG); if (res == pid) break; usleep(1000); if (current_time_ms() - start > 5 * 1000) { kill(-pid, SIGKILL); kill(pid, SIGKILL); while (waitpid(-1, &status, __WALL) != pid) { } break; } } remove_dir(cwdbuf); } }
long r[106]; void test() { memset(r, -1, sizeof(r)); r[0] = execute_syscall(__NR_mmap, 0x20000000ul, 0xd4c000ul, 0x3ul, 0x32ul, 0xfffffffffffffffful, 0x0ul, 0, 0, 0); r[1] = execute_syscall(__NR_socket, 0x2ul, 0x1ul, 0x0ul, 0, 0, 0, 0, 0, 0); NONFAILING(*(uint16_t*)0x20002000 = (uint16_t)0x2); NONFAILING(*(uint16_t*)0x20002002 = (uint16_t)0x214e); NONFAILING(*(uint32_t*)0x20002004 = (uint32_t)0x1000000); NONFAILING(*(uint8_t*)0x20002008 = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x20002009 = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x2000200a = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x2000200b = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x2000200c = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x2000200d = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x2000200e = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x2000200f = (uint8_t)0x0); NONFAILING(*(uint16_t*)0x20002010 = (uint16_t)0x6); NONFAILING(memcpy((void*)0x20002012, "\x99\xba\x03\xfa\x05\x4a", 6)); NONFAILING(*(uint8_t*)0x20002018 = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x20002019 = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x2000201a = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x2000201b = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x2000201c = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x2000201d = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x2000201e = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x2000201f = (uint8_t)0x0); NONFAILING(*(uint32_t*)0x20002020 = (uint32_t)0x0); NONFAILING(*(uint16_t*)0x20002024 = (uint16_t)0x2); NONFAILING(*(uint16_t*)0x20002026 = (uint16_t)0x234e); NONFAILING(*(uint32_t*)0x20002028 = (uint32_t)0x20000e0); NONFAILING(*(uint8_t*)0x2000202c = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x2000202d = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x2000202e = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x2000202f = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x20002030 = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x20002031 = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x20002032 = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x20002033 = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x20002034 = (uint8_t)0x73); NONFAILING(*(uint8_t*)0x20002035 = (uint8_t)0x79); NONFAILING(*(uint8_t*)0x20002036 = (uint8_t)0x7a); NONFAILING(*(uint8_t*)0x20002037 = (uint8_t)0x30); NONFAILING(*(uint8_t*)0x20002038 = (uint8_t)0x0); r[40] = execute_syscall(__NR_ioctl, r[1], 0x8953ul, 0x20002000ul, 0, 0, 0, 0, 0, 0); NONFAILING(*(uint32_t*)0x20002000 = (uint32_t)0x9); NONFAILING(*(uint16_t*)0x20002004 = (uint16_t)0x2); NONFAILING(*(uint16_t*)0x20002006 = (uint16_t)0x2); NONFAILING(*(uint32_t*)0x20002008 = (uint32_t)0x4); NONFAILING(*(uint32_t*)0x2000200c = (uint32_t)0x81); NONFAILING(*(uint32_t*)0x20002010 = (uint32_t)0x2); r[47] = execute_syscall(__NR_setsockopt, 0xfffffffffffffffful, 0x84ul, 0x1ul, 0x20002000ul, 0x14ul, 0, 0, 0, 0); NONFAILING(*(uint32_t*)0x20002000 = (uint32_t)0x7000004); NONFAILING(*(uint32_t*)0x20002010 = (uint32_t)0xffffffff); NONFAILING(*(uint16_t*)0x20002020 = (uint16_t)0x224e); NONFAILING(*(uint16_t*)0x20002022 = (uint16_t)0xa7); NONFAILING(*(uint16_t*)0x20002024 = (uint16_t)0x204e); NONFAILING(*(uint16_t*)0x20002026 = (uint16_t)0x0); NONFAILING(*(uint16_t*)0x20002028 = (uint16_t)0x0); NONFAILING(*(uint8_t*)0x2000202a = (uint8_t)0x80000001); NONFAILING(*(uint8_t*)0x2000202b = (uint8_t)0x9); NONFAILING(*(uint8_t*)0x2000202c = (uint8_t)0x1); NONFAILING(*(uint32_t*)0x20002030 = (uint32_t)0x10001); NONFAILING(*(uint32_t*)0x20002034 = (uint32_t)0x51940); NONFAILING(*(uint64_t*)0x20002038 = (uint64_t)0x5); NONFAILING(*(uint64_t*)0x20002040 = (uint64_t)0x7); NONFAILING(*(uint64_t*)0x20002048 = (uint64_t)0xf58); NONFAILING(*(uint64_t*)0x20002050 = (uint64_t)0x77b3); NONFAILING(*(uint64_t*)0x20002058 = (uint64_t)0xffffffffffff8001); NONFAILING(*(uint64_t*)0x20002060 = (uint64_t)0xd13); NONFAILING(*(uint64_t*)0x20002068 = (uint64_t)0x2); NONFAILING(*(uint64_t*)0x20002070 = (uint64_t)0x3); NONFAILING(*(uint64_t*)0x20002078 = (uint64_t)0xa3); NONFAILING(*(uint64_t*)0x20002080 = (uint64_t)0xfffffffffffffffc); NONFAILING(*(uint64_t*)0x20002088 = (uint64_t)0x101); NONFAILING(*(uint64_t*)0x20002090 = (uint64_t)0x8001); NONFAILING(*(uint32_t*)0x20002098 = (uint32_t)0xfffffffffffffffd); NONFAILING(*(uint32_t*)0x2000209c = (uint32_t)0xfffffffffffffff8); NONFAILING(*(uint8_t*)0x200020a0 = (uint8_t)0x6); NONFAILING(*(uint8_t*)0x200020a1 = (uint8_t)0x1); NONFAILING(*(uint8_t*)0x200020a2 = (uint8_t)0x8); NONFAILING(*(uint8_t*)0x200020a3 = (uint8_t)0xffffffffffffffff); NONFAILING(*(uint8_t*)0x200020a8 = (uint8_t)0xfd); NONFAILING(*(uint8_t*)0x200020a9 = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x200020aa = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x200020ab = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x200020ac = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x200020ad = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x200020ae = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x200020af = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x200020b0 = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x200020b1 = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x200020b2 = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x200020b3 = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x200020b4 = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x200020b5 = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x200020b6 = (uint8_t)0x0); NONFAILING(*(uint8_t*)0x200020b7 = (uint8_t)0xaa); NONFAILING(*(uint32_t*)0x200020b8 = (uint32_t)0x83); NONFAILING(*(uint8_t*)0x200020bc = (uint8_t)0xffffffff7fffffff); NONFAILING(*(uint16_t*)0x200020c0 = (uint16_t)0x2); NONFAILING(*(uint32_t*)0x200020c4 = (uint32_t)0xffffffff); NONFAILING(*(uint32_t*)0x200020d4 = (uint32_t)0x4); NONFAILING(*(uint8_t*)0x200020d8 = (uint8_t)0x5); NONFAILING(*(uint8_t*)0x200020d9 = (uint8_t)0x40000000); NONFAILING(*(uint8_t*)0x200020da = (uint8_t)0x5); NONFAILING(*(uint32_t*)0x200020dc = (uint32_t)0x3); NONFAILING(*(uint32_t*)0x200020e0 = (uint32_t)0x1ff); NONFAILING(*(uint32_t*)0x200020e4 = (uint32_t)0x201); r[105] = execute_syscall(__NR_setsockopt, r[1], 0x0ul, 0x10ul, 0x20002000ul, 0xe8ul, 0, 0, 0, 0); } int main() { setup_main_process(); int pid = do_sandbox_none(0, false); int status = 0; while (waitpid(pid, &status, __WALL) != pid) { } return 0; } [unhandled content-type:application/octet-stream] | |