drm/amdgpu: integer overflow in amdgpu_info_ioctl()

The "alloc_size" calculation can overflow leading to memory corruption.

Reviewed-by: Christian König <christian.koenig@amd.com>
Reported-by: Ilja Van Sprundel <ivansprundel@ioactive.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
Dan Carpenter 2015-09-23 14:00:12 +03:00 committed by Alex Deucher
parent 1d263474c4
commit 0d2edd3791

View file

@ -390,7 +390,7 @@ static int amdgpu_info_ioctl(struct drm_device *dev, void *data, struct drm_file
min((size_t)size, sizeof(vram_gtt))) ? -EFAULT : 0;
}
case AMDGPU_INFO_READ_MMR_REG: {
unsigned n, alloc_size = info->read_mmr_reg.count * 4;
unsigned n, alloc_size;
uint32_t *regs;
unsigned se_num = (info->read_mmr_reg.instance >>
AMDGPU_INFO_MMR_SE_INDEX_SHIFT) &
@ -406,9 +406,10 @@ static int amdgpu_info_ioctl(struct drm_device *dev, void *data, struct drm_file
if (sh_num == AMDGPU_INFO_MMR_SH_INDEX_MASK)
sh_num = 0xffffffff;
regs = kmalloc(alloc_size, GFP_KERNEL);
regs = kmalloc_array(info->read_mmr_reg.count, sizeof(*regs), GFP_KERNEL);
if (!regs)
return -ENOMEM;
alloc_size = info->read_mmr_reg.count * sizeof(*regs);
for (i = 0; i < info->read_mmr_reg.count; i++)
if (amdgpu_asic_read_register(adev, se_num, sh_num,