From b4681bd6ecfb2fb4b4512a98e68edda536af7ca5 Mon Sep 17 00:00:00 2001 From: Marton Balint Date: Sat, 11 May 2024 22:54:24 +0200 Subject: [PATCH] avformat/mp3dec: only call ffio_ensure_seekback once Otherwise the subsequent ffio_ensure_seekback calls destroy the buffer of the earlier. The worst case ~66kB seekback is so small it is easier to request it entirely. Fixes ticket #10837, a regression since 0d17f5228f4d3854066ec1001f69c7d1714b0df9. Signed-off-by: Marton Balint (cherry picked from commit b0053172199b54a806a4147cda8567a2f1823bc0) --- libavformat/mp3dec.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/libavformat/mp3dec.c b/libavformat/mp3dec.c index 05c13228bc..6423becf35 100644 --- a/libavformat/mp3dec.c +++ b/libavformat/mp3dec.c @@ -32,6 +32,7 @@ #include "replaygain.h" #include "libavcodec/codec_id.h" +#include "libavcodec/mpegaudio.h" #include "libavcodec/mpegaudiodecheader.h" #define XING_FLAG_FRAMES 0x01 @@ -400,15 +401,16 @@ static int mp3_read_header(AVFormatContext *s) if (ret < 0) return ret; + ret = ffio_ensure_seekback(s->pb, 64 * 1024 + MPA_MAX_CODED_FRAME_SIZE + 4); + if (ret < 0) + return ret; + off = avio_tell(s->pb); for (i = 0; i < 64 * 1024; i++) { uint32_t header, header2; int frame_size; - if (!(i&1023)) - ffio_ensure_seekback(s->pb, i + 1024 + 4); frame_size = check(s->pb, off + i, &header); if (frame_size > 0) { - ffio_ensure_seekback(s->pb, i + 1024 + frame_size + 4); ret = check(s->pb, off + i + frame_size, &header2); if (ret >= 0 && (header & MP3_MASK) == (header2 & MP3_MASK))