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Syscall param write(buf) contains uninitialised or unaddressable byte(s)
write() ¶àдÁË one byte
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int main()
{
        char buf[80];

        strcpy(buf, "abcdef");
        write(1, buf, 8);
        return 0;
}


Conditional jump or move depends on uninitialised value(s)
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int main()
{
        int i;

        if ( i == 3 )
                printf("ok\n");
        else
                printf("fail\n");
        return 0;
}


==17774== Syscall param write(buf) contains uninitialised or unaddressable byte(s)
==17774==    at 0x3C0FA32F: (within /lib/libc.so.6)
==17774==    by 0x8048475: _start (in /home/kasicass/sandbox/valgrind/a.out)
==17774==    by 0x0: ???
==17774==  Address 0x3C122026 is 2 bytes inside a block of size 10 alloc'd
==17774==    at 0x3C038183: malloc (in /usr/local/lib/valgrind/vgpreload_memcheck.so)
==17774==    by 0x8048551: main (test.c:6)
¸ø write() µÄ p ÖУ¬Ö»ÓÐ 2byte valid¡£
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int main()
{
        char *p = malloc(10);
        p[0] = 'a';
        p[1] = 'b';
        write(1, p, 10);
        return 0;
}