linux-kernel - Re: [PATCH] x86/microcode: Change checksum to u32

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Message-ID: <20160316105226.GB21259@amd>
Date:	Wed, 16 Mar 2016 11:52:26 +0100
From:	Pavel Machek <pavel@....cz>
To:	Chris Bainbridge <chris.bainbridge@...il.com>
Cc:	bp@...en8.de, x86@...nel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] x86/microcode: Change checksum to u32

Hi!

> Checksum should be unsigned 32-bit otherwise the calculation overflows
> resulting in undefined behaviour:

> @@ -49,7 +49,7 @@ int microcode_sanity_check(void *mc, int print_err)
>  	unsigned long total_size, data_size, ext_table_size;
>  	struct microcode_header_intel *mc_header = mc;
>  	struct extended_sigtable *ext_header = NULL;
> -	int sum, orig_sum, ext_sigcount = 0, i;
> +	u32 sum, orig_sum, ext_sigcount = 0, i;

Ok, but what about i and ext_sigcount?
									Pavel

-- 
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