diff options
Diffstat (limited to 'net/ipv4/inet_fragment.c')
| -rw-r--r-- | net/ipv4/inet_fragment.c | 31 |
1 files changed, 15 insertions, 16 deletions
diff --git a/net/ipv4/inet_fragment.c b/net/ipv4/inet_fragment.c index d179a2c84222..19fae4811ab2 100644 --- a/net/ipv4/inet_fragment.c +++ b/net/ipv4/inet_fragment.c @@ -145,8 +145,7 @@ static void inet_frags_free_cb(void *ptr, void *arg) } spin_unlock_bh(&fq->lock); - if (refcount_sub_and_test(count, &fq->refcnt)) - inet_frag_destroy(fq); + inet_frag_putn(fq, count); } static LLIST_HEAD(fqdir_free_list); @@ -226,10 +225,10 @@ void fqdir_exit(struct fqdir *fqdir) } EXPORT_SYMBOL(fqdir_exit); -void inet_frag_kill(struct inet_frag_queue *fq) +void inet_frag_kill(struct inet_frag_queue *fq, int *refs) { if (del_timer(&fq->timer)) - refcount_dec(&fq->refcnt); + (*refs)++; if (!(fq->flags & INET_FRAG_COMPLETE)) { struct fqdir *fqdir = fq->fqdir; @@ -244,7 +243,7 @@ void inet_frag_kill(struct inet_frag_queue *fq) if (!READ_ONCE(fqdir->dead)) { rhashtable_remove_fast(&fqdir->rhashtable, &fq->node, fqdir->f->rhash_params); - refcount_dec(&fq->refcnt); + (*refs)++; } else { fq->flags |= INET_FRAG_HASH_DEAD; } @@ -328,7 +327,8 @@ static struct inet_frag_queue *inet_frag_alloc(struct fqdir *fqdir, timer_setup(&q->timer, f->frag_expire, 0); spin_lock_init(&q->lock); - refcount_set(&q->refcnt, 3); + /* One reference for the timer, one for the hash table. */ + refcount_set(&q->refcnt, 2); return q; } @@ -350,15 +350,20 @@ static struct inet_frag_queue *inet_frag_create(struct fqdir *fqdir, *prev = rhashtable_lookup_get_insert_key(&fqdir->rhashtable, &q->key, &q->node, f->rhash_params); if (*prev) { + /* We could not insert in the hash table, + * we need to cancel what inet_frag_alloc() + * anticipated. + */ + int refs = 1; + q->flags |= INET_FRAG_COMPLETE; - inet_frag_kill(q); - inet_frag_destroy(q); + inet_frag_kill(q, &refs); + inet_frag_putn(q, refs); return NULL; } return q; } -/* TODO : call from rcu_read_lock() and no longer use refcount_inc_not_zero() */ struct inet_frag_queue *inet_frag_find(struct fqdir *fqdir, void *key) { /* This pairs with WRITE_ONCE() in fqdir_pre_exit(). */ @@ -368,17 +373,11 @@ struct inet_frag_queue *inet_frag_find(struct fqdir *fqdir, void *key) if (!high_thresh || frag_mem_limit(fqdir) > high_thresh) return NULL; - rcu_read_lock(); - prev = rhashtable_lookup(&fqdir->rhashtable, key, fqdir->f->rhash_params); if (!prev) fq = inet_frag_create(fqdir, key, &prev); - if (!IS_ERR_OR_NULL(prev)) { + if (!IS_ERR_OR_NULL(prev)) fq = prev; - if (!refcount_inc_not_zero(&fq->refcnt)) - fq = NULL; - } - rcu_read_unlock(); return fq; } EXPORT_SYMBOL(inet_frag_find); |