Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull overlayfs fixes from Miklos Szeredi:
"This contains a fix for a potential crash/corruption issue and another
where the suid/sgid bits weren't cleared on write"
* 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
ovl: verify upper dentry in ovl_remove_and_whiteout()
ovl: Copy up underlying inode's ->i_mode to overlay inode
ovl: handle ATTR_KILL*
diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
index c2a6b08..5c9d2d8 100644
--- a/fs/overlayfs/dir.c
+++ b/fs/overlayfs/dir.c
@@ -505,6 +505,7 @@
struct dentry *upper;
struct dentry *opaquedir = NULL;
int err;
+ int flags = 0;
if (WARN_ON(!workdir))
return -EROFS;
@@ -534,46 +535,39 @@
if (err)
goto out_dput;
+ upper = lookup_one_len(dentry->d_name.name, upperdir,
+ dentry->d_name.len);
+ err = PTR_ERR(upper);
+ if (IS_ERR(upper))
+ goto out_unlock;
+
+ err = -ESTALE;
+ if ((opaquedir && upper != opaquedir) ||
+ (!opaquedir && ovl_dentry_upper(dentry) &&
+ upper != ovl_dentry_upper(dentry))) {
+ goto out_dput_upper;
+ }
+
whiteout = ovl_whiteout(workdir, dentry);
err = PTR_ERR(whiteout);
if (IS_ERR(whiteout))
- goto out_unlock;
+ goto out_dput_upper;
- upper = ovl_dentry_upper(dentry);
- if (!upper) {
- upper = lookup_one_len(dentry->d_name.name, upperdir,
- dentry->d_name.len);
- err = PTR_ERR(upper);
- if (IS_ERR(upper))
- goto kill_whiteout;
+ if (d_is_dir(upper))
+ flags = RENAME_EXCHANGE;
- err = ovl_do_rename(wdir, whiteout, udir, upper, 0);
- dput(upper);
- if (err)
- goto kill_whiteout;
- } else {
- int flags = 0;
+ err = ovl_do_rename(wdir, whiteout, udir, upper, flags);
+ if (err)
+ goto kill_whiteout;
+ if (flags)
+ ovl_cleanup(wdir, upper);
- if (opaquedir)
- upper = opaquedir;
- err = -ESTALE;
- if (upper->d_parent != upperdir)
- goto kill_whiteout;
-
- if (is_dir)
- flags |= RENAME_EXCHANGE;
-
- err = ovl_do_rename(wdir, whiteout, udir, upper, flags);
- if (err)
- goto kill_whiteout;
-
- if (is_dir)
- ovl_cleanup(wdir, upper);
- }
ovl_dentry_version_inc(dentry->d_parent);
out_d_drop:
d_drop(dentry);
dput(whiteout);
+out_dput_upper:
+ dput(upper);
out_unlock:
unlock_rename(workdir, upperdir);
out_dput:
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index c831c2e..d1cdc60 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -80,6 +80,9 @@
goto out_drop_write;
}
+ if (attr->ia_valid & (ATTR_KILL_SUID|ATTR_KILL_SGID))
+ attr->ia_valid &= ~ATTR_MODE;
+
inode_lock(upperdentry->d_inode);
err = notify_change(upperdentry, attr, NULL);
if (!err)
@@ -410,12 +413,11 @@
if (!inode)
return NULL;
- mode &= S_IFMT;
-
inode->i_ino = get_next_ino();
inode->i_mode = mode;
inode->i_flags |= S_NOATIME | S_NOCMTIME;
+ mode &= S_IFMT;
switch (mode) {
case S_IFDIR:
inode->i_private = oe;
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index 4bd9b5b..cfbca53 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -187,6 +187,7 @@
{
to->i_uid = from->i_uid;
to->i_gid = from->i_gid;
+ to->i_mode = from->i_mode;
}
/* dir.c */
