Re: systemd CVE-2016-7796

[Brian May <bam@debian.org>]

Here is a new revised patch:

-- 
--- systemd-44.orig/src/manager.c
+++ systemd-44/src/manager.c
@@ -2029,14 +2029,17 @@
                 msghdr.msg_control = &control;
                 msghdr.msg_controllen = sizeof(control);
 
-                if ((n = recvmsg(m->notify_watch.fd, &msghdr, MSG_DONTWAIT)) <= 0) {
-                        if (n >= 0)
-                                return -EIO;
-
-                        if (errno == EAGAIN || errno == EINTR)
+                if ((n = recvmsg(m->notify_watch.fd, &msghdr, MSG_DONTWAIT)) < 0) {
+                        if (errno == EAGAIN || errno == EINTR) {
+                                log_error("Failed to receive notification message: %m");
                                 break;
+                        }
 
-                        return -errno;
+                        /* 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 (msghdr.msg_controllen < CMSG_LEN(sizeof(struct ucred)) ||
@@ -2058,7 +2061,7 @@
                 assert((size_t) n < sizeof(buf));
                 buf[n] = 0;
                 if (!(tags = strv_split(buf, "\n\r")))
-                        return -ENOMEM;
+                        return 0;
 
                 log_debug("Got notification message for unit %s", u->id);
 
Brian May <bam@debian.org>