From 0d2edd3791bb172a59d708d5c94330bbd6050f97 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Wed, 23 Sep 2015 14:00:12 +0300 Subject: [PATCH] drm/amdgpu: integer overflow in amdgpu_info_ioctl() MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The "alloc_size" calculation can overflow leading to memory corruption. Reviewed-by: Christian König Reported-by: Ilja Van Sprundel Signed-off-by: Dan Carpenter Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c index 22367939ebf1..8c735f544b66 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c @@ -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, -- 2.34.1