From 413d5a9edbb45eec4dbb1904fe689b561ea5d143 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Fri, 7 Apr 2017 10:58:40 -0700 Subject: [PATCH] ubifs: check for consistent encryption contexts in ubifs_lookup() As ext4 and f2fs do, ubifs should check for consistent encryption contexts during ->lookup() in an encrypted directory. This protects certain users of filesystem encryption against certain types of offline attacks. Signed-off-by: Eric Biggers Signed-off-by: Theodore Ts'o --- fs/ubifs/dir.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c index 30825d882aa9..bbe2b346a94f 100644 --- a/fs/ubifs/dir.c +++ b/fs/ubifs/dir.c @@ -285,6 +285,15 @@ static struct dentry *ubifs_lookup(struct inode *dir, struct dentry *dentry, goto out_dent; } + if (ubifs_crypt_is_encrypted(dir) && + (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) && + !fscrypt_has_permitted_context(dir, inode)) { + ubifs_warn(c, "Inconsistent encryption contexts: %lu/%lu", + dir->i_ino, inode->i_ino); + err = -EPERM; + goto out_inode; + } + done: kfree(dent); fscrypt_free_filename(&nm); @@ -295,6 +304,8 @@ done: d_add(dentry, inode); return NULL; +out_inode: + iput(inode); out_dent: kfree(dent); out_fname: -- 2.20.1