From bd7570628066df4ad86ea4efdb1abb44338c3b99 Mon Sep 17 00:00:00 2001 From: Dmitry Vyukov Date: Thu, 17 Dec 2015 17:30:30 +0100 Subject: add a flag to disable setpgid syscall It is broken on some of our test systems. --- executor/executor.cc | 92 ++++++++++++++++++++++++++-------------------------- 1 file changed, 46 insertions(+), 46 deletions(-) (limited to 'executor') diff --git a/executor/executor.cc b/executor/executor.cc index 1ac518f3f..4d04c4fb9 100644 --- a/executor/executor.cc +++ b/executor/executor.cc @@ -68,6 +68,7 @@ bool flag_threaded; bool flag_collide; bool flag_deduplicate; bool flag_drop_privs; +bool flag_no_setpgid; __attribute__((aligned(64 << 10))) char input_data[kMaxInput]; __attribute__((aligned(64 << 10))) char output_data[kMaxOutput]; @@ -99,7 +100,7 @@ struct thread_t { int num_args; uint64_t args[kMaxArgs]; uint64_t res; - uint64_t errno; + uint64_t reserrno; uint32_t cover_size; int cover_fd; }; @@ -157,8 +158,9 @@ int main() flag_collide = flags & (1 << 3); flag_deduplicate = flags & (1 << 4); flag_drop_privs = flags & (1 << 5); - if (flag_collide) - flag_threaded = true; + flag_no_setpgid = flags & (1 << 6); + if (!flag_threaded) + flag_collide = false; cover_open(); @@ -175,7 +177,8 @@ int main() if (pid < 0) fail("fork failed"); if (pid == 0) { - setpgid(0, 0); + if (!flag_no_setpgid) + setpgid(0, 0); unshare(CLONE_NEWNS); close(kInPipeFd); close(kOutPipeFd); @@ -209,46 +212,48 @@ int main() } int status = 0; -#if 1 - timespec ts = {}; - ts.tv_sec = 5; - ts.tv_nsec = 0; - if (sigtimedwait(&sigchldset, NULL, &ts) < 0) { - debug("sigtimedwait expired, killing %d\n", pid); - kill(-pid, SIGKILL); - kill(pid, SIGKILL); - } - debug("waitpid(%d)\n", pid); - if (waitpid(pid, &status, __WALL | WUNTRACED) != pid) - fail("waitpid failed"); - debug("waitpid(%d) returned\n", pid); - // Drain SIGCHLD signals. - ts.tv_sec = 0; - ts.tv_nsec = 0; - while (sigtimedwait(&sigchldset, NULL, &ts) > 0) { - } -#else - // This code is less efficient, but does not require working sigtimedwait. - // We've hit 2 systems that mishandle sigtimedwait. - uint64_t start = current_time_ms(); - for (;;) { - int res = waitpid(pid, &status, __WALL | WUNTRACED | WNOHANG); - debug("waitpid(%d)=%d (%d)\n", pid, res, errno); - if (res == pid) - break; - usleep(1000); - if (current_time_ms() - start > 5 * 1000) { - debug("killing\n"); - kill(-pid, SIGKILL); + if (!flag_no_setpgid) { + timespec ts = {}; + ts.tv_sec = 5; + ts.tv_nsec = 0; + if (sigtimedwait(&sigchldset, NULL, &ts) < 0) { + debug("sigtimedwait expired, killing %d\n", pid); + if (!flag_no_setpgid) + kill(-pid, SIGKILL); kill(pid, SIGKILL); - int res = waitpid(pid, &status, __WALL | WUNTRACED); + } + debug("waitpid(%d)\n", pid); + if (waitpid(pid, &status, __WALL | WUNTRACED) != pid) + fail("waitpid failed"); + debug("waitpid(%d) returned\n", pid); + // Drain SIGCHLD signals. + ts.tv_sec = 0; + ts.tv_nsec = 0; + while (sigtimedwait(&sigchldset, NULL, &ts) > 0) { + } + } + else { + // This code is less efficient, but does not require working sigtimedwait. + // We've hit 2 systems that mishandle sigtimedwait. + uint64_t start = current_time_ms(); + for (;;) { + int res = waitpid(pid, &status, __WALL | WUNTRACED | WNOHANG); debug("waitpid(%d)=%d (%d)\n", pid, res, errno); if (res == pid) break; - fail("waitpid failed"); + usleep(1000); + if (current_time_ms() - start > 5 * 1000) { + debug("killing\n"); + kill(-pid, SIGKILL); + kill(pid, SIGKILL); + int res = waitpid(pid, &status, __WALL | WUNTRACED); + debug("waitpid(%d)=%d (%d)\n", pid, res, errno); + if (res == pid) + break; + fail("waitpid failed"); + } } } -#endif status = WEXITSTATUS(status); if (status == kFailStatus) fail("child failed"); @@ -503,7 +508,7 @@ void handle_completion(thread_t* th) write_output(th->call_index); write_output(th->call_num); - write_output(th->res != -1 ? 0 : th->errno); + write_output(th->res != (uint64_t)-1 ? 0 : th->reserrno); write_output(th->cover_size); for (uint32_t i = 0; i < th->cover_size; i++) write_output(th->cover_data[i + 1]); @@ -558,7 +563,6 @@ void execute_call(thread_t* th) if (th->num_args > 6) fail("bad number of arguments"); th->res = syscall(call->sys_nr, th->args[0], th->args[1], th->args[2], th->args[3], th->args[4], th->args[5]); - th->errno = errno; break; } case __NR_syz_openpts: { @@ -572,14 +576,12 @@ void execute_call(thread_t* th) else { th->res = -1; } - th->errno = errno; } case __NR_syz_dri_open: { // syz_dri_open(card_id intptr, flags flags[open_flags]) fd[dri] char buf[128]; sprintf(buf, "/dev/dri/card%lu", th->args[0]); th->res = open(buf, th->args[1], 0); - th->errno = errno; } case __NR_syz_fuse_mount: { // syz_fuse_mount(target filename, mode flags[fuse_mode], uid uid, gid gid, maxread intptr, flags flags[mount_flags]) fd[fuse] @@ -604,7 +606,6 @@ void execute_call(thread_t* th) // Ignore errors, maybe fuzzer can do something useful with fd alone. } th->res = fd; - th->errno = errno; } case __NR_syz_fuseblk_mount: { // syz_fuseblk_mount(target filename, blkdev filename, mode flags[fuse_mode], uid uid, gid gid, maxread intptr, blksize intptr, flags flags[mount_flags]) fd[fuse] @@ -635,14 +636,13 @@ void execute_call(thread_t* th) } } th->res = fd; - th->errno = errno; } } - int errno0 = errno; + th->reserrno = errno; th->cover_size = cover_read(th); if (th->res == (uint64_t)-1) - debug("#%d: %s = errno(%d)\n", th->id, call->name, errno0); + debug("#%d: %s = errno(%d)\n", th->id, call->name, th->reserrno); else debug("#%d: %s = 0x%lx\n", th->id, call->name, th->res); __atomic_store_n(&th->done, 1, __ATOMIC_RELEASE); -- cgit mrf-deployment