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/9p/acl.c b/fs/9p/acl.c
index 6ff30b1..9da967f 100644
--- a/fs/9p/acl.c
+++ b/fs/9p/acl.c
@@ -220,15 +220,12 @@
struct posix_acl *acl;
int error;
- if (strcmp(name, "") != 0)
- return -EINVAL;
-
v9ses = v9fs_dentry2v9ses(dentry);
/*
* We allow set/get/list of acl when access=client is not specified
*/
if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT)
- return v9fs_xattr_get(dentry, handler->prefix, buffer, size);
+ return v9fs_xattr_get(dentry, handler->name, buffer, size);
acl = v9fs_get_cached_acl(d_inode(dentry), handler->flags);
if (IS_ERR(acl))
@@ -250,16 +247,13 @@
struct v9fs_session_info *v9ses;
struct inode *inode = d_inode(dentry);
- if (strcmp(name, "") != 0)
- return -EINVAL;
-
v9ses = v9fs_dentry2v9ses(dentry);
/*
* set the attribute on the remote. Without even looking at the
* xattr value. We leave it to the server to validate
*/
if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT)
- return v9fs_xattr_set(dentry, handler->prefix, value, size,
+ return v9fs_xattr_set(dentry, handler->name, value, size,
flags);
if (S_ISLNK(inode->i_mode))
@@ -319,7 +313,7 @@
default:
BUG();
}
- retval = v9fs_xattr_set(dentry, handler->prefix, value, size, flags);
+ retval = v9fs_xattr_set(dentry, handler->name, value, size, flags);
if (!retval)
set_cached_acl(inode, handler->flags, acl);
err_out:
@@ -328,14 +322,14 @@
}
const struct xattr_handler v9fs_xattr_acl_access_handler = {
- .prefix = XATTR_NAME_POSIX_ACL_ACCESS,
+ .name = XATTR_NAME_POSIX_ACL_ACCESS,
.flags = ACL_TYPE_ACCESS,
.get = v9fs_xattr_get_acl,
.set = v9fs_xattr_set_acl,
};
const struct xattr_handler v9fs_xattr_acl_default_handler = {
- .prefix = XATTR_NAME_POSIX_ACL_DEFAULT,
+ .name = XATTR_NAME_POSIX_ACL_DEFAULT,
.flags = ACL_TYPE_DEFAULT,
.get = v9fs_xattr_get_acl,
.set = v9fs_xattr_set_acl,