From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 10FE8370AC8; Wed, 30 Sep 2026 16:04:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790784245; cv=none; b=ZM7jkQUX2a1A+W4eJVc7wCIojUmNtbFvW9gp0i9viNiX2OTWaYFfLbr2rlYbiHsIOnilywg7377yq5NPhGxe45o2pJHJ6Jgc81BDP12j4tLFfD2dUg6Iu4GRvR53O8Qdpozad4KbN3HEGHG60GqbMfSFhRSi9wePoDBr9vFykpM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790784245; c=relaxed/simple; bh=7u99MwLQR8gS4ptwBb7wxce06VkenGIuL5iNWEQWg4c=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=ZAlr30Y1sxH9uAjDRIIvfpDFtTUwci4T6RFMRPX9dHyjwRHeW7s/++imitGWdTy0iOzldHV4181IDRXau87nStAa+UnBNsTVk/mFDbSrKTHBTrI+Srykt+tlqpMjOkLJIPPOvRrmKpSXP4Jgln0zfmCQoxAlJBpdvJoX4ELKaaw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=iQaSA96w; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="iQaSA96w" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BC0D81F00898; Wed, 30 Sep 2026 16:04:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790784241; bh=6anL/MsVc4bpJ7Gu5eqMuYjGVU3TfUodk8e+WBMeVLQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=iQaSA96wPzh7E0fzGIClOb0nM/yqV+D0PJ0a5MCmayxYZAnZ//UndAEnDxyFGse8p H+fqI75WeY0Co4ty5jk8jAQk7JP50KzMDvCzUzr4y5RE035Z3ChvLcP7Y7zBRKZQFi z5zDbdyAgqijk3puWUKWRIzty2GyDwHSyplze2e4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot+fbf3648ae7f5bdb05c59@syzkaller.appspotmail.com, Jiayuan Chen , Allison Henderson , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.1 087/982] rds: annotate data-race around rs_seen_congestion Date: Wed, 30 Sep 2026 17:13:43 +0200 Message-ID: <20260930152418.677817625@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260930152416.775402466@linuxfoundation.org> References: <20260930152416.775402466@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jiayuan Chen [ Upstream commit 67636cab273ed0c0b0f2adab6c9369a471cb7966 ] rs_seen_congestion is read in rds_poll() and written in rds_sendmsg() and rds_poll() without any lock. Use READ_ONCE()/WRITE_ONCE() to annotate these lockless accesses and silence KCSAN. Reported-by: syzbot+fbf3648ae7f5bdb05c59@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/6a0f8d94.050a0220.6b33c.0000.GAE@google.com/ Signed-off-by: Jiayuan Chen Reviewed-by: Allison Henderson   Tested-by: Allison Henderson Link: https://patch.msgid.link/20260522011621.304470-1-jiayuan.chen@linux.dev Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/rds/af_rds.c | 4 ++-- net/rds/send.c | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/net/rds/af_rds.c b/net/rds/af_rds.c index a8004e8a78175..b166ac1f599e6 100644 --- a/net/rds/af_rds.c +++ b/net/rds/af_rds.c @@ -217,7 +217,7 @@ static __poll_t rds_poll(struct file *file, struct socket *sock, poll_wait(file, sk_sleep(sk), wait); - if (rs->rs_seen_congestion) + if (READ_ONCE(rs->rs_seen_congestion)) poll_wait(file, &rds_poll_waitq, wait); read_lock_irqsave(&rs->rs_recv_lock, flags); @@ -245,7 +245,7 @@ static __poll_t rds_poll(struct file *file, struct socket *sock, /* clear state any time we wake a seen-congested socket */ if (mask) - rs->rs_seen_congestion = 0; + WRITE_ONCE(rs->rs_seen_congestion, 0); return mask; } diff --git a/net/rds/send.c b/net/rds/send.c index 8aa06f7e4640c..2cedcb837b8f3 100644 --- a/net/rds/send.c +++ b/net/rds/send.c @@ -1340,7 +1340,7 @@ int rds_sendmsg(struct socket *sock, struct msghdr *msg, size_t payload_len) ret = rds_cong_wait(conn->c_fcong, dport, nonblock, rs); if (ret) { - rs->rs_seen_congestion = 1; + WRITE_ONCE(rs->rs_seen_congestion, 1); goto out; } while (!rds_send_queue_rm(rs, conn, cpath, rm, rs->rs_bound_port, -- 2.53.0