net: convert sock.sk_wmem_alloc from atomic_t to refcount_t

refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 1 deletions

diff --git a/net/rds/tcp_send.c b/net/rds/tcp_send.c
index 52d11d7725c8..0d8616aa5bad 100644
--- a/net/rds/tcp_send.c
+++ b/net/rds/tcp_send.c
@@ -202,7 +202,7 @@ void rds_tcp_write_space(struct sock *sk)
         tc->t_last_seen_una = rds_tcp_snd_una(tc);
         rds_send_path_drop_acked(cp, rds_tcp_snd_una(tc), rds_tcp_is_acked);
 
-        if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf)
+        if ((refcount_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf)
                 queue_delayed_work(rds_wq, &cp->cp_send_w, 0);
 
 out: