Commit a5b1dd11 authored by Mikulas Patocka's avatar Mikulas Patocka Committed by Li Lingfeng
Browse files

dm: limit the number of targets and parameter size area 

mainline inclusion
from mainline-v6.8-rc3
commit bd504bcfec41a503b32054da5472904b404341a4
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I8YCAG
CVE: CVE-2024-23851

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=bd504bcfec41a503b32054da5472904b404341a4



--------------------------------

The kvmalloc function fails with a warning if the size is larger than
INT_MAX. The warning was triggered by a syscall testing robot.

In order to avoid the warning, this commit limits the number of targets to
1048576 and the size of the parameter area to 1073741824.

Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
Signed-off-by: default avatarMike Snitzer <snitzer@kernel.org>
Signed-off-by: default avatarLi Lingfeng <lilingfeng3@huawei.com>
parent 97ba28f6

drivers/md/dm-core.h

+2 −0
Original line number Diff line number Diff line
@@ -22,6 +22,8 @@ 
#include "dm-ima.h"



#define DM_RESERVED_MAX_IOS		1024

#define DM_MAX_TARGETS			1048576

#define DM_MAX_TARGET_PARAMS		1024



struct dm_io;

drivers/md/dm-ioctl.c

+2 −1
Original line number Diff line number Diff line
@@ -1952,7 +1952,8 @@ static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl *param_kern 
			   minimum_data_size - sizeof(param_kernel->version)))

		return -EFAULT;



	if (param_kernel->data_size < minimum_data_size) {

	if (unlikely(param_kernel->data_size < minimum_data_size) ||

	    unlikely(param_kernel->data_size > DM_MAX_TARGETS * DM_MAX_TARGET_PARAMS)) {

		DMERR("Invalid data size in the ioctl structure: %u",

		      param_kernel->data_size);

		return -EINVAL;

drivers/md/dm-table.c

+7 −2
Original line number Diff line number Diff line
@@ -129,7 +129,12 @@ static int alloc_targets(struct dm_table *t, unsigned int num) 
int dm_table_create(struct dm_table **result, blk_mode_t mode,

		    unsigned int num_targets, struct mapped_device *md)

{

	struct dm_table *t = kzalloc(sizeof(*t), GFP_KERNEL);

	struct dm_table *t;



	if (num_targets > DM_MAX_TARGETS)

		return -EOVERFLOW;



	t = kzalloc(sizeof(*t), GFP_KERNEL);



	if (!t)

		return -ENOMEM;
@@ -144,7 +149,7 @@ int dm_table_create(struct dm_table **result, blk_mode_t mode, 


	if (!num_targets) {

		kfree(t);

		return -ENOMEM;

		return -EOVERFLOW;

	}



	if (alloc_targets(t, num_targets)) {