tls: fix lockless read of strp->msg_ready in ->poll
tls_sk_poll is called without locking the socket, and needs to read
strp->msg_ready (via tls_strp_msg_ready). Convert msg_ready to a bool
and use READ_ONCE/WRITE_ONCE where needed. The remaining reads are
only performed when the socket is locked.
Fixes: 121dca784fc0 ("tls: suppress wakeups unless we have a full record")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://lore.kernel.org/r/0b7ee062319037cf86af6b317b3d72f7bfcd2e97.1713797701.git.sd@queasysnail.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
diff --git a/net/tls/tls_strp.c b/net/tls/tls_strp.c
index ca1e0e1..5df08d8 100644
--- a/net/tls/tls_strp.c
+++ b/net/tls/tls_strp.c
@@ -360,7 +360,7 @@ static int tls_strp_copyin(read_descriptor_t *desc, struct sk_buff *in_skb,
if (strp->stm.full_len && strp->stm.full_len == skb->len) {
desc->count = 0;
- strp->msg_ready = 1;
+ WRITE_ONCE(strp->msg_ready, 1);
tls_rx_msg_ready(strp);
}
@@ -528,7 +528,7 @@ static int tls_strp_read_sock(struct tls_strparser *strp)
if (!tls_strp_check_queue_ok(strp))
return tls_strp_read_copy(strp, false);
- strp->msg_ready = 1;
+ WRITE_ONCE(strp->msg_ready, 1);
tls_rx_msg_ready(strp);
return 0;
@@ -580,7 +580,7 @@ void tls_strp_msg_done(struct tls_strparser *strp)
else
tls_strp_flush_anchor_copy(strp);
- strp->msg_ready = 0;
+ WRITE_ONCE(strp->msg_ready, 0);
memset(&strp->stm, 0, sizeof(strp->stm));
tls_strp_check_rcv(strp);
