From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephan Brauss <sbrauss@optronic.ch>
Subject: A rather special bug?
Date: Tue, 25 Mar 2003 07:56:16 +0100
Sender: linux-msdos-owner@vger.kernel.org
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Hello!

I think that I have found a bug that is present at least in dosemu-1.0.2.
Compile the appended program, run it and press any key while
the memory testing loop is running. You will see that one byte of the
allocated memory blocks is altered and now contains the ascii code of 
the pressed character. Can someone reproduce this problem? Is it fixed
in newer dosemu versions?

Stephan

----------------------

#include <stdio.h>
#include <stdlib.h>

#define SEGMENTS 7
#define SIZE 65500

int *segments[SEGMENTS];

int main()
{
	int i,j,k;

	for(i=0;i<SEGMENTS;i++)
	{
		printf("malloc segment %d\n",i+1);
		segments[i]=(int *)malloc(SIZE);
		if(segments[i]==NULL)
		{
			printf("malloc error\n");
			exit(1);
		}
		for(j=0;j<SIZE/sizeof(int);j++)
			segments[i][j]=0;
	}

	k=1;
	for(;;)
	{
		printf("loop: %d\n",k);
		for(i=0;i<SEGMENTS;i++)
		{
			for(j=0;j<SIZE/sizeof(int);j++)
			{
				if(segments[i][j]!=0)
				{
					printf("segments[%d][%d]=%d\n",i,j,segments[i][j]);
				}
			}
		}
		k++;
	}
	return 0;
}