convertbmp: fix issues with zero bitmasks

In the case where a BMP file declares compression 3 (BI_BITFIELDS)
with header size <= 56, all bitmask values keep their initialization
value 0. This may lead to various undefined behavior later e.g. when
doing 1 << (l_comp->prec - 1).

This issue does not affect files with bit count 16 because of a check
added in 16240e2 which sets default values to the color masks if they
are all 0.

This commit adds similar checks for the 32 bit case.

Also, if a BMP file declares compression 3 with header size >= 56 and
intentional 0 bitmasks, the same issue will be triggered in both the
16 and 32 bit count case.

This commit adds checks to bmp_read_info_header() rejecting BMP files
with "intentional" 0 bitmasks. These checks might be removed in the
future when proper handling of zero bitmasks will be available in
openjpeg2.

fixes #1057 (CVE-2018-5785)
This commit is contained in:
Hugo Lefeuvre 2018-09-22 14:33:19 -04:00
parent 9d1a9dc20d
commit ca16fe5501
1 changed files with 21 additions and 0 deletions

View File

@ -435,16 +435,31 @@ static OPJ_BOOL bmp_read_info_header(FILE* IN, OPJ_BITMAPINFOHEADER* header)
header->biRedMask |= (OPJ_UINT32)getc(IN) << 16;
header->biRedMask |= (OPJ_UINT32)getc(IN) << 24;
if (!header->biRedMask) {
fprintf(stderr, "Error, invalid red mask value %d\n", header->biRedMask);
return OPJ_FALSE;
}
header->biGreenMask = (OPJ_UINT32)getc(IN);
header->biGreenMask |= (OPJ_UINT32)getc(IN) << 8;
header->biGreenMask |= (OPJ_UINT32)getc(IN) << 16;
header->biGreenMask |= (OPJ_UINT32)getc(IN) << 24;
if (!header->biGreenMask) {
fprintf(stderr, "Error, invalid green mask value %d\n", header->biGreenMask);
return OPJ_FALSE;
}
header->biBlueMask = (OPJ_UINT32)getc(IN);
header->biBlueMask |= (OPJ_UINT32)getc(IN) << 8;
header->biBlueMask |= (OPJ_UINT32)getc(IN) << 16;
header->biBlueMask |= (OPJ_UINT32)getc(IN) << 24;
if (!header->biBlueMask) {
fprintf(stderr, "Error, invalid blue mask value %d\n", header->biBlueMask);
return OPJ_FALSE;
}
header->biAlphaMask = (OPJ_UINT32)getc(IN);
header->biAlphaMask |= (OPJ_UINT32)getc(IN) << 8;
header->biAlphaMask |= (OPJ_UINT32)getc(IN) << 16;
@ -831,6 +846,12 @@ opj_image_t* bmptoimage(const char *filename, opj_cparameters_t *parameters)
bmpmask32toimage(pData, stride, image, 0x00FF0000U, 0x0000FF00U, 0x000000FFU,
0x00000000U);
} else if (Info_h.biBitCount == 32 && Info_h.biCompression == 3) { /* bitmask */
if ((Info_h.biRedMask == 0U) && (Info_h.biGreenMask == 0U) &&
(Info_h.biBlueMask == 0U)) {
Info_h.biRedMask = 0x00FF0000U;
Info_h.biGreenMask = 0x0000FF00U;
Info_h.biBlueMask = 0x000000FFU;
}
bmpmask32toimage(pData, stride, image, Info_h.biRedMask, Info_h.biGreenMask,
Info_h.biBlueMask, Info_h.biAlphaMask);
} else if (Info_h.biBitCount == 16 && Info_h.biCompression == 0) { /* RGBX */