Commit c43f7b8f authored by Tyler Hicks's avatar Tyler Hicks
Browse files

eCryptfs: Handle ioctl calls with unlocked and compat functions 

Lower filesystems that only implemented unlocked_ioctl weren't being
passed ioctl calls because eCryptfs only checked for
lower_file->f_op->ioctl and returned -ENOTTY if it was NULL.

eCryptfs shouldn't implement ioctl(), since it doesn't require the BKL.
This patch introduces ecryptfs_unlocked_ioctl() and
ecryptfs_compat_ioctl(), which passes the calls on to the lower file
system.

https://bugs.launchpad.net/ecryptfs/+bug/469664



Reported-by: default avatarJames Dupin <james.dupin@gmail.com>
Cc: stable@kernel.org
Signed-off-by: default avatarTyler Hicks <tyhicks@linux.vnet.ibm.com>
parent a1275c3b

fs/ecryptfs/file.c

+35 −21
Original line number Diff line number Diff line
@@ -292,12 +292,40 @@ static int ecryptfs_fasync(int fd, struct file *file, int flag) 
	return rc;

}



static int ecryptfs_ioctl(struct inode *inode, struct file *file,

			  unsigned int cmd, unsigned long arg);

static long

ecryptfs_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)

{

	struct file *lower_file = NULL;

	long rc = -ENOTTY;



	if (ecryptfs_file_to_private(file))

		lower_file = ecryptfs_file_to_lower(file);

	if (lower_file && lower_file->f_op && lower_file->f_op->unlocked_ioctl)

		rc = lower_file->f_op->unlocked_ioctl(lower_file, cmd, arg);

	return rc;

}



#ifdef CONFIG_COMPAT

static long

ecryptfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)

{

	struct file *lower_file = NULL;

	long rc = -ENOIOCTLCMD;



	if (ecryptfs_file_to_private(file))

		lower_file = ecryptfs_file_to_lower(file);

	if (lower_file && lower_file->f_op && lower_file->f_op->compat_ioctl)

		rc = lower_file->f_op->compat_ioctl(lower_file, cmd, arg);

	return rc;

}

#endif



const struct file_operations ecryptfs_dir_fops = {

	.readdir = ecryptfs_readdir,

	.ioctl = ecryptfs_ioctl,

	.unlocked_ioctl = ecryptfs_unlocked_ioctl,

#ifdef CONFIG_COMPAT

	.compat_ioctl = ecryptfs_compat_ioctl,

#endif

	.open = ecryptfs_open,

	.flush = ecryptfs_flush,

	.release = ecryptfs_release,
@@ -313,7 +341,10 @@ const struct file_operations ecryptfs_main_fops = { 
	.write = do_sync_write,

	.aio_write = generic_file_aio_write,

	.readdir = ecryptfs_readdir,

	.ioctl = ecryptfs_ioctl,

	.unlocked_ioctl = ecryptfs_unlocked_ioctl,

#ifdef CONFIG_COMPAT

	.compat_ioctl = ecryptfs_compat_ioctl,

#endif

	.mmap = generic_file_mmap,

	.open = ecryptfs_open,

	.flush = ecryptfs_flush,
@@ -322,20 +353,3 @@ const struct file_operations ecryptfs_main_fops = { 
	.fasync = ecryptfs_fasync,

	.splice_read = generic_file_splice_read,

};
 


static int

ecryptfs_ioctl(struct inode *inode, struct file *file, unsigned int cmd,

	       unsigned long arg)

{

	int rc = 0;

	struct file *lower_file = NULL;



	if (ecryptfs_file_to_private(file))

		lower_file = ecryptfs_file_to_lower(file);

	if (lower_file && lower_file->f_op && lower_file->f_op->ioctl)

		rc = lower_file->f_op->ioctl(ecryptfs_inode_to_lower(inode),

					     lower_file, cmd, arg);

	else

		rc = -ENOTTY;

	return rc;

}

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