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Bug#402694: marked as done (new[] operator can silently allocate less than requested)

Your message dated Wed, 16 Nov 2016 12:07:05 +0100
with message-id <1d7b3668-762a-58fd-b185-137feb519adf@debian.org>
and subject line Re: new[] operator can silently allocate less than requested
has caused the Debian Bug report #402694,
regarding new[] operator can silently allocate less than requested
to be marked as done.

This means that you claim that the problem has been dealt with.
If this is not the case it is now your responsibility to reopen the
Bug report if necessary, and/or fix the problem forthwith.

(NB: If you are a system administrator and have no idea what this
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immediately.)


-- 
402694: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=402694
Debian Bug Tracking System
Contact owner@bugs.debian.org with problems
--- Begin Message --- 
Package: libstdc++6
Version: 4.1.1-21
Severity: important
Tags: security

See bug #155529 -- this is the same problem referenced by the same
advisory:  http://cert.uni-stuttgart.de/advisories/calloc.php
Severity should probably be higher for a security problem, but I'll
set it the same as that original bug.

Basically 
   Big *big = new Big[size]
can allocate less than requested but fail to throw an exception, if
   sizeof(Big) * size
overflows.  

A sample program is attached.  On i386, the first allocation correctly
succeeds, the second correctly throws an exception (it's trying to
allocate ~4GB), and the third appears to allocate successfully but
segfaults on access.

-- System Information:
Debian Release: testing/unstable
  APT prefers testing
  APT policy: (990, 'testing'), (500, 'unstable'), (1, 'experimental')
Architecture: i386 (i686)
Shell:  /bin/sh linked to /bin/bash
Kernel: Linux 2.6.17.4
Locale: LANG=POSIX, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)

Versions of packages libstdc++6 depends on:
ii  gcc-4.1-base                  4.1.1-21   The GNU Compiler Collection (base 
ii  libc6                         2.3.6-15   GNU C Library: Shared libraries
ii  libgcc1                       1:4.1.1-21 GCC support library

libstdc++6 recommends no packages.

-- no debconf information

#include <stdio.h>
#include <exception>

class Big {
public:
	char big[1000];
};

int main()
{
	int size[3] = { 4294, 4294000, 4296000 };

	for (int i=0; i<3; i++) {
		try {
			Big *bigs = new Big[size[i]];
			printf("%d allocated\n", i);
			bigs[1234].big[0] = 0;
			printf("%d tested\n", i);
			delete[] bigs;
		} catch(std::exception e) {
			printf("%d exception\n", i);
		}
	}
}

--- End Message ---
--- Begin Message --- 
Version: 4.8.4-1

fixed in gcc-4.8 4.8.4-1.

--- End Message ---
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