From 1616c71921b73b227f56ccb3f2c49a994ec23440 Mon Sep 17 00:00:00 2001 From: Allan Sandfeld Jensen Date: Thu, 23 Jul 2020 11:48:48 +0200 Subject: Fix buffer overflow in XBM parser Avoid parsing over the buffer limit, or interpreting non-hex as hex. This still leaves parsing of lines longer than 300 chars unreliable Change-Id: I1c57a7e530c4380f6f9040b2ec729ccd7dc7a5fb Reviewed-by: Robert Loehning Reviewed-by: Eirik Aavitsland (cherry picked from commit c562c1fc19629fb505acd0f6380604840b634211) Reviewed-by: Qt Cherry-pick Bot --- src/gui/image/qxbmhandler.cpp | 4 ++- .../gui/image/qimagereader/tst_qimagereader.cpp | 38 ++++++++++++++++++++++ 2 files changed, 41 insertions(+), 1 deletion(-) diff --git a/src/gui/image/qxbmhandler.cpp b/src/gui/image/qxbmhandler.cpp index f06561690c..72ce7f7ecd 100644 --- a/src/gui/image/qxbmhandler.cpp +++ b/src/gui/image/qxbmhandler.cpp @@ -159,7 +159,9 @@ static bool read_xbm_body(QIODevice *device, int w, int h, QImage *outImage) w = (w+7)/8; // byte width while (y < h) { // for all encoded bytes... - if (p) { // p = "0x.." + if (p && p < (buf + readBytes - 3)) { // p = "0x.." + if (!isxdigit(p[2]) || !isxdigit(p[3])) + return false; *b++ = hex2byte(p+2); p += 2; if (++x == w && ++y < h) { -- cgit v1.2.1