From 399719595f413158b3510128eb85f944654f960c Mon Sep 17 00:00:00 2001 From: DRC Date: Tue, 12 Jun 2018 20:27:00 -0500 Subject: [PATCH] tjLoadImage(): Fix FPE triggered by malformed BMP In rdbmp.c, it is necessary to guard against 32-bit overflow/wraparound when allocating the row buffer, because since BMP files have 32-bit width and height fields, the value of biWidth can be up to 4294967295. Specifically, if biWidth is 1073741824 and cinfo->input_components = 4, then the samplesperrow argument in alloc_sarray() would wrap around to 0, and a division by zero error would occur at line 458 in jmemmgr.c. If biWidth is set to a higher value, then samplesperrow would wrap around to a small number, which would likely cause a buffer overflow (this has not been tested or verified.) --- rdbmp.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/rdbmp.c b/rdbmp.c index eaa7086..4104b68 100644 --- a/rdbmp.c +++ b/rdbmp.c @@ -434,6 +434,12 @@ start_input_bmp (j_compress_ptr cinfo, cjpeg_source_ptr sinfo) progress->total_extra_passes++; /* count file input as separate pass */ } + /* Ensure that biWidth * cinfo->input_components doesn't exceed the maximum + value of the JDIMENSION type. This is only a danger with BMP files, since + their width and height fields are 32-bit integers. */ + if ((unsigned long long)biWidth * + (unsigned long long)cinfo->input_components > 0xFFFFFFFFULL) + ERREXIT(cinfo, JERR_WIDTH_OVERFLOW); /* Allocate one-row buffer for returned data */ source->pub.buffer = (*cinfo->mem->alloc_sarray) ((j_common_ptr) cinfo, JPOOL_IMAGE, -- 2.17.1