From: Peilin Ye Date: Tue, 28 Jul 2020 19:29:24 +0000 (-0400) Subject: drm/amdgpu: Prevent kernel-infoleak in amdgpu_info_ioctl() X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=543e8669ed9bfb30545fd52bc0e047ca4df7fb31;p=linux.git drm/amdgpu: Prevent kernel-infoleak in amdgpu_info_ioctl() Compiler leaves a 4-byte hole near the end of `dev_info`, causing amdgpu_info_ioctl() to copy uninitialized kernel stack memory to userspace when `size` is greater than 356. In 2015 we tried to fix this issue by doing `= {};` on `dev_info`, which unfortunately does not initialize that 4-byte hole. Fix it by using memset() instead. Cc: stable@vger.kernel.org Fixes: c193fa91b918 ("drm/amdgpu: information leak in amdgpu_info_ioctl()") Fixes: d38ceaf99ed0 ("drm/amdgpu: add core driver (v4)") Suggested-by: Dan Carpenter Reviewed-by: Christian König Signed-off-by: Peilin Ye Signed-off-by: Alex Deucher --- diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c index d7e17e34fee17..21292098bc023 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c @@ -692,9 +692,10 @@ static int amdgpu_info_ioctl(struct drm_device *dev, void *data, struct drm_file return n ? -EFAULT : 0; } case AMDGPU_INFO_DEV_INFO: { - struct drm_amdgpu_info_device dev_info = {}; + struct drm_amdgpu_info_device dev_info; uint64_t vm_size; + memset(&dev_info, 0, sizeof(dev_info)); dev_info.device_id = dev->pdev->device; dev_info.chip_rev = adev->rev_id; dev_info.external_rev = adev->external_rev_id;