From mboxrd@z Thu Jan 1 00:00:00 1970 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 57EB0C5ACB3 for ; Tue, 21 Nov 2023 09:49:54 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1r5NNq-0007Nh-26; Tue, 21 Nov 2023 04:49:30 -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 1r5NNo-0007NQ-It for qemu-devel@nongnu.org; Tue, 21 Nov 2023 04:49:28 -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 1r5NNm-0006uM-AU for qemu-devel@nongnu.org; Tue, 21 Nov 2023 04:49:27 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1700560165; 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=/KltjkrelcEQboa71QBmxPYK95DuZpJn3ckJFb868yE=; b=QYeSai/AIPkz1nb7RJUQ/nDG6gTNBjdhh6cFfCXolouyxNf5ntoAUZraLEeuFOilTwSOII JyyIVqVQo/xv/H6Brqj3rnV3rH9kc4MGXxt7fnhP3KzATHYG+xLFJ9OHTIzQHN/ZeD40gR InkpRs5C/WmMq1RRBhVrrWE1Q9ULYfU= Received: from mail-ed1-f71.google.com (mail-ed1-f71.google.com [209.85.208.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-526-z23LOg1TPUOvV9lJRfK6yw-1; Tue, 21 Nov 2023 04:49:24 -0500 X-MC-Unique: z23LOg1TPUOvV9lJRfK6yw-1 Received: by mail-ed1-f71.google.com with SMTP id 4fb4d7f45d1cf-548ef4e9e89so775664a12.3 for ; Tue, 21 Nov 2023 01:49:23 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1700560162; x=1701164962; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=/KltjkrelcEQboa71QBmxPYK95DuZpJn3ckJFb868yE=; b=vuF1TWDBnDLTlaThXrCzWhwqhMTR9Xrx8l2hKp7hb6rORIs2VFFGlleT0oxfgdZJWs 7gZ/Luf8Os7wfl1lTTV5CS8hjir5xJjejJRHwbXNLfdSVF7D+okRKhrnNiu1c2PlRNi/ cL57L8/hHpU7fBYIiWyPcESkV7qvsKYrH8AwRtI8oXIkKKkV+bnRK1qf8sS0iPytOx2F fgN8oZ6e/hohrrYGD5sG1z36b6VDhz+e8KNbgdbZPTsN9n+yOKAIe9908J80Hw4dlsn3 o8d2QXl1Uvw4Ydbh5vIZHYvpt8bStzpCwhr/1WhcANHGP2r5gx8+MY+5xJTe92pGcgPo qd3Q== X-Gm-Message-State: AOJu0YxySBzIdjBQ2cJrh6KWZbyl/1OTqKqvvrWFaK64Nw8zYOGQLaW3 lBVYmDaPo+wJaaLVQ3bcpnbumG06DKtmKRl6r4milU7dMrZ/gjR98Y5ujglJNG+/X+hqBc/U6CD u1ha9P289GM0q3NfHT0p4PVB2odYqDtwbPiwhkCTqbw== X-Received: by 2002:a05:6402:616:b0:548:ac1f:54ff with SMTP id n22-20020a056402061600b00548ac1f54ffmr1316072edv.41.1700560161964; Tue, 21 Nov 2023 01:49:21 -0800 (PST) X-Google-Smtp-Source: AGHT+IFTotIg+PUqdmRodkpPmVq91GW/xTHzLing0VmWgMmBGqnOC9vJKMwBXhbidfmEO+20pJwvrWgl6/gUTMfUN6Y= X-Received: by 2002:a05:6402:616:b0:548:ac1f:54ff with SMTP id n22-20020a056402061600b00548ac1f54ffmr1316065edv.41.1700560161637; Tue, 21 Nov 2023 01:49:21 -0800 (PST) MIME-Version: 1.0 References: <20231121093840.2121195-1-manos.pitsidianakis@linaro.org> In-Reply-To: <20231121093840.2121195-1-manos.pitsidianakis@linaro.org> From: =?UTF-8?B?TWFyYy1BbmRyw6kgTHVyZWF1?= Date: Tue, 21 Nov 2023 13:49:10 +0400 Message-ID: Subject: Re: [PATCH for-8.2] ui/pixman-minimal.h: fix empty allocation To: Manos Pitsidianakis Cc: qemu-devel@nongnu.org, Gerd Hoffmann Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Received-SPF: pass client-ip=170.10.133.124; envelope-from=mlureau@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 Hi Manos On Tue, Nov 21, 2023 at 1:38=E2=80=AFPM Manos Pitsidianakis wrote: > > 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 =3D NULL and > rowstride_bytes =3D 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. > Thanks a lot for investigating this and providing a solution! Reviewed-by: Marc-Andr=C3=A9 Lureau > Signed-off-by: Manos Pitsidianakis > --- > 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 =3D 0; > + size_t buf_size =3D 0; > + int bpp =3D PIXMAN_FORMAT_BPP(format); > + > + /* > + * Calculate the following while checking for overflow truncation: > + * stride =3D ((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 >>=3D 5; > + > + stride *=3D sizeof(uint32_t); > + > + if (unlikely(__builtin_mul_overflow((size_t) height, > + (size_t) stride, > + &buf_size))) { > + return NULL; > + } > + > + if (rowstride_bytes) { > + *rowstride_bytes =3D stride; > + } > + > + return g_malloc0(buf_size); > +} > + > static inline pixman_image_t *pixman_image_create_bits(pixman_format_cod= e_t format, > int width, > int height, > @@ -123,13 +162,18 @@ static inline pixman_image_t *pixman_image_create_b= its(pixman_format_code_t form > > i->width =3D width; > i->height =3D height; > - i->stride =3D rowstride_bytes ?: width * DIV_ROUND_UP(PIXMAN_FORMAT_= BPP(format), 8); > i->format =3D format; > if (bits) { > i->data =3D bits; > } else { > - i->free_me =3D i->data =3D g_malloc0(rowstride_bytes * height); > + i->free_me =3D i->data =3D > + create_bits(format, width, height, &rowstride_bytes); > + if (width && height) { > + assert(i->data); > + } > } > + i->stride =3D rowstride_bytes ? rowstride_bytes : > + width * DIV_ROUND_UP(PIXMAN_FORMAT_BPP(forma= t), 8); > i->ref_count =3D 1; > > return i; > > base-commit: af9264da80073435fd78944bc5a46e695897d7e5 > -- > 2.39.2 >