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#include <string.h>
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#include <stdio.h>
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#include <stdlib.h>
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/*
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I used as environment the virtual machine provided here
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http://www.cis.upenn.edu/~cis551/box.tar
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This is Debian/Etch with Linux 2.6.18 with gcc 4.1.2 from 2008.
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Some installation notes for this virtual machine under VMWare
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are here
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http://www.cis.upenn.edu/~cis551/project1.pdf
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I run the virtial machine under MacOSX using the program
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VirtualBox available for free from
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https://www.virtualbox.org
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The C-program I compiled the program with
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gcc -ggdb -fno-stack-protector -mpreferred-stack-boundary=2
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*/
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void foo (char *bar)
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{
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float my_float = 10.5; // in hex: \x41\x28\x00\x00
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char buffer[28];
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printf("my float value = %f\n", my_float);
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strcpy(buffer, bar);
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printf("my float value = %f\n", my_float);
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}
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int main (int argc, char **argv)
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{
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foo("my string is too long !!!!! "); \\ all is normal
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foo("my string is too long !!!!! \x10\x10\xc0\x42"); \\ overwrites my_float
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return 0;
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}
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