diff options
| author | Mark Johnston <markj@FreeBSD.org> | 2021-09-17 16:26:06 +0000 |
|---|---|---|
| committer | Mark Johnston <markj@FreeBSD.org> | 2021-09-24 13:01:51 +0000 |
| commit | e9e4f8092c2e0ccac922f930072cd14b22ee7c1c (patch) | |
| tree | 87c7592295523c71201c23cc4d9d4d6a442e2e6b | |
| parent | e68465ecbf7371efdab5a7d91838e33f4e5e177b (diff) | |
socket: Fix a use-after-free in soclose()
After releasing the fd reference to a socket "so", we should avoid
testing SOLISTENING(so) since the socket may have been freed. Instead,
directly test whether the list of unaccepted sockets is empty.
Fixes: f4bb1869ddd2 ("Consistently use the SOLISTENING() macro")
Pointy hat: markj
Sponsored by: The FreeBSD Foundation
(cherry picked from commit dfcef8771484271f2bccdb1dbc088a838441c5a7)
| -rw-r--r-- | sys/kern/uipc_socket.c | 24 |
1 files changed, 10 insertions, 14 deletions
diff --git a/sys/kern/uipc_socket.c b/sys/kern/uipc_socket.c index dc7407808535..13482fce5980 100644 --- a/sys/kern/uipc_socket.c +++ b/sys/kern/uipc_socket.c @@ -1176,6 +1176,7 @@ int soclose(struct socket *so) { struct accept_queue lqueue; + struct socket *sp, *tsp; int error = 0; KASSERT(!(so->so_state & SS_NOFDREF), ("soclose: SS_NOFDREF on enter")); @@ -1210,11 +1211,9 @@ drop: if (so->so_proto->pr_usrreqs->pru_close != NULL) (*so->so_proto->pr_usrreqs->pru_close)(so); + TAILQ_INIT(&lqueue); SOCK_LOCK(so); if (SOLISTENING(so)) { - struct socket *sp; - - TAILQ_INIT(&lqueue); TAILQ_SWAP(&lqueue, &so->sol_incomp, socket, so_list); TAILQ_CONCAT(&lqueue, &so->sol_comp, so_list); @@ -1232,17 +1231,14 @@ drop: KASSERT((so->so_state & SS_NOFDREF) == 0, ("soclose: NOFDREF")); so->so_state |= SS_NOFDREF; sorele(so); - if (SOLISTENING(so)) { - struct socket *sp, *tsp; - - TAILQ_FOREACH_SAFE(sp, &lqueue, so_list, tsp) { - SOCK_LOCK(sp); - if (sp->so_count == 0) { - SOCK_UNLOCK(sp); - soabort(sp); - } else - /* sp is now in sofree() */ - SOCK_UNLOCK(sp); + TAILQ_FOREACH_SAFE(sp, &lqueue, so_list, tsp) { + SOCK_LOCK(sp); + if (refcount_load(&sp->so_count) == 0) { + SOCK_UNLOCK(sp); + soabort(sp); + } else { + /* sp is now in sofree() */ + SOCK_UNLOCK(sp); } } CURVNET_RESTORE(); |