5.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Mikulas Patocka <mpatocka@xxxxxxxxxx>
commit bd504bcfec41a503b32054da5472904b404341a4 upstream.
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: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
[srish: Apply to stable branch linux-5.4.y]
Signed-off-by: Srish Srinivasan <srish.srinivasan@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/md/dm-core.h | 2 ++
drivers/md/dm-ioctl.c | 3 ++-
drivers/md/dm-table.c | 9 +++++++--
3 files changed, 11 insertions(+), 3 deletions(-)
--- a/drivers/md/dm-core.h
+++ b/drivers/md/dm-core.h
@@ -18,6 +18,8 @@
#include "dm.h"
#define DM_RESERVED_MAX_IOS 1024
+#define DM_MAX_TARGETS 1048576
+#define DM_MAX_TARGET_PARAMS 1024
struct dm_kobject_holder {
struct kobject kobj;
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -1760,7 +1760,8 @@ static int copy_params(struct dm_ioctl _
if (copy_from_user(param_kernel, user, minimum_data_size))
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))
return -EINVAL;
secure_data = param_kernel->flags & DM_SECURE_DATA_FLAG;
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -184,7 +184,12 @@ static int alloc_targets(struct dm_table
int dm_table_create(struct dm_table **result, fmode_t mode,
unsigned 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;
@@ -199,7 +204,7 @@ int dm_table_create(struct dm_table **re
if (!num_targets) {
kfree(t);
- return -ENOMEM;
+ return -EOVERFLOW;
}
if (alloc_targets(t, num_targets)) {
