util: storage: Fix parsing of 'exportname' from legacy NBD strings

If the nbd export name contains a colon, our parser would not parse it
properly as we split the string by colons. Modify the code to look up
the exportname and copy any trailing characters as the export name is
supposed to be at the end of the string.

https://bugzilla.redhat.com/show_bug.cgi?id=1733044Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJiri Denemark <jdenemar@redhat.com>

src/util/virstoragefile.c

@@ -2928,6 +2928,7 @@ virStorageSourceParseNBDColonString(const char *nbdstr,
                                     virStorageSourcePtr src)
 {
     VIR_AUTOSTRINGLIST backing = NULL;
+    const char *exportname;
 
     if (!(backing = virStringSplit(nbdstr, ":", 0)))
         return -1;
@@ -2975,8 +2976,9 @@ virStorageSourceParseNBDColonString(const char *nbdstr,
             return -1;
     }
 
-    if (backing[3] && STRPREFIX(backing[3], "exportname=")) {
-        if (VIR_STRDUP(src->path, backing[3] + strlen("exportname=")) < 0)
+    if ((exportname = strstr(nbdstr, "exportname="))) {
+        exportname += strlen("exportname=");
+        if (VIR_STRDUP(src->path, exportname) < 0)
             return -1;
     }
 

tests/virstoragetest.c

@@ -1262,6 +1262,14 @@ mymain(void)
                        "<source protocol='nbd' name='blah'>\n"
                        "  <host name='example.org' port='6000'/>\n"
                        "</source>\n");
+    TEST_BACKING_PARSE("nbd:example.org:6000:exportname=:",
+                       "<source protocol='nbd' name=':'>\n"
+                       "  <host name='example.org' port='6000'/>\n"
+                       "</source>\n");
+    TEST_BACKING_PARSE("nbd:example.org:6000:exportname=:test",
+                       "<source protocol='nbd' name=':test'>\n"
+                       "  <host name='example.org' port='6000'/>\n"
+                       "</source>\n");
     TEST_BACKING_PARSE("nbd://example.org:1234",
                        "<source protocol='nbd'>\n"
                        "  <host name='example.org' port='1234'/>\n"