Reply-To: xlpang@redhat.com
Subject: Re: [patch] kexec: potetially using uninitialized variable
References: <20160311080747.GA31887@mwanda>
To: Dan Carpenter <dan.carpenter@oracle.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Vivek Goyal <vgoyal@redhat.com>
Cc: Dave Young <dyoung@redhat.com>, Xunlei Pang <xlpang@redhat.com>,
        Ingo Molnar <mingo@kernel.org>, Toshi Kani <toshi.kani@hpe.com>,
        Mimi Zohar <zohar@linux.vnet.ibm.com>,
        Minfei Huang <mnfhuang@gmail.com>, linux-kernel@vger.kernel.org,
        kernel-janitors@vger.kernel.org
From: Xunlei Pang <xpang@redhat.com>
Message-ID: <56E2875B.8010909@redhat.com>
Date: Fri, 11 Mar 2016 16:52:43 +0800
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Hi Dan,

On 2016/03/11 at 16:07, Dan Carpenter wrote:
> At the end of the function we check if "ret" has a negative error code,
> but it seems possible that it is uninitialized.
>
> Fixes: 12db5562e035 ('kexec: load and relocate purgatory at kernel load time')
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
>
> diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
> index 503bc2d..63d1af3 100644
> --- a/kernel/kexec_file.c
> +++ b/kernel/kexec_file.c
> @@ -795,7 +795,7 @@ out:
>  
>  static int kexec_apply_relocations(struct kimage *image)
>  {
> -	int i, ret;
> +	int i, ret = 0;
>  	struct purgatory_info *pi = &image->purgatory_info;
>  	Elf_Shdr *sechdrs = pi->sechdrs;
>  

Look further, there is a condition at the beginning of the for loop:
 

        if (sechdrs[i].sh_type != SHT_RELA &&
            sechdrs[i].sh_type != SHT_REL)
            continue;

So, I think that's ok, but I don't konw if GCC is smart enough not to throw warnings.

Regards,
Xunlei