[PATCH] xattr: listxattr fix

Patch from Andreas Gruenbacher <agruen@suse.de>

This patch fixes a bug in the ext2 and ext3 listxattr operation: Even if
an attribute is hidden from the user, the terminating NULL character was
included in the listxattr result. After the patch this doesn't happen
anymore.

fs/ext2/acl.c

@@ -421,26 +421,26 @@ static size_t
 ext2_xattr_list_acl_access(char *list, struct inode *inode,
 			   const char *name, int name_len)
 {
-	const size_t len = sizeof(XATTR_NAME_ACL_ACCESS)-1;
+	const size_t size = sizeof(XATTR_NAME_ACL_ACCESS);
 
 	if (!test_opt(inode->i_sb, POSIX_ACL))
 		return 0;
 	if (list)
-		memcpy(list, XATTR_NAME_ACL_ACCESS, len);
-	return len;
+		memcpy(list, XATTR_NAME_ACL_ACCESS, size);
+	return size;
 }
 
 static size_t
 ext2_xattr_list_acl_default(char *list, struct inode *inode,
 			    const char *name, int name_len)
 {
-	const size_t len = sizeof(XATTR_NAME_ACL_DEFAULT)-1;
+	const size_t size = sizeof(XATTR_NAME_ACL_DEFAULT);
 
 	if (!test_opt(inode->i_sb, POSIX_ACL))
 		return 0;
 	if (list)
-		memcpy(list, XATTR_NAME_ACL_DEFAULT, len);
-	return len;
+		memcpy(list, XATTR_NAME_ACL_DEFAULT, size);
+	return size;
 }
 
 static int

fs/ext2/xattr.c

@@ -409,10 +409,9 @@ bad_block:	ext2_error(inode->i_sb, "ext2_xattr_list",
 			goto bad_block;
 
 		handler = ext2_xattr_handler(entry->e_name_index);
-		if (handler) {
+		if (handler)
 			size += handler->list(NULL, inode, entry->e_name,
-					      entry->e_name_len) + 1;
-		}
+					      entry->e_name_len);
 	}
 
 	if (ext2_xattr_cache_insert(bh))
@@ -433,11 +432,9 @@ bad_block:	ext2_error(inode->i_sb, "ext2_xattr_list",
 		struct ext2_xattr_handler *handler;
 		
 		handler = ext2_xattr_handler(entry->e_name_index);
-		if (handler) {
+		if (handler)
 			buf += handler->list(buf, inode, entry->e_name,
 					     entry->e_name_len);
-			*buf++ = '\0';
-		}
 	}
 	error = size;
 

fs/ext2/xattr_user.c

@@ -29,8 +29,9 @@ ext2_xattr_user_list(char *list, struct inode *inode,
 	if (list) {
 		memcpy(list, XATTR_USER_PREFIX, prefix_len);
 		memcpy(list+prefix_len, name, name_len);
+		list[prefix_len + name_len] = '\0';
 	}
-	return prefix_len + name_len;
+	return prefix_len + name_len + 1;
 }
 
 static int

fs/ext3/acl.c

@@ -433,26 +433,26 @@ static size_t
 ext3_xattr_list_acl_access(char *list, struct inode *inode,
 			   const char *name, int name_len)
 {
-	const size_t len = sizeof(XATTR_NAME_ACL_ACCESS)-1;
+	const size_t size = sizeof(XATTR_NAME_ACL_ACCESS);
 
 	if (!test_opt(inode->i_sb, POSIX_ACL))
 		return 0;
 	if (list)
-		memcpy(list, XATTR_NAME_ACL_ACCESS, len);
-	return len;
+		memcpy(list, XATTR_NAME_ACL_ACCESS, size);
+	return size;
 }
 
 static size_t
 ext3_xattr_list_acl_default(char *list, struct inode *inode,
 			    const char *name, int name_len)
 {
-	const size_t len = sizeof(XATTR_NAME_ACL_DEFAULT)-1;
+	const size_t size = sizeof(XATTR_NAME_ACL_DEFAULT);
 
 	if (!test_opt(inode->i_sb, POSIX_ACL))
 		return 0;
 	if (list)
-		memcpy(list, XATTR_NAME_ACL_DEFAULT, len);
-	return len;
+		memcpy(list, XATTR_NAME_ACL_DEFAULT, size);
+	return size;
 }
 
 static int

fs/ext3/xattr.c

@@ -402,10 +402,9 @@ bad_block:	ext3_error(inode->i_sb, "ext3_xattr_list",
 			goto bad_block;
 
 		handler = ext3_xattr_handler(entry->e_name_index);
-		if (handler) {
+		if (handler)
 			size += handler->list(NULL, inode, entry->e_name,
-					      entry->e_name_len) + 1;
-		}
+					      entry->e_name_len);
 	}
 
 	if (ext3_xattr_cache_insert(bh))
@@ -426,11 +425,9 @@ bad_block:	ext3_error(inode->i_sb, "ext3_xattr_list",
 		struct ext3_xattr_handler *handler;
 
 		handler = ext3_xattr_handler(entry->e_name_index);
-		if (handler) {
+		if (handler)
 			buf += handler->list(buf, inode, entry->e_name,
 					     entry->e_name_len);
-			*buf++ = '\0';
-		}
 	}
 	error = size;
 

fs/ext3/xattr_user.c

@@ -31,8 +31,9 @@ ext3_xattr_user_list(char *list, struct inode *inode,
 	if (list) {
 		memcpy(list, XATTR_USER_PREFIX, prefix_len);
 		memcpy(list+prefix_len, name, name_len);
+		list[prefix_len + name_len] = '\0';
 	}
-	return prefix_len + name_len;
+	return prefix_len + name_len + 1;
 }
 
 static int