Re: [patch] netfilter: prevent harmless integer overflow

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Tue, Jun 18, 2013 at 10:46:03AM +0300, Dan Carpenter wrote:
> This overflow is harmless because a few lines later we check:
> 
> 	if (num_counters != t->private->nentries) {
> 
> But it still upsets the static checkers.
> 
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> 
> diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
> index 3d110c4..141350e 100644
> --- a/net/bridge/netfilter/ebtables.c
> +++ b/net/bridge/netfilter/ebtables.c
> @@ -1278,6 +1278,8 @@ static int do_update_counters(struct net *net, const char *name,
>  
>  	if (num_counters == 0)
>  		return -EINVAL;
> +	if (num_counters > INT_MAX / sizeof(*tmp))
> +		return -ENOMEM;

This is artificially limiting to INT_MAX / sizeof(struct counters).
Before this patch, the limit is UINT_MAX / sizeof(struct counters). I
think it's very unlikely to hit such a limit though, but as you
mentioned we cover the overflow already. Adding it to calm down a
static checker sound a bit too much for me.
--
To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Kernel Development]     [Kernel Announce]     [Kernel Newbies]     [Linux Networking Development]     [Share Photos]     [IDE]     [Security]     [Git]     [Netfilter]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Device Mapper]

  Powered by Linux