netdev - [PATCH net-next 01/27] sock: deduplicate ->sk_wmem

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Sun,  3 Apr 2022 14:06:13 +0100
From:   Pavel Begunkov <asml.silence@...il.com>
To:     netdev@...r.kernel.org, "David S . Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>
Cc:     Eric Dumazet <edumazet@...gle.com>, Wei Liu <wei.liu@...nel.org>,
        Paul Durrant <paul@....org>,
        Pavel Begunkov <asml.silence@...il.com>
Subject: [PATCH net-next 01/27] sock: deduplicate ->sk_wmem_alloc check

The main ->sk_wmem_alloc check in sock_def_write_space() almost
completely repeats sock_writeable() apart from small differences like
rounding, so we should be able to replace the first check and remove
extra sock_writeable().

Signed-off-by: Pavel Begunkov <asml.silence@...il.com>
---
 net/core/sock.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/net/core/sock.c b/net/core/sock.c
index 1180a0cb0110..f5766d6e27cb 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -3174,15 +3174,14 @@ static void sock_def_write_space(struct sock *sk)
 	/* Do not wake up a writer until he can make "significant"
 	 * progress.  --DaveM
 	 */
-	if ((refcount_read(&sk->sk_wmem_alloc) << 1) <= READ_ONCE(sk->sk_sndbuf)) {
+	if (sock_writeable(sk)) {
 		wq = rcu_dereference(sk->sk_wq);
 		if (skwq_has_sleeper(wq))
 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
 						EPOLLWRNORM | EPOLLWRBAND);
 
 		/* Should agree with poll, otherwise some programs break */
-		if (sock_writeable(sk))
-			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
+		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
 	}
 
 	rcu_read_unlock();
-- 
2.35.1