This is a note to let you know that I've just added the patch titled net/smc: avoid overwriting when adjusting sock bufsizes to the 6.6-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-smc-avoid-overwriting-when-adjusting-sock-bufsiz.patch and it can be found in the queue-6.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 0f974c14b66ae11bfb9233c96d99c2d3d455c37a Author: Wen Gu <guwen@xxxxxxxxxxxxxxxxx> Date: Fri May 31 16:54:17 2024 +0800 net/smc: avoid overwriting when adjusting sock bufsizes [ Upstream commit fb0aa0781a5f457e3864da68af52c3b1f4f7fd8f ] When copying smc settings to clcsock, avoid setting clcsock's sk_sndbuf to sysctl_tcp_wmem[1], since this may overwrite the value set by tcp_sndbuf_expand() in TCP connection establishment. And the other setting sk_{snd|rcv}buf to sysctl value in smc_adjust_sock_bufsizes() can also be omitted since the initialization of smc sock and clcsock has set sk_{snd|rcv}buf to smc.sysctl_{w|r}mem or ipv4_sysctl_tcp_{w|r}mem[1]. Fixes: 30c3c4a4497c ("net/smc: Use correct buffer sizes when switching between TCP and SMC") Link: https://lore.kernel.org/r/5eaf3858-e7fd-4db8-83e8-3d7a3e0e9ae2@xxxxxxxxxxxxxxxxx Signed-off-by: Wen Gu <guwen@xxxxxxxxxxxxxxxxx> Reviewed-by: Wenjia Zhang <wenjia@xxxxxxxxxxxxx> Reviewed-by: Gerd Bayer <gbayer@xxxxxxxxxxxxx>, too. Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index ef5b5d498ef3e..3158b94fd347a 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -460,29 +460,11 @@ static int smc_bind(struct socket *sock, struct sockaddr *uaddr, static void smc_adjust_sock_bufsizes(struct sock *nsk, struct sock *osk, unsigned long mask) { - struct net *nnet = sock_net(nsk); - nsk->sk_userlocks = osk->sk_userlocks; - if (osk->sk_userlocks & SOCK_SNDBUF_LOCK) { + if (osk->sk_userlocks & SOCK_SNDBUF_LOCK) nsk->sk_sndbuf = osk->sk_sndbuf; - } else { - if (mask == SK_FLAGS_SMC_TO_CLC) - WRITE_ONCE(nsk->sk_sndbuf, - READ_ONCE(nnet->ipv4.sysctl_tcp_wmem[1])); - else - WRITE_ONCE(nsk->sk_sndbuf, - 2 * READ_ONCE(nnet->smc.sysctl_wmem)); - } - if (osk->sk_userlocks & SOCK_RCVBUF_LOCK) { + if (osk->sk_userlocks & SOCK_RCVBUF_LOCK) nsk->sk_rcvbuf = osk->sk_rcvbuf; - } else { - if (mask == SK_FLAGS_SMC_TO_CLC) - WRITE_ONCE(nsk->sk_rcvbuf, - READ_ONCE(nnet->ipv4.sysctl_tcp_rmem[1])); - else - WRITE_ONCE(nsk->sk_rcvbuf, - 2 * READ_ONCE(nnet->smc.sysctl_rmem)); - } } static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk,