yaffs: Handle attribute size query correctly.

If getxattr() is passed a buffer size of zero then this is a size query.
Return the size of the attribute without copying it out.

Signed-off-by: Charles Manning <cdhmanning@gmail.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/yaffs_nameval.c b/yaffs_nameval.c
index e75411b..487b03e 100644
--- a/yaffs_nameval.c
+++ b/yaffs_nameval.c
@@ -146,6 +146,12 @@ int nval_get(const char *xb, int xb_size, const YCHAR * name, char *buf,
 		pos++;
 		size--;
 
+		/* If bsize is zero then this is a size query.
+		 * Return the size, but don't copy.
+		 */
+		if (!bsize)
+			return size;
+
 		if (size <= bsize) {
 			memcpy(buf, xb + pos, size);
 			return size;