[ Upstream commit 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.

Cc: stable@vger.kernel.org Signed-off-by: Mikulas Patocka mpatocka@redhat.com Signed-off-by: Mike Snitzer snitzer@kernel.org Signed-off-by: He Gao hegao@google.com --- 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(-)

diff --git a/drivers/md/dm-core.h b/drivers/md/dm-core.h index 3db92d9a030b..ff73b2c17be5 100644 --- a/drivers/md/dm-core.h +++ b/drivers/md/dm-core.h @@ -19,6 +19,8 @@ #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; diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c index 5f9b9178c647..4184c8a2d497 100644 --- a/drivers/md/dm-ioctl.c +++ b/drivers/md/dm-ioctl.c @@ -1760,7 +1760,8 @@ static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl *param_kern 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; diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index 5c590895c14c..31bcdcd93c7a 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -144,7 +144,12 @@ static int alloc_targets(struct dm_table *t, unsigned int num) 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; @@ -158,7 +163,7 @@ int dm_table_create(struct dm_table **result, fmode_t mode,

if (!num_targets) { kfree(t); - return -ENOMEM; + return -EOVERFLOW; }

if (alloc_targets(t, num_targets)) {