cheng/libtiff
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

tif_ojpeg.c: avoid use of uninitialized memory on edge/broken file. Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=16844

Browse Source
This commit is contained in:
Even Rouault 2019-09-02 16:21:02 +02:00
parent 4b2a343001
commit 7475a28508
No known key found for this signature in database
GPG Key ID: 33EBBFC47B3DD87D
1 changed files with 7 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
libtiff/tif_ojpeg.c
View File

@ -1241,7 +1241,13 @@ OJPEGWriteHeaderInfo(TIFF* tif)
sp->subsampling_convert_ybuflen=sp->subsampling_convert_ylinelen*sp->subsampling_convert_ylines; sp->subsampling_convert_ybuflen=sp->subsampling_convert_ylinelen*sp->subsampling_convert_ylines;
sp->subsampling_convert_cbuflen=sp->subsampling_convert_clinelen*sp->subsampling_convert_clines; sp->subsampling_convert_cbuflen=sp->subsampling_convert_clinelen*sp->subsampling_convert_clines;
sp->subsampling_convert_ycbcrbuflen=sp->subsampling_convert_ybuflen+2*sp->subsampling_convert_cbuflen; sp->subsampling_convert_ycbcrbuflen=sp->subsampling_convert_ybuflen+2*sp->subsampling_convert_cbuflen;
sp->subsampling_convert_ycbcrbuf=_TIFFmalloc(sp->subsampling_convert_ycbcrbuflen); /* The calloc is not normally necessary, except in some edge/broken cases */
/* for example for a tiled image of height 1 with a tile height of 1 and subsampling_hor=subsampling_ver=2 */
/* In that case, libjpeg will only fill the 8 first lines of the 16 lines */
/* See https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=16844 */
/* Even if this case is allowed (?), its handling is broken because OJPEGPreDecode() should also likely */
/* reset subsampling_convert_state to 0 when changing tile. */
sp->subsampling_convert_ycbcrbuf=_TIFFcalloc(1, sp->subsampling_convert_ycbcrbuflen);
if (sp->subsampling_convert_ycbcrbuf==0) if (sp->subsampling_convert_ycbcrbuf==0)
{ {
TIFFErrorExt(tif->tif_clientdata,module,"Out of memory"); TIFFErrorExt(tif->tif_clientdata,module,"Out of memory");