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 635C3328610; Tue, 16 Jun 2026 17:02:03 +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=1781629324; cv=none; b=DYEOQ14o3mFaKqwMN5Xg6TJuWDTcqQkLI0mGxb0VBGbq0wDDzeK+y1Kmdb41kCiiIua6AJeAFlSFql1HUJprJScLNcURA/y78lYdfA3edoQs7XQXRL/9XqRTI/eFyr13UD2uHSS7CK1fOgDA1l/LLryNNvR5xujGdCmcLjhDc9U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781629324; c=relaxed/simple; bh=z6TQ9h5RftEMSZktN2CbhnaiRMwB1i8L8qbPhusWy+8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=gEsy8js9gQ10XLycjCdWunwbOR6nZLJqSMrmAC+j9o1yvS++hIomUofbIwrAeMHqRgrrNLGMC5nvmiy0t1b30j4seo5usux6SGlQASrnZ0UO9hwYykO1CXaBM9zSX1l/pgYf/uNXJ7mXPbNZQLNnD1lvLkVeZgI3NOa6PlIHRrc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=d/6/oJzm; 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="d/6/oJzm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 332E81F000E9; Tue, 16 Jun 2026 17:02:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1781629323; bh=URG1ipTNvazTuZygNmk0QWcRBiB/f5qaWOo0QdZNVg8=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=d/6/oJzmD2Xutfe680g0nQE3LKS9g+bxmRPm2DOkg/K+L/iRmjoUM+w7P6eQfuS6E GXWMfcdxryVzvcV9vTYXGrfKtBf42rDbF0zCtweTonUZypQ15NnyP7wP4MXh+dBGL0 Kbx5plZoQCEazyUFmilwtHTGMJ7hpq6Qrr5jV9iE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Eric Dumazet , Tamir Shahar , Amit Klein , Willem de Bruijn , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Kumar Kartikeya Dwivedi , Song Liu , Yonghong Song , Jiri Olsa , John Fastabend , Stanislav Fomichev , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.6 264/452] tcp: restrict SO_ATTACH_FILTER to priv users Date: Tue, 16 Jun 2026 20:28:11 +0530 Message-ID: <20260616145131.477301079@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260616145117.796205997@linuxfoundation.org> References: <20260616145117.796205997@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-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit 5d39580f68e6ddeedd15e587282207489dfb3da2 ] This patch restricts the use of SO_ATTACH_FILTER (cBPF) on TCP sockets to users with CAP_NET_ADMIN capability. This blocks potential side-channel attack where an unprivileged application attaches a filter to leak TCP sequence/acknowledgment numbers. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet Reported-by: Tamir Shahar Reported-by: Amit Klein Cc: Willem de Bruijn Cc: Alexei Starovoitov Cc: Daniel Borkmann Cc: Andrii Nakryiko Cc: Martin KaFai Lau Cc: Eduard Zingerman Cc: Kumar Kartikeya Dwivedi Cc: Song Liu Cc: Yonghong Song Cc: Jiri Olsa Cc: John Fastabend Cc: Stanislav Fomichev Acked-by: Daniel Borkmann Reviewed-by: Willem de Bruijn Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/core/sock.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/net/core/sock.c b/net/core/sock.c index 267f771dda1cc2..87e6060c8bca7f 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -1311,6 +1311,11 @@ int sk_setsockopt(struct sock *sk, int level, int optname, case SO_ATTACH_FILTER: { struct sock_fprog fprog; + if (sk_is_tcp(sk) && + !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) { + ret = -EPERM; + break; + } ret = copy_bpf_fprog_from_user(&fprog, optval, optlen); if (!ret) ret = sk_attach_filter(&fprog, sk); -- 2.53.0