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 6C5F2DDC5; Thu, 28 May 2026 20:27:17 +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=1780000038; cv=none; b=XykF1FAN78poRO04Lf/JU6EsowsrUJyxn66Ur3qC3HT9ZJLrhx5oHIfs/X6TutJ+2Kj5xJ6x8hkgAnzTorlzhFVLjgo+mNypJo1adFjc4IjKbW7fo9WLZZTH0kXBQNhMaelZzZHx0H6YxOwIhr0cqMeHWZ9OS2igS8tia6pd9Rc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780000038; c=relaxed/simple; bh=qBumcJqSkj3vqfNxb41qNI+TejzYzEoGH66UzfSY/VU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=g24QSnxSGOPtfNtuay6ODxjH40IZmw3Geq4qJC3Vgvl3A3uUJKMrFBxefICGYC3KT97QI5umRVFDNP9tgnm1Z0gr/CTQGeAu0hrOsW//3VFlfEesDx6L/KqcJt3961TtmT65e00uny6/5/UpNNsyr6FNEQh74RiY1dsk6SjJ3cA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=C7BkS/uy; 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="C7BkS/uy" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CB4E21F000E9; Thu, 28 May 2026 20:27:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1780000037; bh=/r3sNyl9ZZJ04FAzVcAkHBxYW/16Y4jEFB80Kszkgfs=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=C7BkS/uycMXLTA9rRZSVSlg95JG8zxfo1oF42YKcXDQkIWatvCN7qIM0EDZ69vW5w NsraqVULBrwIampNbWTgSGimbFdO/2bhoUF66dNs5gkxubSn3mMqYG3IctTwIEIjr1 jNBs9HJzCRDuw76iYxbAkbOZYOFgayRz1e7jO3rk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?=E9=92=B1=E4=B8=80=E9=93=AD?= , Jakub Kicinski , Sabrina Dubroca , Paolo Abeni , Sasha Levin Subject: [PATCH 6.18 281/377] net: tls: fix off-by-one in sg_chain entry count for wrapped sk_msg ring Date: Thu, 28 May 2026 21:48:39 +0200 Message-ID: <20260528194646.491094613@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260528194638.371537336@linuxfoundation.org> References: <20260528194638.371537336@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jakub Kicinski [ Upstream commit 285943c6e7ca309bbea84b253745154241d9788a ] When an sk_msg scatterlist ring wraps (sg.end < sg.start), tls_push_record() chains the tail portion of the ring to the head using sg_chain(). An extra entry in the sg array is reserved for this: struct sk_msg_sg { [...] /* The extra two elements: * 1) used for chaining the front and sections when the list becomes * partitioned (e.g. end < start). The crypto APIs require the * chaining; * 2) to chain tailer SG entries after the message. */ struct scatterlist data[MAX_MSG_FRAGS + 2]; The current code uses MAX_SKB_FRAGS + 1 as the ring size: sg_chain(&msg_pl->sg.data[msg_pl->sg.start], MAX_SKB_FRAGS - msg_pl->sg.start + 1, msg_pl->sg.data); This places the chain pointer at sg_chain(data[start], (MAX_SKB_FRAGS - msg_start + 1) .. = &data[start] + (MAX_SKB_FRAGS - msg_start + 1) - 1 = data[start + (MAX_SKB_FRAGS - start + 1) - 1] = data[MAX_SKB_FRAGS] instead of the true last entry. This is likely due to a "race" of the commit under Fixes landing close to commit 031097d9e079 ("bpf: sk_msg, zap ingress queue on psock down") Convert to ARRAY_SIZE and drop the data[start] / - start (as suggested by Sabrina). Reported-by: 钱一铭 Fixes: 9aaaa56845a0 ("bpf: Sockmap/tls, skmsg can have wrapped skmsg that needs extra chaining") Signed-off-by: Jakub Kicinski Reviewed-by: Sabrina Dubroca Link: https://patch.msgid.link/20260511174920.433155-2-kuba@kernel.org Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- net/tls/tls_sw.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index f2ea190777f0b..1ad5d0e7ae27f 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -800,11 +800,9 @@ static int tls_push_record(struct sock *sk, int flags, sg_mark_end(sk_msg_elem(msg_pl, i)); } - if (msg_pl->sg.end < msg_pl->sg.start) { - sg_chain(&msg_pl->sg.data[msg_pl->sg.start], - MAX_SKB_FRAGS - msg_pl->sg.start + 1, + if (msg_pl->sg.end < msg_pl->sg.start) + sg_chain(msg_pl->sg.data, ARRAY_SIZE(msg_pl->sg.data), msg_pl->sg.data); - } i = msg_pl->sg.start; sg_chain(rec->sg_aead_in, 2, &msg_pl->sg.data[i]); -- 2.53.0