ovl: perform vfs_getxattr() with mounter creds

[ Upstream commit 554677b97257b0b69378bd74e521edb7e94769ff ]

The vfs_getxattr() in ovl_xattr_set() is used to check whether an xattr
exist on a lower layer file that is to be removed.  If the xattr does not
exist, then no need to copy up the file.

This call of vfs_getxattr() wasn't wrapped in credential override, and this
is probably okay.  But for consitency wrap this instance as well.

Reported-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Miklos Szeredi 2021-01-28 10:22:48 +01:00 committed by Greg Kroah-Hartman
parent f66fa5ec47
commit cbb9404a50

View File

@ -346,7 +346,9 @@ int ovl_xattr_set(struct dentry *dentry, struct inode *inode, const char *name,
goto out;
if (!value && !upperdentry) {
old_cred = ovl_override_creds(dentry->d_sb);
err = vfs_getxattr(realdentry, name, NULL, 0);
revert_creds(old_cred);
if (err < 0)
goto out_drop_write;
}