eCryptfs: file->private_data is always valid (2000f5be) · Commits · 戴 / test

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@canonical.com> Reported-by:

Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by:

Geyslan G. Bem <geyslan@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk>

fs/ecryptfs/file.c

+2 −6

Original line number	Diff line number	Diff line
		@@ -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;

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