From: Eric Dumazet <eduma...@google.com>
Date: Wed, 7 Nov 2018 22:10:53 -0800
> @@ -204,22 +205,22 @@ static struct inet_frag_queue *inet_frag_create(struct
> netns_frags *nf,
> /* TODO : call from rcu_read_lock() and no longer use
> refcount_inc_not_zero() */
> struct inet_frag_queue *inet_frag_find(struct netns_frags *nf, void *key)
> {
> - struct inet_frag_queue *fq;
> + struct inet_frag_queue *fq, *prev;
>
> if (!nf->high_thresh || frag_mem_limit(nf) > nf->high_thresh)
> return NULL;
>
> rcu_read_lock();
>
> - fq = rhashtable_lookup(&nf->rhashtable, key, nf->f->rhash_params);
> - if (fq) {
> + prev = rhashtable_lookup(&nf->rhashtable, key, nf->f->rhash_params);
> + if (!prev)
> + fq = inet_frag_create(nf, key, &prev);
> + if (prev && !IS_ERR(prev)) {
> + fq = prev;
> if (!refcount_inc_not_zero(&fq->refcnt))
> fq = NULL;
> - rcu_read_unlock();
> - return fq;
> }
> rcu_read_unlock();
> -
> - return inet_frag_create(nf, key);
> + return fq;
GCC is unwilling to see that all paths leading to that final return
statement do in fact set 'fq' one way or another:
net/ipv4/inet_fragment.c: In function ‘inet_frag_find’:
net/ipv4/inet_fragment.c:224:9: warning: ‘fq’ may be used uninitialized in this
function [-Wmaybe-uninitialized]
This is with:
gcc (GCC) 8.2.1 20181011 (Red Hat 8.2.1-4)
Please adjust your patch so that the warning is eliminated.
Thanks.
