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From: Markus Armbruster <armbru@redhat.com>
Subject: Re: [Qemu-devel] [PATCH] linux-user: Fix possible realloc memory leak
References: <1295296566-30287-1-git-send-email-weil@mail.berlios.de>
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Date: Tue, 18 Jan 2011 18:51:00 +0100
In-Reply-To: <4D35C960.6040703@mail.berlios.de> (Stefan Weil's message of
	"Tue, 18 Jan 2011 18:09:52 +0100")
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To: Stefan Weil <weil@mail.berlios.de>
Cc: Riku Voipio <riku.voipio@iki.fi>, QEMU Developers <qemu-devel@nongnu.org>

Stefan Weil <weil@mail.berlios.de> writes:

> Am 18.01.2011 09:26, schrieb Markus Armbruster:
>> Stefan Weil <weil@mail.berlios.de> writes:
>>
>>> Extract from "man realloc":
>>> "If realloc() fails the original block is left untouched;
>>> it is not freed or moved."
>>>
>>> Fix a possible memory leak (reported by cppcheck).
>>>
>>> Cc: Riku Voipio <riku.voipio@iki.fi>
>>> Signed-off-by: Stefan Weil <weil@mail.berlios.de>
>>
>> Sidestep the problem via qemu_realloc() instead?
>
> The same change was applied to bsd-user/elfload.c.
>
> As symbol loading is not essential in most applications,
> returning after out-of-memory should be better than
> aborting (that's what qemu_realloc does).

Unless the requested size is *really* large, I'd expect this to stave
off the out-of-memory failure for a few microseconds at best.