Michal Luczaj wrote:
Consider a sockmap entry being updated with the same socket:
osk = stab->sks[idx]; sock_map_add_link(psock, link, map, &stab->sks[idx]); stab->sks[idx] = sk; if (osk) sock_map_unref(osk, &stab->sks[idx]);
Due to sock_map_unref(), which invokes sock_map_del_link(), all the psock's links for stab->sks[idx] are torn:
list_for_each_entry_safe(link, tmp, &psock->link, list) { if (link->link_raw == link_raw) { ... list_del(&link->list); sk_psock_free_link(link); } }
And that includes the new link sock_map_add_link() added just before the unref.
This results in a sockmap holding a socket, but without the respective link. This in turn means that close(sock) won't trigger the cleanup, i.e. a closed socket will not be automatically removed from the sockmap.
Stop tearing the links when a matching link_raw is found.
Signed-off-by: Michal Luczaj mhal@rbox.co
Thanks. LGTM.
Reviewed-by: John Fastabend john.fastabend@gmail.com
net/core/sock_map.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/net/core/sock_map.c b/net/core/sock_map.c index 78347d7d25ef31525f8ec0a755a18e5793ad92c0..20b348b1964a10a1b0bfbe1a90a4a4cd99715b81 100644 --- a/net/core/sock_map.c +++ b/net/core/sock_map.c @@ -159,6 +159,7 @@ static void sock_map_del_link(struct sock *sk, verdict_stop = true; list_del(&link->list); sk_psock_free_link(link);
break;-- 2.46.2