From nobody Sat Apr 11 12:44:14 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 8DE5F26CE05 for ; Fri, 10 Apr 2026 14:32:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775831528; cv=none; b=rDGoGNFKNttkWq0CUiaseM/HyoPQcCIm2iCi/PfipSG5HS3tUCRzVB70KX/+jbR40t18t24b1M56ev6KeWCyE9fEwbjU31ROYBn347ZR0up7H+7pFpIIZmtzwy0hzzxShK8gqgwyhPABfDuPYETybt6jzWurQgGe8JF0Weq7HKk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775831528; c=relaxed/simple; bh=0KN6SmaLsFq4+oTKOP3cZm1bwxb9wxqcqaeKJ7O9c84=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=R506ut/Ej/2yCh2Zmhr7maC8l3+BbMfnI/IGwTJvZpABXFIxNXjiyZZxYrByUcDfqwhU3W+hSweUz9QSwPtx/p7xpsoaCQPsvAD0v4pgBVi5e6lCdL1nbAmloGhO9N0djUhWCOsy2rhDdVo8kGWl7ZD668vjg2gWxyKrk10l+P4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=b1i5iSYZ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="b1i5iSYZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 078D6C4AF09; Fri, 10 Apr 2026 14:32:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1775831528; bh=0KN6SmaLsFq4+oTKOP3cZm1bwxb9wxqcqaeKJ7O9c84=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=b1i5iSYZxhaPxzcZeNVju0e4YSE770oebiRTIBwICUnCPrqZLJEmJZtSbZ8btRozA FA5zA+27z3XWxtciXqH1OQLxzK/ZHtuwTrz4hHc0CuNKiDqw7uVEDMR7B9PEOxy5nM D5nw9FWz3lg7oOWD146ibrY1MNdLiYGqagm5MgxzcpZDReM0/p5W/BJq7p4clVRNOL b8kqAkItdcW2/Vk6MfoSU9glGea/2mp8v03gFllGo4KkKeGiOvyEhCrNlRsEMHsQws O3wJpoOcllptStU5EpFnKlcVBajMEGC77EO3icD0bv/VuoinqUl8jcXlu6ZwKv0YMh C6Qhf6mK4X3DA== From: "Matthieu Baerts (NGI0)" Date: Fri, 10 Apr 2026 16:31:40 +0200 Subject: [PATCH mptcp-next v2 02/17] mptcp: pm: ADD_ADDR rtx: fix potential data-race Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260410-mptcp-inc-limits-v2-2-5402209f05d3@kernel.org> References: <20260410-mptcp-inc-limits-v2-0-5402209f05d3@kernel.org> In-Reply-To: <20260410-mptcp-inc-limits-v2-0-5402209f05d3@kernel.org> To: MPTCP Upstream Cc: "Matthieu Baerts (NGI0)" X-Mailer: b4 0.15.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=1178; i=matttbe@kernel.org; h=from:subject:message-id; bh=0KN6SmaLsFq4+oTKOP3cZm1bwxb9wxqcqaeKJ7O9c84=; b=owGbwMvMwCVWo/Th0Gd3rumMp9WSGDJvct68/1jhccYWy/0Z9/hX9Qtw8Ob5Gkx2dPv3PWPfs u7mGJmvHaUsDGJcDLJiiizSbZH5M59X8ZZ4+VnAzGFlAhnCwMUpABMxUGX4Xys279ZZwU3L/k3y ifybPfOpneT6900/pZOUD8/vu22xrZmRYcn2hTWTL6Y2vLYM98oRXFVddPfPzwzJrcJ+wTX6rcJ beQA= X-Developer-Key: i=matttbe@kernel.org; a=openpgp; fpr=E8CB85F76877057A6E27F77AF6B7824F4269A073 This mptcp_pm_add_timer() helper is executed as a timer callback in softirq context. To avoid any data races, the socket lock needs to be held with bh_lock_sock(). If the socket is in use, retry again soon after, similar to what is done with the keepalive timer. Fixes: 00cfd77b9063 ("mptcp: retransmit ADD_ADDR when timeout") Signed-off-by: Matthieu Baerts (NGI0) --- net/mptcp/pm.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c index 52f8f4eddfc2..989d87e2dc13 100644 --- a/net/mptcp/pm.c +++ b/net/mptcp/pm.c @@ -340,6 +340,13 @@ static void mptcp_pm_add_timer(struct timer_list *time= r) if (!entry->addr.id) return; =20 + bh_lock_sock(sk); + if (sock_owned_by_user(sk)) { + /* Try again later. */ + sk_reset_timer(sk, timer, jiffies + HZ / 20); + goto out; + } + if (mptcp_pm_should_add_signal_addr(msk)) { sk_reset_timer(sk, timer, jiffies + TCP_RTO_MAX / 8); goto out; @@ -368,6 +375,7 @@ static void mptcp_pm_add_timer(struct timer_list *timer) mptcp_pm_subflow_established(msk); =20 out: + bh_unlock_sock(sk); sock_put(sk); } =20 --=20 2.53.0