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Date: Thu, 21 Jun 2018 18:18:56 -0500
From: Segher Boessenkool <segher@kernel.crashing.org>
To: Breno Leitao <leitao@debian.org>
Cc: linuxppc-dev@lists.ozlabs.org,
 Anshuman Khandual <khandual@linux.vnet.ibm.com>
Subject: Re: [PATCH] selftests/powerpc: Fix strncpy usage
Message-ID: <20180621231856.GO16221@gate.crashing.org>
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On Wed, Jun 20, 2018 at 07:51:11PM -0300, Breno Leitao wrote:
> -	strncpy(prog, argv[0], strlen(argv[0]));
> +	strncpy(prog, argv[0], sizeof(prog) - 1);

	strncpy(prog, argv[0], sizeof prog);
	if (prog[sizeof prog - 1])
		scream_bloody_murder();

Silently using the wrong data is a worse habit than not checking for
overflows ;-)


Segher