From da325c45d9df54f359e6a22ee9ad820994e3cd47 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Fri, 18 Nov 2022 18:26:59 +0100 Subject: avcodec/tiff: Ignore tile_count Fixes: out of array access Fixes: 52427/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_TIFF_fuzzer-4849108968144896 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer (cherry picked from commit 65ce417828cc6f5209d8467bc7755f0c59e9aa49) Signed-off-by: Michael Niedermayer --- libavcodec/tiff.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/libavcodec/tiff.c b/libavcodec/tiff.c index f66268568d..49ae252e3b 100644 --- a/libavcodec/tiff.c +++ b/libavcodec/tiff.c @@ -100,7 +100,6 @@ typedef struct TiffContext { int is_tiled; int tile_byte_counts_offset, tile_offsets_offset; int tile_width, tile_length; - int tile_count; int is_jpeg; @@ -974,7 +973,7 @@ static int dng_decode_tiles(AVCodecContext *avctx, AVFrame *frame, tile_count_y = (s->height + s->tile_length - 1) / s->tile_length; /* Iterate over the number of tiles */ - for (tile_idx = 0; tile_idx < s->tile_count; tile_idx++) { + for (tile_idx = 0; tile_idx < tile_count_x * tile_count_y; tile_idx++) { tile_x = tile_idx % tile_count_x; tile_y = tile_idx / tile_count_x; @@ -1394,7 +1393,6 @@ static int tiff_decode_tag(TiffContext *s, AVFrame *frame) break; case TIFF_TILE_OFFSETS: s->tile_offsets_offset = off; - s->tile_count = count; s->is_tiled = 1; break; case TIFF_TILE_BYTE_COUNTS: @@ -1889,7 +1887,7 @@ again: return AVERROR_INVALIDDATA; } - has_tile_bits = s->is_tiled || s->tile_byte_counts_offset || s->tile_offsets_offset || s->tile_width || s->tile_length || s->tile_count; + has_tile_bits = s->is_tiled || s->tile_byte_counts_offset || s->tile_offsets_offset || s->tile_width || s->tile_length; has_strip_bits = s->strippos || s->strips || s->stripoff || s->rps || s->sot || s->sstype || s->stripsize || s->stripsizesoff; if (has_tile_bits && has_strip_bits) { -- cgit v1.2.1