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 3F77A52CCF4 for ; Tue, 29 Sep 2026 14:12:52 +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=1790691173; cv=none; b=st0oknnZuJgKTFURmgvbJTT1LDRyJqkswsg8aAX7MgzNTkUZVNsZWZiF2Rmp10S7ccMa4rhwjJKc/54yiqgo1yawE9eOVtZquCBUd56DUT8Q0XaVNVGzuK9g6VJ1QLfRjfE13xbjJBGzLKpycU3BSFMaGQ3xhh5gOVypzLFmnps= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790691173; c=relaxed/simple; bh=y5CKzn/ede0YjkqijGd0ecd4375ljsQEVQyPDOkSHdk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=G2gRGquT2WoJr3o9CEPzHw1faosg84HRuvR5iu0zvB8hPTXKywdB3kVb5rRGYEH2cWXdCIUAXscR3Th58IdIOWe6S/AOY5DsCfAUGqF4TTBc8TFWkbN+Ueios2dyL41MkK9qQa/QocHrABPsJOBQVD7gBlKCAFaUwyXF9lLl+wU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ce88RX6r; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ce88RX6r" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 969C71F000FF; Tue, 29 Sep 2026 14:12:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790691172; bh=5d3j4oZJbOGHf4Fh1WOMNGVzyhZ1G2+m/HNMTy3caGA=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ce88RX6rKynbAyabo82UW6YeDLa1ob2kh0gI/4+KFRF1XkpuYSlQt5QdNAw8+qv3j l/em/aAgR9iNnd9qW89SnK1oAh1ZC4L8DF6vdvEKMF5pCkqWpluQueWYWK9lARggVW 0qYr/zwJpDEeGmC35hQd27BqVpuDvQ9hKkHn0VnJq9jpR//pZPmczOGsPKFn9YzJ2y KR8lp5Y6ca4pkfgPGe+aCK40Mt0MaOPXPDKre8A+UGvVg+d7H6gx57GYilXfvBVEjP ZUUQ75VVnmMNv7Qit4l+wrHX6Mu+2NrNi8QEZP4qK9Takhi82GfVQX6+Su7ccv+663 mlBzgzcWE8X8A== From: Sasha Levin To: stable@vger.kernel.org Cc: Hui Peng , Jeremy Kerr , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.1.y 4/4] mctp: route: iterate socket tag list in mctp_lookup_prealloc_tag() Date: Tue, 29 Sep 2026 10:12:48 -0400 Message-ID: <20260929141248.3537868-4-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260929141248.3537868-1-sashal@kernel.org> References: <2026092919-helpful-hydrogen-8802@gregkh> <20260929141248.3537868-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Hui Peng [ Upstream commit 26cc0e69cce062cd3aa6fae33074684669c35a71 ] When a socket transmits a packet with MCTP_TAG_PREALLOC set, mctp_lookup_prealloc_tag() iterates over the per-netns &mns->keys list and matches netid, req_tag, peer_addr, and manual_alloc, without checking whether tmp->sk == &msk->sk. This allows any MCTP socket in the same network namespace to use and consume another socket's preallocated tag. Iterate the socket's own tag list (&msk->keys via sklist) instead of the namespace-wide &mns->keys list in mctp_lookup_prealloc_tag(), ensuring that only tags allocated by msk are matched. Tested in QEMU against Linux 7.3.0-rc3 by allocating a manual tag (0x18) on socket A via SIOCMCTPALLOCTAG for peer EID 9 and sending a 4-byte message with MCTP_TAG_PREALLOC from socket B in the same network namespace. On the unfixed kernel, sendto(sock_b) using socket A's preallocated tag succeeds (ret = 4); with this patch applied, sendto(sock_b) fails with -ENOENT (errno = 2) while sendto(sock_a) succeeds (ret = 4). Fixes: 63ed1aab3d40 ("mctp: Add SIOCMCTP{ALLOC,DROP}TAG ioctls for tag control") Suggested-by: Jeremy Kerr Cc: stable@vger.kernel.org Signed-off-by: Hui Peng Link: https://patch.msgid.link/20260921051002.1656692-1-benquike@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/mctp/route.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/mctp/route.c b/net/mctp/route.c index 95ba7fce1582d..7e2d43184eae4 100644 --- a/net/mctp/route.c +++ b/net/mctp/route.c @@ -758,7 +758,7 @@ static struct mctp_sk_key *mctp_lookup_prealloc_tag(struct mctp_sock *msk, spin_lock_irqsave(&mns->keys_lock, flags); - hlist_for_each_entry(tmp, &mns->keys, hlist) { + hlist_for_each_entry(tmp, &msk->keys, sklist) { if (tmp->net != netid) continue; -- 2.53.0