From patchwork Thu May 16 22:29:56 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andreas Rheinhardt X-Patchwork-Id: 13177 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 AC7FE449B3C for ; Fri, 17 May 2019 01:51:22 +0300 (EEST) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 99A5068A70E; Fri, 17 May 2019 01:51:22 +0300 (EEST) X-Original-To: ffmpeg-devel@ffmpeg.org Delivered-To: ffmpeg-devel@ffmpeg.org Received: from mail-wm1-f67.google.com (mail-wm1-f67.google.com [209.85.128.67]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 7348668A74B for ; Fri, 17 May 2019 01:51:20 +0300 (EEST) Received: by mail-wm1-f67.google.com with SMTP id f204so5155429wme.0 for ; Thu, 16 May 2019 15:51:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=/9r3XuXlpGaDkgNXy322WYbLuXMznh/Vjlw0fwJ/py4=; b=MTeMq6cFao18dk6MAto3383iukvuksPJ6d3jBORdr2zrJBdgQzlsYEKrVR96tG3Ma9 ssKR6FmMid5AAPLfmiRviOshY2NSdDu8t43RwgLchar2wdxQMdpj25Y9lmrf+C3v2zYi yGDpruLbhZbprUKScHv6j4XFP5zSl6kWLoGxQGKwGcjjBt8AFh2uFmPen6MYXObvAYLF RHLeGn1oe1pB/2D/RqDDa11QF5yxzTToiRVB8Ieqlb61WD4/SpLdlstUYpU6wrx3Cox6 q4JE0YABBZwD2tCOlqDjBeVtospYgpGEbv4bxfVT5WjzeYFLZk2Cb5aZmGva1Ic+gMGU 14Ig== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=/9r3XuXlpGaDkgNXy322WYbLuXMznh/Vjlw0fwJ/py4=; b=BC8Typ5NhR44/7yP10qj72ht1ma7UubkKKGlrl0Q4ize7SIAiWbos++8HbgNwK5jMT mObFYePlFZWV28PaQv7Ie6W6Dq+XUftDukMTkwXExbbatB6ShVwaJoWVdxHogMlbci6l 27/JMKB8WWx/xcDGwym/gLwUxVjYxqbqoV3o+rKG8VO2pGFZTmU3J59vpRNSib7o5Rlx MHF8rtLQJn5Db/95Ox4xaxQ7iMffoLjjI7pHlcyxAKCGDwWi6shHylMCeFSd3ZVPynxL doz88Qf496PBZEz7x4xOWf/cBco1KXfFBot9dDt4xuc/BXMf+6m5Au+8KcLJ2YmjQ55f aJ5Q== X-Gm-Message-State: APjAAAWzXzyzF6OEXDYpECmavW8lW9TB0RIJ/MoSwEfOPu3MNXpQD6Ek 1coPys7/Ec8mr2wgoDzMaRHJ3xxa X-Google-Smtp-Source: APXvYqyxjDB6ltkAx7ABBrSpzXZnaoEtWjW8uD5/uexRe0n6Bon6dnl0QAByCp15JavU4Z0tW2f1Aw== X-Received: by 2002:a1c:e1d7:: with SMTP id y206mr92128wmg.104.1558046591826; Thu, 16 May 2019 15:43:11 -0700 (PDT) Received: from localhost.localdomain (ipbcc18715.dynamic.kabel-deutschland.de. [188.193.135.21]) by smtp.gmail.com with ESMTPSA id i185sm11168725wmg.32.2019.05.16.15.43.11 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 16 May 2019 15:43:11 -0700 (PDT) From: Andreas Rheinhardt To: ffmpeg-devel@ffmpeg.org Date: Fri, 17 May 2019 00:29:56 +0200 Message-Id: <20190516223018.30827-13-andreas.rheinhardt@gmail.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190516223018.30827-1-andreas.rheinhardt@gmail.com> References: <20190516223018.30827-1-andreas.rheinhardt@gmail.com> MIME-Version: 1.0 Subject: [FFmpeg-devel] [PATCH 12/37] avformat/matroskadec: Improve read error/EOF checks II 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: Andreas Rheinhardt Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" This commit fixes a number of bugs: 1. There was no check that no read error/EOF occured during ebml_read_uint, ebml_read_sint and ebml_read_float. 2. ebml_read_ascii and ebml_read_binary did sometimes not forward error codes; instead they simply returned AVERROR(EIO). 3. In particular, AVERROR_EOF hasn't been used and no dedicated error message for it existed. This has been changed. In order to reduce code duplication, the new error code NEEDS_CHECKING has been introduced which makes ebml_parse check the AVIOContext's status for errors. Signed-off-by: Andreas Rheinhardt --- libavformat/matroskadec.c | 59 ++++++++++++++++++++++++++------------- 1 file changed, 40 insertions(+), 19 deletions(-) diff --git a/libavformat/matroskadec.c b/libavformat/matroskadec.c index 431e742a2d..3f11f60878 100644 --- a/libavformat/matroskadec.c +++ b/libavformat/matroskadec.c @@ -69,6 +69,8 @@ #include "qtpalette.h" #define EBML_UNKNOWN_LENGTH UINT64_MAX /* EBML unknown length, in uint64_t */ +#define NEEDS_CHECKING 2 /* Indicates that some error checks + * still need to be performed */ typedef enum { EBML_NONE, @@ -891,7 +893,7 @@ static int ebml_read_length(MatroskaDemuxContext *matroska, AVIOContext *pb, /* * Read the next element as an unsigned int. - * 0 is success, < 0 is failure. + * Returns NEEDS_CHECKING. */ static int ebml_read_uint(AVIOContext *pb, int size, uint64_t *num) { @@ -902,12 +904,12 @@ static int ebml_read_uint(AVIOContext *pb, int size, uint64_t *num) while (n++ < size) *num = (*num << 8) | avio_r8(pb); - return 0; + return NEEDS_CHECKING; } /* * Read the next element as a signed int. - * 0 is success, < 0 is failure. + * Returns NEEDS_CHECKING. */ static int ebml_read_sint(AVIOContext *pb, int size, int64_t *num) { @@ -923,12 +925,12 @@ static int ebml_read_sint(AVIOContext *pb, int size, int64_t *num) *num = ((uint64_t)*num << 8) | avio_r8(pb); } - return 0; + return NEEDS_CHECKING; } /* * Read the next element as a float. - * 0 is success, < 0 is failure. + * Returns NEEDS_CHECKING or < 0 on obvious failure. */ static int ebml_read_float(AVIOContext *pb, int size, double *num) { @@ -941,24 +943,25 @@ static int ebml_read_float(AVIOContext *pb, int size, double *num) else return AVERROR_INVALIDDATA; - return 0; + return NEEDS_CHECKING; } /* * Read the next element as an ASCII string. - * 0 is success, < 0 is failure. + * 0 is success, < 0 or NEEDS_CHECKING is failure. */ static int ebml_read_ascii(AVIOContext *pb, int size, char **str) { char *res; + int ret; /* EBML strings are usually not 0-terminated, so we allocate one * byte more, read the string and NULL-terminate it ourselves. */ if (!(res = av_malloc(size + 1))) return AVERROR(ENOMEM); - if (avio_read(pb, (uint8_t *) res, size) != size) { + if ((ret = avio_read(pb, (uint8_t *) res, size)) != size) { av_free(res); - return AVERROR(EIO); + return ret < 0 ? ret : NEEDS_CHECKING; } (res)[size] = '\0'; av_free(*str); @@ -969,7 +972,7 @@ static int ebml_read_ascii(AVIOContext *pb, int size, char **str) /* * Read the next element as binary data. - * 0 is success, < 0 is failure. + * 0 is success, < 0 or NEEDS_CHECKING is failure. */ static int ebml_read_binary(AVIOContext *pb, int length, EbmlBin *bin) { @@ -983,11 +986,11 @@ static int ebml_read_binary(AVIOContext *pb, int length, EbmlBin *bin) bin->data = bin->buf->data; bin->size = length; bin->pos = avio_tell(pb); - if (avio_read(pb, bin->data, length) != length) { + if ((ret = avio_read(pb, bin->data, length)) != length) { av_buffer_unref(&bin->buf); bin->data = NULL; bin->size = 0; - return AVERROR(EIO); + return ret < 0 ? ret : NEEDS_CHECKING; } return 0; @@ -1277,14 +1280,32 @@ static int ebml_parse_elem(MatroskaDemuxContext *matroska, case EBML_STOP: return 1; default: - if (ffio_limit(pb, length) != length) - return AVERROR(EIO); - return avio_skip(pb, length) < 0 ? AVERROR(EIO) : 0; + if (ffio_limit(pb, length) != length) { + // ffio_limit emits its own error message, + // so we don't have to. + return AVERROR_EOF; + } + res = avio_skip(pb, length); + res = res < 0 ? res : 0; + } + if (res) { + if (res == NEEDS_CHECKING) { + if (pb->eof_reached) { + if (pb->error) + res = pb->error; + else + res = AVERROR_EOF; + } else + res = 0; + } + + if (res == AVERROR_INVALIDDATA) + av_log(matroska->ctx, AV_LOG_ERROR, "Invalid element\n"); + else if (res == AVERROR(EIO)) + av_log(matroska->ctx, AV_LOG_ERROR, "Read error\n"); + else if (res == AVERROR_EOF) + av_log(matroska->ctx, AV_LOG_ERROR, "File ended prematurely\n"); } - if (res == AVERROR_INVALIDDATA) - av_log(matroska->ctx, AV_LOG_ERROR, "Invalid element\n"); - else if (res == AVERROR(EIO)) - av_log(matroska->ctx, AV_LOG_ERROR, "Read error\n"); return res; }