diff options
Diffstat (limited to 'src/core')
| -rw-r--r-- | src/core/main.c | 21 | ||||
| -rw-r--r-- | src/core/manager.c | 40 |
2 files changed, 36 insertions, 25 deletions
diff --git a/src/core/main.c b/src/core/main.c index 6fe440277e..0fad393323 100644 --- a/src/core/main.c +++ b/src/core/main.c @@ -1532,15 +1532,8 @@ int main(int argc, char *argv[]) { * need to do that for user instances since they never log * into the console. */ log_show_color(colors_enabled()); - make_null_stdio(); - } - - /* Initialize default unit */ - r = free_and_strdup(&arg_default_unit, SPECIAL_DEFAULT_TARGET); - if (r < 0) { - log_emergency_errno(r, "Failed to set default unit %s: %m", SPECIAL_DEFAULT_TARGET); - error_message = "Failed to set default unit"; - goto finish; + if (make_null_stdio() < 0) + log_warning_errno(errno, "Failed to redirect standard streams to /dev/null: %m"); } r = initialize_join_controllers(); @@ -1590,6 +1583,16 @@ int main(int argc, char *argv[]) { goto finish; } + /* Initialize default unit */ + if (!arg_default_unit) { + r = free_and_strdup(&arg_default_unit, SPECIAL_DEFAULT_TARGET); + if (r < 0) { + log_emergency_errno(r, "Failed to set default unit %s: %m", SPECIAL_DEFAULT_TARGET); + error_message = "Failed to set default unit"; + goto finish; + } + } + if (arg_action == ACTION_TEST && geteuid() == 0) { log_error("Don't run test mode as root."); diff --git a/src/core/manager.c b/src/core/manager.c index 5253cb3712..c1dce62a18 100644 --- a/src/core/manager.c +++ b/src/core/manager.c @@ -1720,16 +1720,15 @@ static int manager_dispatch_notify_fd(sd_event_source *source, int fd, uint32_t return 0; } - n = recvmsg(m->notify_fd, &msghdr, MSG_DONTWAIT|MSG_CMSG_CLOEXEC); + n = recvmsg(m->notify_fd, &msghdr, MSG_DONTWAIT|MSG_CMSG_CLOEXEC|MSG_TRUNC); if (n < 0) { - if (!IN_SET(errno, EAGAIN, EINTR)) - log_error("Failed to receive notification message: %m"); + if (IN_SET(errno, EAGAIN, EINTR)) + return 0; /* Spurious wakeup, try again */ - /* It's not an option to return an error here since it - * would disable the notification handler entirely. Services - * wouldn't be able to send the WATCHDOG message for - * example... */ - return 0; + /* If this is any other, real error, then let's stop processing this socket. This of course means we + * won't take notification messages anymore, but that's still better than busy looping around this: + * being woken up over and over again but being unable to actually read the message off the socket. */ + return log_error_errno(errno, "Failed to receive notification message: %m"); } CMSG_FOREACH(cmsg, &msghdr) { @@ -1762,13 +1761,19 @@ static int manager_dispatch_notify_fd(sd_event_source *source, int fd, uint32_t return 0; } - if ((size_t) n >= sizeof(buf)) { + if ((size_t) n >= sizeof(buf) || (msghdr.msg_flags & MSG_TRUNC)) { log_warning("Received notify message exceeded maximum size. Ignoring."); return 0; } - /* The message should be a string. Here we make sure it's NUL-terminated, - * but only the part until first NUL will be used anyway. */ + /* As extra safety check, let's make sure the string we get doesn't contain embedded NUL bytes. We permit one + * trailing NUL byte in the message, but don't expect it. */ + if (n > 1 && memchr(buf, 0, n-1)) { + log_warning("Received notify message with embedded NUL bytes. Ignoring."); + return 0; + } + + /* Make sure it's NUL-terminated. */ buf[n] = 0; /* Notify every unit that might be interested, but try @@ -1941,14 +1946,17 @@ static int manager_dispatch_signal_fd(sd_event_source *source, int fd, uint32_t for (;;) { n = read(m->signal_fd, &sfsi, sizeof(sfsi)); if (n != sizeof(sfsi)) { + if (n >= 0) { + log_warning("Truncated read from signal fd (%zu bytes)!", n); + return 0; + } - if (n >= 0) - return -EIO; - - if (errno == EINTR || errno == EAGAIN) + if (IN_SET(errno, EINTR, EAGAIN)) break; - return -errno; + /* We return an error here, which will kill this handler, + * to avoid a busy loop on read error. */ + return log_error_errno(errno, "Reading from signal fd failed: %m"); } log_received_signal(sfsi.ssi_signo == SIGCHLD || |