From patchwork Tue Nov 21 10:40:20 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Marc-Andr=C3=A9_Lureau?= X-Patchwork-Id: 13462804 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 57C22C54FB9 for ; Tue, 21 Nov 2023 10:41:41 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1r5OBU-0007eZ-F2; Tue, 21 Nov 2023 05:40:48 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1r5OBS-0007eG-Uf for qemu-devel@nongnu.org; Tue, 21 Nov 2023 05:40:46 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1r5OBR-0003Gl-E1 for qemu-devel@nongnu.org; Tue, 21 Nov 2023 05:40:46 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1700563244; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=xcSybLVQML97R4ifQxa3cpKai5dO7+D+ef9nCuYM/6s=; b=V4oTs7JhT7g78LtcGZZRGsjkPt6BcQyKhfUCXcVnwlevZEQoXUgAp8B9ypE9IRi30CPGcb qF3gp8T+jLa0zp389JQRnepmiY0k3Sjh0l8FmmMzPDWjs8N7DskbWJORZ45ZnnT4gJZIcm Da8ZQN2WjKAE1BUuBmAyMlgw/o2omNE= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-516-SfJ4gcIQOSazrJCdGOOvIw-1; Tue, 21 Nov 2023 05:40:43 -0500 X-MC-Unique: SfJ4gcIQOSazrJCdGOOvIw-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id ED10438107A3; Tue, 21 Nov 2023 10:40:42 +0000 (UTC) Received: from localhost (unknown [10.39.208.10]) by smtp.corp.redhat.com (Postfix) with ESMTP id 238E9492BE0; Tue, 21 Nov 2023 10:40:41 +0000 (UTC) From: marcandre.lureau@redhat.com To: qemu-devel@nongnu.org Cc: Gerd Hoffmann , Paolo Bonzini , =?utf-8?q?Marc-Andr=C3=A9_Lureau?= , peter.maydell@linaro.org, dwmw@amazon.co.uk, Manos Pitsidianakis Subject: [PULL 5/5] ui/pixman-minimal.h: fix empty allocation Date: Tue, 21 Nov 2023 14:40:20 +0400 Message-ID: <20231121104020.2209345-6-marcandre.lureau@redhat.com> In-Reply-To: <20231121104020.2209345-1-marcandre.lureau@redhat.com> References: <20231121104020.2209345-1-marcandre.lureau@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.9 Received-SPF: pass client-ip=170.10.133.124; envelope-from=marcandre.lureau@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.035, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org From: Manos Pitsidianakis In the minimal pixman API stub that is used when the real pixman dependency is missing a NULL dereference happens when virtio-gpu-rutabaga allocates a pixman image with bits = NULL and rowstride_bytes = zero. A buffer of rowstride_bytes * height is allocated which is NULL. However, in that scenario pixman calculates a new stride value based on given width, height and format size. This commit adds a helper function that performs the same logic as pixman. Signed-off-by: Manos Pitsidianakis Reviewed-by: Marc-André Lureau Message-Id: <20231121093840.2121195-1-manos.pitsidianakis@linaro.org> --- include/ui/pixman-minimal.h | 48 +++++++++++++++++++++++++++++++++++-- 1 file changed, 46 insertions(+), 2 deletions(-) diff --git a/include/ui/pixman-minimal.h b/include/ui/pixman-minimal.h index efcf570c9e..6dd7de1c7e 100644 --- a/include/ui/pixman-minimal.h +++ b/include/ui/pixman-minimal.h @@ -113,6 +113,45 @@ typedef struct pixman_color { uint16_t alpha; } pixman_color_t; +static inline uint32_t *create_bits(pixman_format_code_t format, + int width, + int height, + int *rowstride_bytes) +{ + int stride = 0; + size_t buf_size = 0; + int bpp = PIXMAN_FORMAT_BPP(format); + + /* + * Calculate the following while checking for overflow truncation: + * stride = ((width * bpp + 0x1f) >> 5) * sizeof(uint32_t); + */ + + if (unlikely(__builtin_mul_overflow(width, bpp, &stride))) { + return NULL; + } + + if (unlikely(__builtin_add_overflow(stride, 0x1f, &stride))) { + return NULL; + } + + stride >>= 5; + + stride *= sizeof(uint32_t); + + if (unlikely(__builtin_mul_overflow((size_t) height, + (size_t) stride, + &buf_size))) { + return NULL; + } + + if (rowstride_bytes) { + *rowstride_bytes = stride; + } + + return g_malloc0(buf_size); +} + static inline pixman_image_t *pixman_image_create_bits(pixman_format_code_t format, int width, int height, @@ -123,13 +162,18 @@ static inline pixman_image_t *pixman_image_create_bits(pixman_format_code_t form i->width = width; i->height = height; - i->stride = rowstride_bytes ?: width * DIV_ROUND_UP(PIXMAN_FORMAT_BPP(format), 8); i->format = format; if (bits) { i->data = bits; } else { - i->free_me = i->data = g_malloc0(rowstride_bytes * height); + i->free_me = i->data = + create_bits(format, width, height, &rowstride_bytes); + if (width && height) { + assert(i->data); + } } + i->stride = rowstride_bytes ? rowstride_bytes : + width * DIV_ROUND_UP(PIXMAN_FORMAT_BPP(format), 8); i->ref_count = 1; return i;