summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorMiklos Szeredi <miklos@szeredi.hu>2015-12-04 19:18:48 +0100
committerAl Viro <viro@zeniv.linux.org.uk>2015-12-06 12:28:23 -0500
commitacff81ec2c79492b180fade3c2894425cd35a545 (patch)
treeda3c7514877f6881b8be76e203614917227be52a
parent31ade3b83e1821da5fbb2f11b5b3d4ab2ec39db8 (diff)
ovl: fix permission checking for setattr
[Al Viro] The bug is in being too enthusiastic about optimizing ->setattr() away - instead of "copy verbatim with metadata" + "chmod/chown/utimes" (with the former being always safe and the latter failing in case of insufficient permissions) it tries to combine these two. Note that copyup itself will have to do ->setattr() anyway; _that_ is where the elevated capabilities are right. Having these two ->setattr() (one to set verbatim copy of metadata, another to do what overlayfs ->setattr() had been asked to do in the first place) combined is where it breaks. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Cc: <stable@vger.kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
-rw-r--r--fs/overlayfs/inode.c8
1 files changed, 4 insertions, 4 deletions
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index ec0c2a050043..961284936917 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -49,13 +49,13 @@ int ovl_setattr(struct dentry *dentry, struct iattr *attr)
if (err)
goto out;
- upperdentry = ovl_dentry_upper(dentry);
- if (upperdentry) {
+ err = ovl_copy_up(dentry);
+ if (!err) {
+ upperdentry = ovl_dentry_upper(dentry);
+
mutex_lock(&upperdentry->d_inode->i_mutex);
err = notify_change(upperdentry, attr, NULL);
mutex_unlock(&upperdentry->d_inode->i_mutex);
- } else {
- err = ovl_copy_up_last(dentry, attr, false);
}
ovl_drop_write(dentry);
out: