From 17fc6d054e41444b64b3f56bdca60b2765402071 Mon Sep 17 00:00:00 2001 From: oehhar Date: Sun, 3 Feb 2019 11:21:11 +0000 Subject: [PATCH 644/693] gif read not complete on overflow image - information missinterpreted if following subimage is querried [4da2191b] --- generic/tkImgGIF.c | 21 ++++++++++++++++++++- tests/imgPhoto.test | 33 +++++++++++++++++++++++++++++++++ 2 files changed, 53 insertions(+), 1 deletion(-) diff --git a/generic/tkImgGIF.c b/generic/tkImgGIF.c index 7c4872bef..fa4b728d3 100644 --- a/generic/tkImgGIF.c +++ b/generic/tkImgGIF.c @@ -1034,7 +1034,7 @@ ReadImage( int transparent) { unsigned char initialCodeSize; - int xpos = 0, ypos = 0, pass = 0, i; + int xpos = 0, ypos = 0, pass = 0, i, count; register unsigned char *pixelPtr; static const int interlaceStep[] = { 8, 8, 4, 2 }; static const int interlaceStart[] = { 0, 4, 2, 1 }; @@ -1252,6 +1252,25 @@ ReadImage( } pixelPtr = imagePtr + (ypos) * len * ((transparent>=0)?4:3); } + + /* + * Now read until the final zero byte. + * It was observed that there might be 1 length blocks + * (test imgPhoto-14.1) which are not read. + * + * The field "stack" is abused for temporary buffer. it has 4096 bytes + * and we need 256. + * + * Loop until we hit a 0 length block which is the end sign. + */ + while ( 0 < (count = GetDataBlock(gifConfPtr, chan, stack))) + { + if (-1 == count ) { + Tcl_SetObjResult(interp, Tcl_ObjPrintf( + "error reading GIF image: %s", Tcl_PosixError(interp))); + return TCL_ERROR; + } + } return TCL_OK; } -- 2.19.1