vfs: Distinguish between full xattr names and proper prefixes
Add an additional "name" field to struct xattr_handler. When the name
is set, the handler matches attributes with exactly that name. When the
prefix is set instead, the handler matches attributes with the given
prefix and with a non-empty suffix.
This patch should avoid bugs like the one fixed in commit c361016a in
the future.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c
index e9164f0..5823f98 100644
--- a/fs/ocfs2/xattr.c
+++ b/fs/ocfs2/xattr.c
@@ -544,8 +544,7 @@
if (name_index > 0 && name_index < OCFS2_XATTR_MAX)
handler = ocfs2_xattr_handler_map[name_index];
-
- return handler ? handler->prefix : NULL;
+ return handler ? xattr_prefix(handler) : NULL;
}
static u32 ocfs2_xattr_name_hash(struct inode *inode,
@@ -7249,8 +7248,6 @@
struct dentry *dentry, const char *name,
void *buffer, size_t size)
{
- if (strcmp(name, "") == 0)
- return -EINVAL;
return ocfs2_xattr_get(d_inode(dentry), OCFS2_XATTR_INDEX_SECURITY,
name, buffer, size);
}
@@ -7259,9 +7256,6 @@
struct dentry *dentry, const char *name,
const void *value, size_t size, int flags)
{
- if (strcmp(name, "") == 0)
- return -EINVAL;
-
return ocfs2_xattr_set(d_inode(dentry), OCFS2_XATTR_INDEX_SECURITY,
name, value, size, flags);
}
@@ -7345,8 +7339,6 @@
struct dentry *dentry, const char *name,
void *buffer, size_t size)
{
- if (strcmp(name, "") == 0)
- return -EINVAL;
return ocfs2_xattr_get(d_inode(dentry), OCFS2_XATTR_INDEX_TRUSTED,
name, buffer, size);
}
@@ -7355,9 +7347,6 @@
struct dentry *dentry, const char *name,
const void *value, size_t size, int flags)
{
- if (strcmp(name, "") == 0)
- return -EINVAL;
-
return ocfs2_xattr_set(d_inode(dentry), OCFS2_XATTR_INDEX_TRUSTED,
name, value, size, flags);
}
@@ -7398,8 +7387,6 @@
{
struct ocfs2_super *osb = OCFS2_SB(dentry->d_sb);
- if (strcmp(name, "") == 0)
- return -EINVAL;
if (osb->s_mount_opt & OCFS2_MOUNT_NOUSERXATTR)
return -EOPNOTSUPP;
return ocfs2_xattr_get(d_inode(dentry), OCFS2_XATTR_INDEX_USER, name,
@@ -7412,8 +7399,6 @@
{
struct ocfs2_super *osb = OCFS2_SB(dentry->d_sb);
- if (strcmp(name, "") == 0)
- return -EINVAL;
if (osb->s_mount_opt & OCFS2_MOUNT_NOUSERXATTR)
return -EOPNOTSUPP;