| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <20250924202320.32333-16-farbere@amazon.com>
Date: Wed, 24 Sep 2025 20:23:16 +0000
From: Eliav Farber <farbere@...zon.com>
To: <linux@...linux.org.uk>, <richard@....at>,
<anton.ivanov@...bridgegreys.com>, <johannes@...solutions.net>,
<dave.hansen@...ux.intel.com>, <luto@...nel.org>, <peterz@...radead.org>,
<tglx@...utronix.de>, <mingo@...hat.com>, <bp@...en8.de>, <x86@...nel.org>,
<hpa@...or.com>, <tony.luck@...el.com>, <qiuxu.zhuo@...el.com>,
<mchehab@...nel.org>, <james.morse@....com>, <rric@...nel.org>,
<harry.wentland@....com>, <sunpeng.li@....com>, <Rodrigo.Siqueira@....com>,
<alexander.deucher@....com>, <christian.koenig@....com>,
<Xinhui.Pan@....com>, <airlied@...il.com>, <daniel@...ll.ch>,
<evan.quan@....com>, <james.qian.wang@....com>, <liviu.dudau@....com>,
<mihail.atanassov@....com>, <brian.starkey@....com>,
<maarten.lankhorst@...ux.intel.com>, <mripard@...nel.org>,
<tzimmermann@...e.de>, <robdclark@...il.com>, <quic_abhinavk@...cinc.com>,
<dmitry.baryshkov@...aro.org>, <sean@...rly.run>, <jdelvare@...e.com>,
<linux@...ck-us.net>, <linus.walleij@...aro.org>,
<dmitry.torokhov@...il.com>, <maz@...nel.org>, <wens@...e.org>,
<jernej.skrabec@...il.com>, <samuel@...lland.org>, <agk@...hat.com>,
<snitzer@...nel.org>, <dm-devel@...hat.com>, <rajur@...lsio.com>,
<davem@...emloft.net>, <edumazet@...gle.com>, <kuba@...nel.org>,
<pabeni@...hat.com>, <peppe.cavallaro@...com>,
<alexandre.torgue@...s.st.com>, <joabreu@...opsys.com>,
<mcoquelin.stm32@...il.com>, <krzysztof.kozlowski@...aro.org>,
<malattia@...ux.it>, <hdegoede@...hat.com>, <markgross@...nel.org>,
<artur.paszkiewicz@...el.com>, <jejb@...ux.ibm.com>,
<martin.petersen@...cle.com>, <sakari.ailus@...ux.intel.com>,
<gregkh@...uxfoundation.org>, <fei1.li@...el.com>, <clm@...com>,
<josef@...icpanda.com>, <dsterba@...e.com>, <jack@...e.com>, <tytso@....edu>,
<adilger.kernel@...ger.ca>, <dushistov@...l.ru>,
<luc.vanoostenryck@...il.com>, <rostedt@...dmis.org>, <mhiramat@...nel.org>,
<pmladek@...e.com>, <senozhatsky@...omium.org>,
<andriy.shevchenko@...ux.intel.com>, <linux@...musvillemoes.dk>,
<minchan@...nel.org>, <ngupta@...are.org>, <akpm@...ux-foundation.org>,
<yoshfuji@...ux-ipv6.org>, <dsahern@...nel.org>, <pablo@...filter.org>,
<kadlec@...filter.org>, <fw@...len.de>, <jmaloy@...hat.com>,
<ying.xue@...driver.com>, <andrii@...nel.org>, <mykolal@...com>,
<ast@...nel.org>, <daniel@...earbox.net>, <martin.lau@...ux.dev>,
<song@...nel.org>, <yhs@...com>, <john.fastabend@...il.com>,
<kpsingh@...nel.org>, <sdf@...gle.com>, <haoluo@...gle.com>,
<jolsa@...nel.org>, <shuah@...nel.org>, <keescook@...omium.org>,
<wad@...omium.org>, <willy@...radead.org>, <farbere@...zon.com>,
<sashal@...nel.org>, <ruanjinjie@...wei.com>, <quic_akhilpo@...cinc.com>,
<David.Laight@...LAB.COM>, <herve.codina@...tlin.com>,
<linux-arm-kernel@...ts.infradead.org>, <linux-kernel@...r.kernel.org>,
<linux-um@...ts.infradead.org>, <linux-edac@...r.kernel.org>,
<amd-gfx@...ts.freedesktop.org>, <dri-devel@...ts.freedesktop.org>,
<linux-arm-msm@...r.kernel.org>, <freedreno@...ts.freedesktop.org>,
<linux-hwmon@...r.kernel.org>, <linux-input@...r.kernel.org>,
<linux-sunxi@...ts.linux.dev>, <linux-media@...r.kernel.org>,
<netdev@...r.kernel.org>, <linux-stm32@...md-mailman.stormreply.com>,
<platform-driver-x86@...r.kernel.org>, <linux-scsi@...r.kernel.org>,
<linux-staging@...ts.linux.dev>, <linux-btrfs@...r.kernel.org>,
<linux-ext4@...r.kernel.org>, <linux-sparse@...r.kernel.org>,
<linux-mm@...ck.org>, <netfilter-devel@...r.kernel.org>,
<coreteam@...filter.org>, <tipc-discussion@...ts.sourceforge.net>,
<bpf@...r.kernel.org>, <linux-kselftest@...r.kernel.org>,
<stable@...r.kernel.org>
CC: Arnd Bergmann <arnd@...nel.org>, Christoph Hellwig <hch@...radead.org>,
Dan Carpenter <dan.carpenter@...aro.org>, "Jason A. Donenfeld"
<Jason@...c4.com>, Jens Axboe <axboe@...nel.dk>, Lorenzo Stoakes
<lorenzo.stoakes@...cle.com>, Mateusz Guzik <mjguzik@...il.com>, "Pedro
Falcato" <pedro.falcato@...il.com>
Subject: [PATCH 15/19 v6.1.y] minmax.h: reduce the #define expansion of min(), max() and clamp()
From: David Laight <David.Laight@...LAB.COM>
[ Upstream commit b280bb27a9f7c91ddab730e1ad91a9c18a051f41 ]
Since the test for signed values being non-negative only relies on
__builtion_constant_p() (not is_constexpr()) it can use the 'ux' variable
instead of the caller supplied expression. This means that the #define
parameters are only expanded twice. Once in the code and once quoted in
the error message.
Link: https://lkml.kernel.org/r/051afc171806425da991908ed8688a98@AcuMS.aculab.com
Signed-off-by: David Laight <david.laight@...lab.com>
Cc: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
Cc: Arnd Bergmann <arnd@...nel.org>
Cc: Christoph Hellwig <hch@...radead.org>
Cc: Dan Carpenter <dan.carpenter@...aro.org>
Cc: Jason A. Donenfeld <Jason@...c4.com>
Cc: Jens Axboe <axboe@...nel.dk>
Cc: Lorenzo Stoakes <lorenzo.stoakes@...cle.com>
Cc: Mateusz Guzik <mjguzik@...il.com>
Cc: Matthew Wilcox <willy@...radead.org>
Cc: Pedro Falcato <pedro.falcato@...il.com>
Signed-off-by: Andrew Morton <akpm@...ux-foundation.org>
Signed-off-by: Eliav Farber <farbere@...zon.com>
---
include/linux/minmax.h | 24 ++++++++++++------------
1 file changed, 12 insertions(+), 12 deletions(-)
diff --git a/include/linux/minmax.h b/include/linux/minmax.h
index 24e4b372649a..6f7ea669d305 100644
--- a/include/linux/minmax.h
+++ b/include/linux/minmax.h
@@ -46,10 +46,10 @@
* comparison, and these expressions only need to be careful to not cause
* warnings for pointer use.
*/
-#define __signed_type_use(x, ux) (2 + __is_nonneg(x, ux))
-#define __unsigned_type_use(x, ux) (1 + 2 * (sizeof(ux) < 4))
-#define __sign_use(x, ux) (is_signed_type(typeof(ux)) ? \
- __signed_type_use(x, ux) : __unsigned_type_use(x, ux))
+#define __signed_type_use(ux) (2 + __is_nonneg(ux))
+#define __unsigned_type_use(ux) (1 + 2 * (sizeof(ux) < 4))
+#define __sign_use(ux) (is_signed_type(typeof(ux)) ? \
+ __signed_type_use(ux) : __unsigned_type_use(ux))
/*
* Check whether a signed value is always non-negative.
@@ -71,13 +71,13 @@
#else
#define __signed_type(ux) typeof(__builtin_choose_expr(sizeof(ux) > 4, 1LL, 1L))
#endif
-#define __is_nonneg(x, ux) statically_true((__signed_type(ux))(x) >= 0)
+#define __is_nonneg(ux) statically_true((__signed_type(ux))(ux) >= 0)
-#define __types_ok(x, y, ux, uy) \
- (__sign_use(x, ux) & __sign_use(y, uy))
+#define __types_ok(ux, uy) \
+ (__sign_use(ux) & __sign_use(uy))
-#define __types_ok3(x, y, z, ux, uy, uz) \
- (__sign_use(x, ux) & __sign_use(y, uy) & __sign_use(z, uz))
+#define __types_ok3(ux, uy, uz) \
+ (__sign_use(ux) & __sign_use(uy) & __sign_use(uz))
#define __cmp_op_min <
#define __cmp_op_max >
@@ -92,7 +92,7 @@
#define __careful_cmp_once(op, x, y, ux, uy) ({ \
__auto_type ux = (x); __auto_type uy = (y); \
- BUILD_BUG_ON_MSG(!__types_ok(x, y, ux, uy), \
+ BUILD_BUG_ON_MSG(!__types_ok(ux, uy), \
#op"("#x", "#y") signedness error"); \
__cmp(op, ux, uy); })
@@ -109,7 +109,7 @@
static_assert(__builtin_choose_expr(__is_constexpr((lo) > (hi)), \
(lo) <= (hi), true), \
"clamp() low limit " #lo " greater than high limit " #hi); \
- BUILD_BUG_ON_MSG(!__types_ok3(val, lo, hi, uval, ulo, uhi), \
+ BUILD_BUG_ON_MSG(!__types_ok3(uval, ulo, uhi), \
"clamp("#val", "#lo", "#hi") signedness error"); \
__clamp(uval, ulo, uhi); })
@@ -149,7 +149,7 @@
#define __careful_op3(op, x, y, z, ux, uy, uz) ({ \
__auto_type ux = (x); __auto_type uy = (y);__auto_type uz = (z);\
- BUILD_BUG_ON_MSG(!__types_ok3(x, y, z, ux, uy, uz), \
+ BUILD_BUG_ON_MSG(!__types_ok3(ux, uy, uz), \
#op"3("#x", "#y", "#z") signedness error"); \
__cmp(op, ux, __cmp(op, uy, uz)); })
--
2.47.3
Powered by blists - more mailing lists