When accessing the lower_file pointer located in private_data of
eCryptfs files, there is no need to check to see if the private_data
pointer has been initialized to a non-NULL value. The file->private_data
and file->private_data->lower_file pointers are always initialized to
non-NULL values in ecryptfs_open().
This change quiets a Smatch warning:
CHECK /var/scm/kernel/linux/fs/ecryptfs/file.c
fs/ecryptfs/file.c:321 ecryptfs_unlocked_ioctl() error: potential NULL dereference 'lower_file'.
fs/ecryptfs/file.c:335 ecryptfs_compat_ioctl() error: potential NULL dereference 'lower_file'.
Signed-off-by: Tyler Hicks <tyhicks@xxxxxxxxxxxxx>
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
Thanks, Dan! You're right that the "if (ecryptfs_file_to_private(file))" check
is not needed.
I'll include this patch in an upcoming pull request.
Tyler
fs/ecryptfs/file.c | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)
diff --git a/fs/ecryptfs/file.c b/fs/ecryptfs/file.c
index 2229a74..b1eaa7a 100644
--- a/fs/ecryptfs/file.c
+++ b/fs/ecryptfs/file.c
@@ -313,11 +313,9 @@ static int ecryptfs_fasync(int fd, struct file *file, int flag)
static long
ecryptfs_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
- struct file *lower_file = NULL;
+ struct file *lower_file = ecryptfs_file_to_lower(file);
long rc = -ENOTTY;
- if (ecryptfs_file_to_private(file))
- lower_file = ecryptfs_file_to_lower(file);
if (lower_file->f_op->unlocked_ioctl)
rc = lower_file->f_op->unlocked_ioctl(lower_file, cmd, arg);
return rc;
@@ -327,11 +325,9 @@ ecryptfs_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
static long
ecryptfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
- struct file *lower_file = NULL;
+ struct file *lower_file = ecryptfs_file_to_lower(file);
long rc = -ENOIOCTLCMD;
- if (ecryptfs_file_to_private(file))
- lower_file = ecryptfs_file_to_lower(file);
if (lower_file->f_op && lower_file->f_op->compat_ioctl)
rc = lower_file->f_op->compat_ioctl(lower_file, cmd, arg);
return rc;
--
1.8.3.2
--
To unsubscribe from this list: send the line "unsubscribe ecryptfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
