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 5603E13CFAE; Fri, 29 Mar 2024 12:31:20 +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=1711715480; cv=none; b=OJG4xk/lK6S670VjJJby0URxDWJYhgNyOdOD/tZ+HgH/q30UbZPR6ZUMemmniP+8M63es4O0k/VzxzaGHTitf3QUyWujowxMMpSSJWgq18tsUE8t3AKR11WGadkOpmO6I6G3PT8H9i+0xWxLdJo1wPZP1Lu0dgybo3wB+qc2W/0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711715480; c=relaxed/simple; bh=2XkywHGTNla9wNUnN56Y6gr1IeKydyjwYr37lT38rYY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=gLO965hDQz4udQuBrvTn7ZKl1oBP/vvPyf6VUWCq8oLH/tjhYIyGHo7S0vBaLEdEP8e6xOiJyHZxQhv7Yi9lAimEV5OYVqN65mZHNeu1skoYcD5ZsPHDhNryrmBq1Sz0XlHCuwp2nv8dVT3jCVs6GhFxItBu6C6dLfUwGvXfvHI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=X0Rmn3lh; 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="X0Rmn3lh" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 54D7DC433F1; Fri, 29 Mar 2024 12:31:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1711715479; bh=2XkywHGTNla9wNUnN56Y6gr1IeKydyjwYr37lT38rYY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=X0Rmn3lhIwez5d+VgogTtaf6bXlSXctrsj3vhKUDAU7BIPWaoNgtxradqtN8vUwzu xq8lXg0iMXttZ2e6nIfkGwkO28A3lVFYy7zSt/SUYK6rg/75A+HJSIiZZkxneZWSZo f+k4pEFxkeePYNDArDXz1n9YzMvEIdQEYrfBS4Y6ieshR+aBeSAe+uJgPGBgZ8MEfG z697BBz0MGONBm33r/JPDEkaClXKrShE446hHVV3a1Yw2iyWGkt9MxrvKnukF1bac6 mu7XN08xyFPzsE5uI8Jpe6pPGQkUZg7ZsL4tOL+9J2rQda4cl11VaSCXae+zAFRCzk d85IG5NRRUwwA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Kees Cook , Sasha Levin , linux-hardening@vger.kernel.org Subject: [PATCH AUTOSEL 6.6 40/52] overflow: Allow non-type arg to type_max() and type_min() Date: Fri, 29 Mar 2024 08:29:10 -0400 Message-ID: <20240329122956.3083859-40-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240329122956.3083859-1-sashal@kernel.org> References: <20240329122956.3083859-1-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 6.6.23 Content-Transfer-Encoding: 8bit From: Kees Cook [ Upstream commit bd1ebf2467f9c5d157bec7b025e83f8ffdae1318 ] A common use of type_max() is to find the max for the type of a variable. Using the pattern type_max(typeof(var)) is needlessly verbose. Instead, since typeof(type) == type we can just explicitly call typeof() on the argument to type_max() and type_min(). Add wrappers for readability. We can do some replacements right away: $ git grep '\btype_\(min\|max\)(typeof' | wc -l 11 Link: https://lore.kernel.org/r/20240301062221.work.840-kees@kernel.org Signed-off-by: Kees Cook Signed-off-by: Sasha Levin --- include/linux/overflow.h | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/include/linux/overflow.h b/include/linux/overflow.h index f9b60313eaea2..e04f679476473 100644 --- a/include/linux/overflow.h +++ b/include/linux/overflow.h @@ -31,8 +31,10 @@ * credit to Christian Biere. */ #define __type_half_max(type) ((type)1 << (8*sizeof(type) - 1 - is_signed_type(type))) -#define type_max(T) ((T)((__type_half_max(T) - 1) + __type_half_max(T))) -#define type_min(T) ((T)((T)-type_max(T)-(T)1)) +#define __type_max(T) ((T)((__type_half_max(T) - 1) + __type_half_max(T))) +#define type_max(t) __type_max(typeof(t)) +#define __type_min(T) ((T)((T)-type_max(T)-(T)1)) +#define type_min(t) __type_min(typeof(t)) /* * Avoids triggering -Wtype-limits compilation warning, @@ -130,10 +132,10 @@ static inline bool __must_check __must_check_overflow(bool overflow) #define __overflows_type_constexpr(x, T) ( \ is_unsigned_type(typeof(x)) ? \ - (x) > type_max(typeof(T)) : \ + (x) > type_max(T) : \ is_unsigned_type(typeof(T)) ? \ - (x) < 0 || (x) > type_max(typeof(T)) : \ - (x) < type_min(typeof(T)) || (x) > type_max(typeof(T))) + (x) < 0 || (x) > type_max(T) : \ + (x) < type_min(T) || (x) > type_max(T)) #define __overflows_type(x, T) ({ \ typeof(T) v = 0; \ -- 2.43.0