Commit 8b9bf58b authored by Thorsten Blum's avatar Thorsten Blum Committed by Tyler Hicks
Browse files

ecryptfs: Use struct_size to improve process_response + send_miscdev 



Use struct_size(), which provides additional compile-time checks for
structures with flexible array members (e.g., __must_be_array()), to
determine the allocation size for a new 'struct ecryptfs_message'.

In send_miscdev(), reuse 'msg_size' instead of recalculating it.

Signed-off-by: default avatarThorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: default avatarTyler Hicks <code@tyhicks.com>
parent f7a1c028

fs/ecryptfs/messaging.c

+2 −1
Original line number Diff line number Diff line
@@ -6,6 +6,7 @@ 
 *   Author(s): Michael A. Halcrow <mhalcrow@us.ibm.com>

 *		Tyler Hicks <code@tyhicks.com>

 */

#include <linux/overflow.h>

#include <linux/sched.h>

#include <linux/slab.h>

#include <linux/user_namespace.h>
@@ -232,7 +233,7 @@ int ecryptfs_process_response(struct ecryptfs_daemon *daemon, 
		       msg_ctx->counter, seq);

		goto unlock;

	}

	msg_size = (sizeof(*msg) + msg->data_len);

	msg_size = struct_size(msg, data, msg->data_len);

	msg_ctx->msg = kmemdup(msg, msg_size, GFP_KERNEL);

	if (!msg_ctx->msg) {

		rc = -ENOMEM;

fs/ecryptfs/miscdev.c

+5 −2
Original line number Diff line number Diff line
@@ -10,6 +10,7 @@ 
#include <linux/hash.h>

#include <linux/random.h>

#include <linux/miscdevice.h>

#include <linux/overflow.h>

#include <linux/poll.h>

#include <linux/slab.h>

#include <linux/wait.h>
@@ -148,8 +149,10 @@ int ecryptfs_send_miscdev(char *data, size_t data_size, 
			  u16 msg_flags, struct ecryptfs_daemon *daemon)

{

	struct ecryptfs_message *msg;

	size_t msg_size;



	msg = kmalloc((sizeof(*msg) + data_size), GFP_KERNEL);

	msg_size = struct_size(msg, data, data_size);

	msg = kmalloc(msg_size, GFP_KERNEL);

	if (!msg)

		return -ENOMEM;
@@ -159,7 +162,7 @@ int ecryptfs_send_miscdev(char *data, size_t data_size, 
	msg_ctx->msg->data_len = data_size;

	msg_ctx->type = msg_type;

	memcpy(msg_ctx->msg->data, data, data_size);

	msg_ctx->msg_size = (sizeof(*msg_ctx->msg) + data_size);

	msg_ctx->msg_size = msg_size;

	list_add_tail(&msg_ctx->daemon_out_list, &daemon->msg_ctx_out_queue);

	mutex_unlock(&msg_ctx->mux);