[PATCH 1/2] xfs: Fixes to "invalidate cached acl if set directly via xattr"

[Andreas Gruenbacher <agruenba@xxxxxxxxxx>]

Don't match arbitrary name prefixes like "S" when checking for the
attribute names "SGI_ACL_{FILE,DEFAULT}".

Function forget_cached_acl only exists in kernels that have POSIX ACL
support; guard calls to that function by CONFIG_XFS_POSIX_ACL.

Signed-off-by: Andreas Gruenbacher <agruenba@xxxxxxxxxx>
---
 fs/xfs/xfs_xattr.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/xfs/xfs_xattr.c b/fs/xfs/xfs_xattr.c
index 2e1eb80..1542d64 100644
--- a/fs/xfs/xfs_xattr.c
+++ b/fs/xfs/xfs_xattr.c
@@ -80,10 +80,12 @@ xfs_xattr_set(struct dentry *dentry, const char *name, 
const void *value,
         * consistent.
         */
        if (!error && (xflags & ATTR_ROOT)) {
-               if (!strncmp(name, SGI_ACL_FILE, strlen(name)))
+#ifdef CONFIG_XFS_POSIX_ACL
+               if (!strcmp(name, SGI_ACL_FILE)
                        forget_cached_acl(VFS_I(ip), ACL_TYPE_ACCESS);
-               else if (!strncmp(name, SGI_ACL_DEFAULT, strlen(name)))
+               else if (!strcmp(name, SGI_ACL_DEFAULT))
                        forget_cached_acl(VFS_I(ip), ACL_TYPE_DEFAULT);
+#endif
        }
 
        return error;
-- 
2.5.0