From mboxrd@z Thu Jan 1 00:00:00 1970 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 E01DC158DD0; Mon, 22 Apr 2024 23:54:51 +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=1713830092; cv=none; b=K0psDyYrNEtx9O20RYsS5bKENGmTMEw/fvLMMT9tUhBiCVNAEeMHezMAJNANpM3gB9rwI8TZNhY2cI5Wl2/OsQKAkHKe9KHry0OP7MesQjqkn/bJME3Rxm/p6a5EvQk6tJTmJuZhk0y/6w14FNj16WZX3b3R8KEby99Nfha2jKU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713830092; c=relaxed/simple; bh=kvJOM7xjD44q/yAl8Oz0aNffaTe2DNveM77rzWrMYgQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=NdO0mLvC0H3iYHTii8bF9NAF+ZsJbkz0qSmw/Sjfk5ggkm7o3QpeCJaE+wwkdUD6SlaL6U9J1WPTVceU97CJ5Vlv8iAEkhCTRQVvEBuY7pmxCgkbFg8llMxeapTneq1vmpl8anqpuTZaW8GsdK/QhMDl0JLA4Xblpe0xFnm1dlY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=oVGkr2CQ; 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="oVGkr2CQ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AB58BC113CC; Mon, 22 Apr 2024 23:54:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1713830091; bh=kvJOM7xjD44q/yAl8Oz0aNffaTe2DNveM77rzWrMYgQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oVGkr2CQMky/ycWoXRX3jnlmtzTIWoRcXvBDSg1nIZeMJ6QgQUjNi+KVYs2agHjgX IOLgrWKY3ieuzrxMgvGorH/UA+H3D3h7tTjskQnGpDP0nLsd1gAjG6pGkLQp+PZDjz Lo0LtGq+fyt3EMlV4fLIGQ3F87eWa28Xg5ZAXnbpqZG7+QW2tDEMMIFaIdZP4ofMj8 nswZFFlNOP+jOPlM3AxjpahRpYLKMOYeVsheb5FjYJmIrGUINRO5um1T/LSLq5Nf3l xchhwUoR6zWMbjN/ETtwGzECzRe0GCrsLwuuZiqnbQHYPQ9D3jDfMztUkD1G+zj49k xTFO6bAgivECg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Eric Dumazet , Jakub Kicinski , Sasha Levin , 0x7f454c46@gmail.com, davem@davemloft.net, noureddine@arista.com, dsahern@kernel.org, fruggeri@arista.com Subject: [PATCH AUTOSEL 6.8 24/43] net: add copy_safe_from_sockptr() helper Date: Mon, 22 Apr 2024 19:14:10 -0400 Message-ID: <20240422231521.1592991-24-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240422231521.1592991-1-sashal@kernel.org> References: <20240422231521.1592991-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.8.7 Content-Transfer-Encoding: 8bit From: Eric Dumazet [ Upstream commit 6309863b31dd80317cd7d6824820b44e254e2a9c ] copy_from_sockptr() helper is unsafe, unless callers did the prior check against user provided optlen. Too many callers get this wrong, lets add a helper to fix them and avoid future copy/paste bugs. Instead of : if (optlen < sizeof(opt)) { err = -EINVAL; break; } if (copy_from_sockptr(&opt, optval, sizeof(opt)) { err = -EFAULT; break; } Use : err = copy_safe_from_sockptr(&opt, sizeof(opt), optval, optlen); if (err) break; Signed-off-by: Eric Dumazet Link: https://lore.kernel.org/r/20240408082845.3957374-2-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- include/linux/sockptr.h | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/include/linux/sockptr.h b/include/linux/sockptr.h index 307961b41541a..317200cd3a603 100644 --- a/include/linux/sockptr.h +++ b/include/linux/sockptr.h @@ -50,11 +50,36 @@ static inline int copy_from_sockptr_offset(void *dst, sockptr_t src, return 0; } +/* Deprecated. + * This is unsafe, unless caller checked user provided optlen. + * Prefer copy_safe_from_sockptr() instead. + */ static inline int copy_from_sockptr(void *dst, sockptr_t src, size_t size) { return copy_from_sockptr_offset(dst, src, 0, size); } +/** + * copy_safe_from_sockptr: copy a struct from sockptr + * @dst: Destination address, in kernel space. This buffer must be @ksize + * bytes long. + * @ksize: Size of @dst struct. + * @optval: Source address. (in user or kernel space) + * @optlen: Size of @optval data. + * + * Returns: + * * -EINVAL: @optlen < @ksize + * * -EFAULT: access to userspace failed. + * * 0 : @ksize bytes were copied + */ +static inline int copy_safe_from_sockptr(void *dst, size_t ksize, + sockptr_t optval, unsigned int optlen) +{ + if (optlen < ksize) + return -EINVAL; + return copy_from_sockptr(dst, optval, ksize); +} + static inline int copy_struct_from_sockptr(void *dst, size_t ksize, sockptr_t src, size_t usize) { -- 2.43.0