sd-bus: don't choke if somebody sends us a message with a unix fd count of 0

It's kinda pointless to include a unix fd header field in messages if it
carries the value 0, but let's do this anyway...

diff --git a/src/libsystemd/sd-bus/bus-message.c b/src/libsystemd/sd-bus/bus-message.c
index 97ab0e3beac81798d1e0f13aabf683b9c3d5a415..b9d7f6dbfd2961fd1e83548b74d1717581413c85 100644 (file)
--- a/src/libsystemd/sd-bus/bus-message.c
+++ b/src/libsystemd/sd-bus/bus-message.c
@@ -4885,6 +4885,7 @@ int bus_message_parse_fields(sd_bus_message *m) {
         size_t ri;
         int r;
         uint32_t unix_fds = 0;
         size_t ri;
         int r;
         uint32_t unix_fds = 0;

+        bool unix_fds_set = false;

         void *offsets = NULL;
         unsigned n_offsets = 0;
         size_t sz = 0;
         void *offsets = NULL;
         unsigned n_offsets = 0;
         size_t sz = 0;


@@ -5097,7 +5098,7 @@ int bus_message_parse_fields(sd_bus_message *m) {
                 }
 
                 case BUS_MESSAGE_HEADER_UNIX_FDS:
                 }
 
                 case BUS_MESSAGE_HEADER_UNIX_FDS:

-                        if (unix_fds != 0)
+                        if (unix_fds_set)

                                 return -EBADMSG;
 
                         if (!streq(signature, "u"))
                                 return -EBADMSG;
 
                         if (!streq(signature, "u"))


@@ -5107,9 +5108,7 @@ int bus_message_parse_fields(sd_bus_message *m) {
                         if (r < 0)
                                 return -EBADMSG;
 
                         if (r < 0)
                                 return -EBADMSG;
 

-                        if (unix_fds == 0)
-                                return -EBADMSG;
-
+                        unix_fds_set = true;

                         break;
 
                 default:
                         break;
 
                 default: