eCryptfs: ecryptfs_setattr() bugfix
There is another bug recently introduced into the ecryptfs_setattr()
function in 2.6.22. eCryptfs will attempt to treat special files like
regular eCryptfs files on chmod, chown, and so forth. This leads to a NULL
pointer dereference. This patch validates that the file is a regular file
before proceeding with operations related to the inode's crypt_stat.
Thanks to Ryusuke Konishi for finding this bug and suggesting the fix.
Signed-off-by: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index e77a2ec..0a50942 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -902,8 +902,9 @@
mutex_lock(&crypt_stat->cs_mutex);
if (S_ISDIR(dentry->d_inode->i_mode))
crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
- else if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)
- || !(crypt_stat->flags & ECRYPTFS_KEY_VALID)) {
+ else if (S_ISREG(dentry->d_inode->i_mode)
+ && (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)
+ || !(crypt_stat->flags & ECRYPTFS_KEY_VALID))) {
struct vfsmount *lower_mnt;
struct file *lower_file = NULL;
struct ecryptfs_mount_crypt_stat *mount_crypt_stat;