From db7feb7e9c436ec3ad3b90cf21bd43d8036aad0d Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Thu, 19 Jul 2012 02:03:42 +0200 Subject: [PATCH 1/1] nspawn: generate proper error messages in the child --- src/nspawn/nspawn.c | 60 +++++++++++++++++++++++++++++---------------- 1 file changed, 39 insertions(+), 21 deletions(-) diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c index 14de7f8b4..1d7511e2a 100644 --- a/src/nspawn/nspawn.c +++ b/src/nspawn/nspawn.c @@ -808,13 +808,15 @@ static int process_pty(int master, sigset_t *mask) { fd_nonblock(STDOUT_FILENO, 1); fd_nonblock(master, 1); - if ((signal_fd = signalfd(-1, mask, SFD_NONBLOCK|SFD_CLOEXEC)) < 0) { + signal_fd = signalfd(-1, mask, SFD_NONBLOCK|SFD_CLOEXEC); + if (signal_fd < 0) { log_error("signalfd(): %m"); r = -errno; goto finish; } - if ((ep = epoll_create1(EPOLL_CLOEXEC)) < 0) { + ep = epoll_create1(EPOLL_CLOEXEC); + if (ep < 0) { log_error("Failed to create epoll: %m"); r = -errno; goto finish; @@ -850,7 +852,8 @@ static int process_pty(int master, sigset_t *mask) { ssize_t k; int i, nfds; - if ((nfds = epoll_wait(ep, ev, ELEMENTSOF(ev), -1)) < 0) { + nfds = epoll_wait(ep, ev, ELEMENTSOF(ev), -1); + if (nfds < 0) { if (errno == EINTR || errno == EAGAIN) continue; @@ -885,7 +888,8 @@ static int process_pty(int master, sigset_t *mask) { struct signalfd_siginfo sfsi; ssize_t n; - if ((n = read(signal_fd, &sfsi, sizeof(sfsi))) != sizeof(sfsi)) { + n = read(signal_fd, &sfsi, sizeof(sfsi)); + if (n != sizeof(sfsi)) { if (n >= 0) { log_error("Failed to read from signalfd: invalid block size"); @@ -921,7 +925,8 @@ static int process_pty(int master, sigset_t *mask) { if (stdin_readable && in_buffer_full < LINE_MAX) { - if ((k = read(STDIN_FILENO, in_buffer + in_buffer_full, LINE_MAX - in_buffer_full)) < 0) { + k = read(STDIN_FILENO, in_buffer + in_buffer_full, LINE_MAX - in_buffer_full); + if (k < 0) { if (errno == EAGAIN || errno == EPIPE || errno == ECONNRESET || errno == EIO) stdin_readable = false; @@ -936,7 +941,8 @@ static int process_pty(int master, sigset_t *mask) { if (master_writable && in_buffer_full > 0) { - if ((k = write(master, in_buffer, in_buffer_full)) < 0) { + k = write(master, in_buffer, in_buffer_full); + if (k < 0) { if (errno == EAGAIN || errno == EPIPE || errno == ECONNRESET || errno == EIO) master_writable = false; @@ -955,7 +961,8 @@ static int process_pty(int master, sigset_t *mask) { if (master_readable && out_buffer_full < LINE_MAX) { - if ((k = read(master, out_buffer + out_buffer_full, LINE_MAX - out_buffer_full)) < 0) { + k = read(master, out_buffer + out_buffer_full, LINE_MAX - out_buffer_full); + if (k < 0) { if (errno == EAGAIN || errno == EPIPE || errno == ECONNRESET || errno == EIO) master_readable = false; @@ -970,7 +977,8 @@ static int process_pty(int master, sigset_t *mask) { if (stdout_writable && out_buffer_full > 0) { - if ((k = write(STDOUT_FILENO, out_buffer, out_buffer_full)) < 0) { + k = write(STDOUT_FILENO, out_buffer, out_buffer_full); + if (k < 0) { if (errno == EAGAIN || errno == EPIPE || errno == ECONNRESET || errno == EIO) stdout_writable = false; @@ -1015,7 +1023,8 @@ int main(int argc, char *argv[]) { log_parse_environment(); log_open(); - if ((r = parse_argv(argc, argv)) <= 0) + r = parse_argv(argc, argv); + if (r <= 0) goto finish; if (arg_directory) { @@ -1054,7 +1063,8 @@ int main(int argc, char *argv[]) { goto finish; } - if ((k = cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, 0, &oldcg)) < 0) { + k = cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, 0, &oldcg); + if (k < 0) { log_error("Failed to determine current cgroup: %s", strerror(-k)); goto finish; } @@ -1070,18 +1080,20 @@ int main(int argc, char *argv[]) { goto finish; } - STRV_FOREACH(controller,arg_controllers) { + STRV_FOREACH(controller, arg_controllers) { k = cg_create_and_attach(*controller, newcg, 0); if (k < 0) log_warning("Failed to create cgroup in controller %s: %s", *controller, strerror(-k)); } - if ((master = posix_openpt(O_RDWR|O_NOCTTY|O_CLOEXEC|O_NDELAY)) < 0) { + master = posix_openpt(O_RDWR|O_NOCTTY|O_CLOEXEC|O_NDELAY); + if (master < 0) { log_error("Failed to acquire pseudo tty: %m"); goto finish; } - if (!(console = ptsname(master))) { + console = ptsname(master); + if (!console) { log_error("Failed to determine tty name: %m"); goto finish; } @@ -1163,15 +1175,26 @@ int main(int argc, char *argv[]) { assert_se(sigemptyset(&mask) == 0); assert_se(sigprocmask(SIG_SETMASK, &mask, NULL) == 0); - if (setsid() < 0) + if (open_terminal(console, O_RDWR) != STDIN_FILENO || + dup2(STDIN_FILENO, STDOUT_FILENO) != STDOUT_FILENO || + dup2(STDIN_FILENO, STDERR_FILENO) != STDERR_FILENO) + goto child_fail; + + if (setsid() < 0) { + log_error("setsid() failed: %m"); goto child_fail; + } - if (prctl(PR_SET_PDEATHSIG, SIGKILL) < 0) + if (prctl(PR_SET_PDEATHSIG, SIGKILL) < 0) { + log_error("PR_SET_PDEATHSIG failed: %m"); goto child_fail; + } /* Mark / as private, in case somebody marked it shared */ - if (mount(NULL, "/", NULL, MS_PRIVATE|MS_REC, NULL) < 0) + if (mount(NULL, "/", NULL, MS_PRIVATE|MS_REC, NULL) < 0) { + log_error("MS_PRIVATE|MS_REC failed: %m"); goto child_fail; + } /* Turn directory into bind mount */ if (mount(arg_directory, arg_directory, "bind", MS_BIND, NULL) < 0) { @@ -1213,11 +1236,6 @@ int main(int argc, char *argv[]) { goto child_fail; } - if (open_terminal("dev/console", O_RDWR) != STDIN_FILENO || - dup2(STDIN_FILENO, STDOUT_FILENO) != STDOUT_FILENO || - dup2(STDIN_FILENO, STDERR_FILENO) != STDERR_FILENO) - goto child_fail; - if (mount(arg_directory, "/", "bind", MS_MOVE, NULL) < 0) { log_error("mount(MS_BIND) failed: %m"); goto child_fail; -- 2.30.2