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Error: allocation-size-too-big

Address Sanitizer Error: allocation-size-too-big

This example shows the error found when an allocation is too large for the heap. Example sourced from LLVM compiler-rt test suite.

Example

// example1.cpp
// allocation-size-too-big error
#include <stdio.h>
#include <malloc.h>
#include <memory.h>

int x = 1000;
int y = 1000;

__declspec(noinline) void bad_function() {

  char* buffer = (char*)malloc(x * y * x * y); //Boom!

  memcpy(buffer, buffer + 8, 8); 
}

int main(int argc, char **argv) {
    bad_function();
    return 0;
}

To build and test this example, run these commands in a Visual Studio 2019 version 16.9 or later developer command prompt:

cl example1.cpp /fsanitize=address /Zi
devenv /debugexe example1.exe

Resulting error

Screenshot of debugger displaying allocation-size-too-big error in example 1.

See also

AddressSanitizer overview
AddressSanitizer known issues
AddressSanitizer build and language reference
AddressSanitizer runtime reference
AddressSanitizer shadow bytes
AddressSanitizer cloud or distributed testing
AddressSanitizer debugger integration
AddressSanitizer error examples