From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kees Cook Subject: [PATCH] drm/i915: Use copy_from_user() in fence copying Date: Wed, 6 Dec 2017 12:28:50 -0800 Message-ID: <20171206202850.GA38365@beast> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Content-Disposition: inline List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Jason Ekstrand Cc: intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org List-Id: dri-devel@lists.freedesktop.org VGhlcmUncyBubyBnb29kIHJlYXNvbiB0byBzZXBhcmF0ZSB0aGUgYWNjZXNzX29rKCkgZnJvbSB0 aGUgY29weSwKZXNwZWNpYWxseSBzaW5jZSB0aGUgYWNjZXNzX29rKCkgc2l6ZSBpcyBoYXJkLWNv ZGVkIGluc3RlYWQgb2YgdXNpbmcKc2l6ZW9mKCkuIEluc3RlYWQsIGp1c3QgdXNlIGNvcHlfZnJv bV91c2VyKCkgZGlyZWN0bHkuCgpGaXhlczogY2Y2ZTdiYWM2MzU3ICgiZHJtL2k5MTU6IEFkZCBz dXBwb3J0IGZvciBkcm0gc3luY29ianMiKQpDYzogSmFzb24gRWtzdHJhbmQgPGphc29uQGpsZWtz dHJhbmQubmV0PgpDYzogQ2hyaXMgV2lsc29uIDxjaHJpc0BjaHJpcy13aWxzb24uY28udWs+ClNp Z25lZC1vZmYtYnk6IEtlZXMgQ29vayA8a2Vlc2Nvb2tAY2hyb21pdW0ub3JnPgotLS0KIGRyaXZl cnMvZ3B1L2RybS9pOTE1L2k5MTVfZ2VtX2V4ZWNidWZmZXIuYyB8IDQgKy0tLQogMSBmaWxlIGNo YW5nZWQsIDEgaW5zZXJ0aW9uKCspLCAzIGRlbGV0aW9ucygtKQoKZGlmZiAtLWdpdCBhL2RyaXZl cnMvZ3B1L2RybS9pOTE1L2k5MTVfZ2VtX2V4ZWNidWZmZXIuYyBiL2RyaXZlcnMvZ3B1L2RybS9p OTE1L2k5MTVfZ2VtX2V4ZWNidWZmZXIuYwppbmRleCA0MzVlZDk1ZGYxNDQuLjFkYTcwMzIxM2Ix NyAxMDA2NDQKLS0tIGEvZHJpdmVycy9ncHUvZHJtL2k5MTUvaTkxNV9nZW1fZXhlY2J1ZmZlci5j CisrKyBiL2RyaXZlcnMvZ3B1L2RybS9pOTE1L2k5MTVfZ2VtX2V4ZWNidWZmZXIuYwpAQCAtMjA4 Nyw4ICsyMDg3LDYgQEAgZ2V0X2ZlbmNlX2FycmF5KHN0cnVjdCBkcm1faTkxNV9nZW1fZXhlY2J1 ZmZlcjIgKmFyZ3MsCiAJCXJldHVybiBFUlJfUFRSKC1FSU5WQUwpOwogCiAJdXNlciA9IHU2NF90 b191c2VyX3B0cihhcmdzLT5jbGlwcmVjdHNfcHRyKTsKLQlpZiAoIWFjY2Vzc19vayhWRVJJRllf UkVBRCwgdXNlciwgbmZlbmNlcyAqIDIgKiBzaXplb2YodTMyKSkpCi0JCXJldHVybiBFUlJfUFRS KC1FRkFVTFQpOwogCiAJZmVuY2VzID0ga3ZtYWxsb2NfYXJyYXkoYXJncy0+bnVtX2NsaXByZWN0 cywgc2l6ZW9mKCpmZW5jZXMpLAogCQkJCV9fR0ZQX05PV0FSTiB8IEdGUF9LRVJORUwpOwpAQCAt MjA5OSw3ICsyMDk3LDcgQEAgZ2V0X2ZlbmNlX2FycmF5KHN0cnVjdCBkcm1faTkxNV9nZW1fZXhl Y2J1ZmZlcjIgKmFyZ3MsCiAJCXN0cnVjdCBkcm1faTkxNV9nZW1fZXhlY19mZW5jZSBmZW5jZTsK IAkJc3RydWN0IGRybV9zeW5jb2JqICpzeW5jb2JqOwogCi0JCWlmIChfX2NvcHlfZnJvbV91c2Vy KCZmZW5jZSwgdXNlcisrLCBzaXplb2YoZmVuY2UpKSkgeworCQlpZiAoY29weV9mcm9tX3VzZXIo JmZlbmNlLCB1c2VyKyssIHNpemVvZihmZW5jZSkpKSB7CiAJCQllcnIgPSAtRUZBVUxUOwogCQkJ Z290byBlcnI7CiAJCX0KLS0gCjIuNy40CgoKLS0gCktlZXMgQ29vawpQaXhlbCBTZWN1cml0eQpf X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fXwpJbnRlbC1nZngg bWFpbGluZyBsaXN0CkludGVsLWdmeEBsaXN0cy5mcmVlZGVza3RvcC5vcmcKaHR0cHM6Ly9saXN0 cy5mcmVlZGVza3RvcC5vcmcvbWFpbG1hbi9saXN0aW5mby9pbnRlbC1nZngK From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752302AbdLFU26 (ORCPT ); Wed, 6 Dec 2017 15:28:58 -0500 Received: from mail-pf0-f193.google.com ([209.85.192.193]:42975 "EHLO mail-pf0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751847AbdLFU2y (ORCPT ); Wed, 6 Dec 2017 15:28:54 -0500 X-Google-Smtp-Source: AGs4zMY6wt96o1c1UW0aTR/sbkzZ+DWpeSypZzgJqTL1tSY5FcrCqa+M6HAq+9M8G0piAZ5dnQeFvA== Date: Wed, 6 Dec 2017 12:28:50 -0800 From: Kees Cook To: Jason Ekstrand Cc: Chris Wilson , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: [PATCH] drm/i915: Use copy_from_user() in fence copying Message-ID: <20171206202850.GA38365@beast> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There's no good reason to separate the access_ok() from the copy, especially since the access_ok() size is hard-coded instead of using sizeof(). Instead, just use copy_from_user() directly. Fixes: cf6e7bac6357 ("drm/i915: Add support for drm syncobjs") Cc: Jason Ekstrand Cc: Chris Wilson Signed-off-by: Kees Cook --- drivers/gpu/drm/i915/i915_gem_execbuffer.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c index 435ed95df144..1da703213b17 100644 --- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c @@ -2087,8 +2087,6 @@ get_fence_array(struct drm_i915_gem_execbuffer2 *args, return ERR_PTR(-EINVAL); user = u64_to_user_ptr(args->cliprects_ptr); - if (!access_ok(VERIFY_READ, user, nfences * 2 * sizeof(u32))) - return ERR_PTR(-EFAULT); fences = kvmalloc_array(args->num_cliprects, sizeof(*fences), __GFP_NOWARN | GFP_KERNEL); @@ -2099,7 +2097,7 @@ get_fence_array(struct drm_i915_gem_execbuffer2 *args, struct drm_i915_gem_exec_fence fence; struct drm_syncobj *syncobj; - if (__copy_from_user(&fence, user++, sizeof(fence))) { + if (copy_from_user(&fence, user++, sizeof(fence))) { err = -EFAULT; goto err; } -- 2.7.4 -- Kees Cook Pixel Security