From patchwork Tue Dec 22 09:39:38 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeremy Leconte X-Patchwork-Id: 24621 Return-Path: X-Original-To: patchwork@ffaux-bg.ffmpeg.org Delivered-To: patchwork@ffaux-bg.ffmpeg.org Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org [79.124.17.100]) by ffaux.localdomain (Postfix) with ESMTP id C5C0B448ADB for ; Tue, 22 Dec 2020 11:40:10 +0200 (EET) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 9B87A68A817; Tue, 22 Dec 2020 11:40:10 +0200 (EET) X-Original-To: ffmpeg-devel@ffmpeg.org Delivered-To: ffmpeg-devel@ffmpeg.org Received: from mail-wm1-f73.google.com (mail-wm1-f73.google.com [209.85.128.73]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 0A60268A255 for ; Tue, 22 Dec 2020 11:40:04 +0200 (EET) Received: by mail-wm1-f73.google.com with SMTP id b184so1230726wmh.6 for ; Tue, 22 Dec 2020 01:40:04 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:message-id:mime-version:subject:from:to:cc; bh=VNd2VdQZ07q30EP2OeYYzzyg6EEjIotw308vCigQo/0=; b=wUsBrykHcgvw78Iz1+pgBSfdXTL19r8oTRoVmoq/zXJwiIrPTgUQ0qLHIv+4lNDVm9 MCQPifq7umFed/xaHvt26KudKEoYhQwF+irhEcnwW+WqTXO7aZo96Rz0PXLobRbhYG1T 4vM7pNMOUvUjx26rM0BL1OGBg68HLkKAe18+oUkjiYv9/EtiSUl0G9rQwFRCsLcXGSj7 1JTX2b4/jLh+MVCq/+rau+6cUvdmyvF2Lfa4Cf/s9wjaXxHafiSHHrHJTU6aj751367A wWwYe4hTfBGZ20e/qDTBPiCRyjyCc83Ho+hgeNb3aEzXIs0oa3bUjx2LodR0SWRE9fmq EsJw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:message-id:mime-version:subject:from :to:cc; bh=VNd2VdQZ07q30EP2OeYYzzyg6EEjIotw308vCigQo/0=; b=AvF9sZvvwHoKe67iafOsc1XSYV0E91CbvH1NfDtZmC6HV2d8SHSBNveir36OJTtb8U MjTXZiX4YjFGjp+3q39roBAp0jqcoNnIF7+w9NKw5uA++51Ld6JBGeho5qnRjfkDg+vU KPQyCiKe0V53C53oWTPEzC+RFtMvIOMYVy9eMqe+FtlHFc/Jwf67wpgbjpJOQPfVbLej pbxvqp9hyYexaAy4qd2ve3VmZaGUQNTqADV5cbN/AQD5fuve2dI75FCCyNTxbow5QXVE F0S+0tT51hbtAtvwMGP0OB2SYb34ZWye3ifB5qYJ+cdXjVUVbIqHsN/upnHcwbqX1MRi Pb9Q== X-Gm-Message-State: AOAM532aFE7hUZUfmVEzUNH6lh03uBJ3mwaSsqNd3Sn/SCb+cwkg9mdk l6oZ22zrSjZ8EXh0DCffe65SYZa3CkwDW13Swq+3fBwfZwOx/ntwHf929cjNNnRXRrWDKrjLNQM b9I+31I7dHqs89+V3nDQCcZLn6XyGUmsH6cYwcgDXeKPFHpuGjPylUjT/BQ2lwEIU/puI X-Google-Smtp-Source: ABdhPJz9T4jp9M6sOj806DqZQr2DZr8kIuZGFQZW2MP4TU1EDL6PAsl7qZ9QN9QRM/o6/4K5mVmnvb5uNJ6wWQ== X-Received: from jleconte.c.googlers.com ([fda3:e722:ac3:cc00:28:9cb1:c0a8:c68]) (user=jleconte job=sendgmr) by 2002:adf:cc81:: with SMTP id p1mr22884322wrj.339.1608630003384; Tue, 22 Dec 2020 01:40:03 -0800 (PST) Date: Tue, 22 Dec 2020 09:39:38 +0000 Message-Id: <20201222093937.515792-1-jleconte@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.29.2.729.g45daf8777d-goog From: jleconte To: ffmpeg-devel@ffmpeg.org Subject: [FFmpeg-devel] [PATCH] libswscale: avoid UB nullptr-with-offset. X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: FFmpeg development discussions and patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: FFmpeg development discussions and patches Cc: jleconte Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Thanks for the feedback. It's not easy to work with -Wdeclaration-after-statement. --- libswscale/slice.c | 12 ++++-------- libswscale/swscale_unscaled.c | 4 +--- 2 files changed, 5 insertions(+), 11 deletions(-) diff --git a/libswscale/slice.c b/libswscale/slice.c index 7849b70f4d..d96db13364 100644 --- a/libswscale/slice.c +++ b/libswscale/slice.c @@ -158,14 +158,10 @@ int ff_init_slice_from_src(SwsSlice * s, uint8_t *src[4], int stride[4], int src chrY + chrH, lumY + lumH}; - uint8_t *const src_[4] = {src[0] + (relative ? 0 : start[0]) * stride[0], - src[1] + (relative ? 0 : start[1]) * stride[1], - src[2] + (relative ? 0 : start[2]) * stride[2], - src[3] + (relative ? 0 : start[3]) * stride[3]}; - s->width = srcW; - for (i = 0; i < 4; ++i) { + for (i = 0; i < 4 && src[i] != NULL; ++i) { + uint8_t *const src_i = src[i] + (relative ? 0 : start[i]) * stride[i]; int j; int first = s->plane[i].sliceY; int n = s->plane[i].available_lines; @@ -175,13 +171,13 @@ int ff_init_slice_from_src(SwsSlice * s, uint8_t *src[4], int stride[4], int src if (start[i] >= first && n >= tot_lines) { s->plane[i].sliceH = FFMAX(tot_lines, s->plane[i].sliceH); for (j = 0; j < lines; j+= 1) - s->plane[i].line[start[i] - first + j] = src_[i] + j * stride[i]; + s->plane[i].line[start[i] - first + j] = src_i + j * stride[i]; } else { s->plane[i].sliceY = start[i]; lines = lines > n ? n : lines; s->plane[i].sliceH = lines; for (j = 0; j < lines; j+= 1) - s->plane[i].line[j] = src_[i] + j * stride[i]; + s->plane[i].line[j] = src_i + j * stride[i]; } } diff --git a/libswscale/swscale_unscaled.c b/libswscale/swscale_unscaled.c index 563de39696..7e92f3fafc 100644 --- a/libswscale/swscale_unscaled.c +++ b/libswscale/swscale_unscaled.c @@ -1805,7 +1805,7 @@ static int planarCopyWrapper(SwsContext *c, const uint8_t *src[], const AVPixFmtDescriptor *desc_src = av_pix_fmt_desc_get(c->srcFormat); const AVPixFmtDescriptor *desc_dst = av_pix_fmt_desc_get(c->dstFormat); int plane, i, j; - for (plane = 0; plane < 4; plane++) { + for (plane = 0; plane < 4 && dst[plane] != NULL; plane++) { int length = (plane == 0 || plane == 3) ? c->srcW : AV_CEIL_RSHIFT(c->srcW, c->chrDstHSubSample); int y = (plane == 0 || plane == 3) ? srcSliceY: AV_CEIL_RSHIFT(srcSliceY, c->chrDstVSubSample); int height = (plane == 0 || plane == 3) ? srcSliceH: AV_CEIL_RSHIFT(srcSliceH, c->chrDstVSubSample); @@ -1813,8 +1813,6 @@ static int planarCopyWrapper(SwsContext *c, const uint8_t *src[], uint8_t *dstPtr = dst[plane] + dstStride[plane] * y; int shiftonly = plane == 1 || plane == 2 || (!c->srcRange && plane == 0); - if (!dst[plane]) - continue; // ignore palette for GRAY8 if (plane == 1 && !dst[2]) continue; if (!src[plane] || (plane == 1 && !src[2])) {