metaentry.c: Fix meta entry handling in case of xattr errors.

getxattr() call can fail in mentry_create(), so NULL-initialize
mentry->xattr_values[i] and update mentry->xattrs upon error, so there
is no attempt in mentry_free() to free unitialized xattr_names[i] and
xattr_values[i] pointers.

Fixes #38.

2 files changed, 7 insertions, 0 deletions

diff --git a/NEWS b/NEWS
index 7cf7a77..96d7b49 100644
--- a/NEWS
+++ b/NEWS
@@ -4,6 +4,9 @@ Latest stuff                          (planned release date: 2015-09-??)
  * BUGFIX: Applying metadata with extended attribute having null byte
            in value zeroed all following bytes of this xattr value.
 
+ * BUGFIX: Reading extended attributes while not having permissions
+           resulted in crash.
+
  * Empty directories not present in metadata can be now removed when
    applying stored metadata if -E / --remove-empty-dirs option is used.
 
diff --git a/src/metaentry.c b/src/metaentry.c
index fdb7f71..25bb00f 100644
--- a/src/metaentry.c
+++ b/src/metaentry.c
@@ -266,11 +266,14 @@ mentry_create(const char *path)
 			continue;
 
 		mentry->xattr_names[i] = xstrdup(attr);
+		mentry->xattr_values[i] = NULL;
+
 		vsize = getxattr(path, attr, NULL, 0);
 		if (vsize < 0) {
 			msg(MSG_ERROR, "getxattr failed for %s: %s\n",
 			    path, strerror(errno));
 			free(list);
+			mentry->xattrs = i + 1;
 			mentry_free(mentry);
 			return NULL;
 		}
@@ -283,6 +286,7 @@ mentry_create(const char *path)
 			msg(MSG_ERROR, "getxattr failed for %s: %s\n",
 			    path, strerror(errno));
 			free(list);
+			mentry->xattrs = i + 1;
 			mentry_free(mentry);
 			return NULL;
 		}