net: Fix potential memory leak in proto_register()

If we failed to assign proto idx, we free the twsk_slab_name but forget to
free the twsk_slab. Add a helper function tw_prot_cleanup() to free these
together and also use this helper function in proto_unregister().

Fixes: b45ce32135 ("sock: fix potential memory leak in proto_register()")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Miaohe Lin 2020-08-10 08:16:58 -04:00 committed by David S. Miller
parent 50caa777a3
commit 0f5907af39

View File

@ -3406,6 +3406,16 @@ static void sock_inuse_add(struct net *net, int val)
}
#endif
static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
{
if (!twsk_prot)
return;
kfree(twsk_prot->twsk_slab_name);
twsk_prot->twsk_slab_name = NULL;
kmem_cache_destroy(twsk_prot->twsk_slab);
twsk_prot->twsk_slab = NULL;
}
static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
{
if (!rsk_prot)
@ -3476,7 +3486,7 @@ int proto_register(struct proto *prot, int alloc_slab)
prot->slab_flags,
NULL);
if (prot->twsk_prot->twsk_slab == NULL)
goto out_free_timewait_sock_slab_name;
goto out_free_timewait_sock_slab;
}
}
@ -3484,15 +3494,15 @@ int proto_register(struct proto *prot, int alloc_slab)
ret = assign_proto_idx(prot);
if (ret) {
mutex_unlock(&proto_list_mutex);
goto out_free_timewait_sock_slab_name;
goto out_free_timewait_sock_slab;
}
list_add(&prot->node, &proto_list);
mutex_unlock(&proto_list_mutex);
return ret;
out_free_timewait_sock_slab_name:
out_free_timewait_sock_slab:
if (alloc_slab && prot->twsk_prot)
kfree(prot->twsk_prot->twsk_slab_name);
tw_prot_cleanup(prot->twsk_prot);
out_free_request_sock_slab:
if (alloc_slab) {
req_prot_cleanup(prot->rsk_prot);
@ -3516,12 +3526,7 @@ void proto_unregister(struct proto *prot)
prot->slab = NULL;
req_prot_cleanup(prot->rsk_prot);
if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
kmem_cache_destroy(prot->twsk_prot->twsk_slab);
kfree(prot->twsk_prot->twsk_slab_name);
prot->twsk_prot->twsk_slab = NULL;
}
tw_prot_cleanup(prot->twsk_prot);
}
EXPORT_SYMBOL(proto_unregister);