mirror/opencv
1
0
Fork 0
mirror of https://github.com/opencv/opencv.git synced 2025-08-06 14:36:36 +08:00
Code Issues Actions Packages Projects Releases Wiki Activity

Merge pull request #7452 from reunanen:issue-7409-2.4

Browse Source 
Fix findContours crash for very large images (v2.4)

* Cast step to size_t in order to avoid integer overflow when processing very large images

* Change assert to CV_Assert
This commit is contained in:
Juha Reunanen 2016-10-12 10:37:07 +03:00 committed by Alexander Alekhin
parent c7c831bca5
commit 4e7f28811c
1 changed files with 11 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
modules/imgproc/src/contours.cpp
View File

@ -284,10 +284,13 @@ cvStartFindContours( void* _img, CvMemStorage* storage,
scanner->cinfo_storage );
}
CV_Assert(step >= 0);
CV_Assert(size.height >= 1);
/* make zero borders */
int esz = CV_ELEM_SIZE(mat->type);
memset( img, 0, size.width*esz );
memset( img + step * (size.height - 1), 0, size.width*esz );
memset( img + static_cast<size_t>(step) * (size.height - 1), 0, size.width*esz );
img += step;
for( int y = 1; y < size.height - 1; y++, img += step )
@ -989,6 +992,8 @@ cvFindNextContour( CvContourScanner scanner )
{
if( !scanner )
CV_Error( CV_StsNullPtr, "" );
CV_Assert(scanner->img_step >= 0);
icvEndProcessContour( scanner );
/* initialize local state */
@ -1063,7 +1068,7 @@ cvFindNextContour( CvContourScanner scanner )
is_hole = 1;
}
if( mode == 0 && (is_hole || img0[lnbd.y * step + lnbd.x] > 0) )
if( mode == 0 && (is_hole || img0[lnbd.y * static_cast<size_t>(step) + lnbd.x] > 0) )
goto resume_scan;
origin.y = y;
@ -1077,8 +1082,8 @@ cvFindNextContour( CvContourScanner scanner )
else
{
int lval = (img0_i ?
img0_i[lnbd.y * step_i + lnbd.x] :
(int)img0[lnbd.y * step + lnbd.x]) & 0x7f;
img0_i[lnbd.y * static_cast<size_t>(step_i) + lnbd.x] :
(int)img0[lnbd.y * static_cast<size_t>(step) + lnbd.x]) & 0x7f;
_CvContourInfo *cur = scanner->cinfo_table[lval];
/* find the first bounding contour */
@ -1090,11 +1095,11 @@ cvFindNextContour( CvContourScanner scanner )
if( par_info )
{
if( (img0_i &&
icvTraceContour_32s( img0_i + par_info->origin.y * step_i +
icvTraceContour_32s( img0_i + par_info->origin.y * static_cast<size_t>(step_i) +
par_info->origin.x, step_i, img_i + lnbd.x,
par_info->is_hole ) > 0) ||
(!img0_i &&
icvTraceContour( img0 + par_info->origin.y * step +
icvTraceContour( img0 + par_info->origin.y * static_cast<size_t>(step) +
par_info->origin.x, step, img + lnbd.x,
par_info->is_hole ) > 0) )
break;