Re: [PATCH net-next] net: tipc: avoid possible garbage value

From: Justin Stitt
Date: Thu Sep 12 2024 - 17:39:17 EST


Hi,

On Thu, Sep 12, 2024 at 4:01 AM Su Hui <suhui@xxxxxxxxxxxx> wrote:
>
> Clang static checker (scan-build) warning:
> net/tipc/bcast.c:305:4:
> The expression is an uninitialized value. The computed value will also
> be garbage [core.uninitialized.Assign]
> 305 | (*cong_link_cnt)++;
> | ^~~~~~~~~~~~~~~~~~
>
> tipc_rcast_xmit() will increase cong_link_cnt's value, but cong_link_cnt
> is uninitialized. Although it won't really cause a problem, it's better
> to fix it.

Agreed.

Reviewed-by: Justin Stitt <justinstitt@xxxxxxxxxx>
>
> Fixes: dca4a17d24ee ("tipc: fix potential hanging after b/rcast changing")
> Signed-off-by: Su Hui <suhui@xxxxxxxxxxxx>
> ---
> net/tipc/bcast.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/net/tipc/bcast.c b/net/tipc/bcast.c
> index 593846d25214..a3699be6a634 100644
> --- a/net/tipc/bcast.c
> +++ b/net/tipc/bcast.c
> @@ -321,7 +321,7 @@ static int tipc_mcast_send_sync(struct net *net, struct sk_buff *skb,
> struct tipc_msg *hdr, *_hdr;
> struct sk_buff_head tmpq;
> struct sk_buff *_skb;
> - u16 cong_link_cnt;
> + u16 cong_link_cnt = 0;
> int rc = 0;
>
> /* Is a cluster supporting with new capabilities ? */
> --
> 2.30.2
>

Thanks
Justin