From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ferruh Yigit <ferruh.yigit@intel.com>
Subject: Re: [PATCH] drivers: fix to replace strcat with strncat
Date: Mon, 14 Jan 2019 13:29:38 +0000
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To: Chaitanya Babu Talluri <tallurix.chaitanya.babu@intel.com>, dev@dpdk.org,
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On 1/14/2019 6:04 AM, Chaitanya Babu Talluri wrote:
> Strcat does not check the destination length and there might be
> chances of string overflow so insted of strcat, strncat is used.
> 
> Fixes: 540a211084 ("bnx2x: driver core")
> Fixes: e163c18a15 ("net/i40e: update ptype and pctype info")
> Fixes: ef28aa96e5 ("net/nfp: support multiprocess")
> Fixes: 6f4eec2565 ("test/crypto: enhance scheduler unit tests")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Chaitanya Babu Talluri <tallurix.chaitanya.babu@intel.com>

<...>

> @@ -685,11 +687,11 @@ nfp_acquire_secondary_process_lock(struct nfp_pcie_user *desc)
>  	 * driver is used because that implies root user.
>  	 */
>  	home_path = getenv("HOME");
> -	lockfile = calloc(strlen(home_path) + strlen(lockname) + 1,
> +	lockfile = calloc(LOCKFILE_HOME_PATH + strlen(lockname) + 1,
>  			  sizeof(char));
>  
> -	strcat(lockfile, home_path);
> -	strcat(lockfile, "/.lock_nfp_secondary");
> +	strncat(lockfile, home_path, LOCKFILE_HOME_PATH);
> +	strncat(lockfile, lockname, strlen(lockfile));

I guess this need to be 'LOCKFILE_HOME_PATH - strlen(lockfile) - 1' instead.
But also this can be implemented as 'snprintf()'

Since 'lockfile' allocated dynamically based on sizes of existing strings, using
'lockname' instead of "/.lock_nfp_secondary" will show that there won't be any
overflow but tools still may be complaining about 'strcat' usage.