From patchwork Fri Aug 11 21:50:45 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhangjin Wu X-Patchwork-Id: 13351518 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0AF87C0015E for ; Fri, 11 Aug 2023 21:51:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237072AbjHKVvF (ORCPT ); Fri, 11 Aug 2023 17:51:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45128 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237070AbjHKVvE (ORCPT ); Fri, 11 Aug 2023 17:51:04 -0400 Received: from bg4.exmail.qq.com (bg4.exmail.qq.com [43.154.54.12]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 964DD2712; Fri, 11 Aug 2023 14:51:03 -0700 (PDT) X-QQ-mid: bizesmtp63t1691790647tk467uon Received: from linux-lab-host.localdomain ( [116.30.128.116]) by bizesmtp.qq.com (ESMTP) with id ; Sat, 12 Aug 2023 05:50:45 +0800 (CST) X-QQ-SSF: 01200000000000E0X000000A0000000 X-QQ-FEAT: cknW069rtVdcYll5qSTwzsTfqXrvv75L0qlCqnV/4/VuNNA7AGW2lTfMec+rQ gEw8mbCx55sIMZILg5KY6QqKA+LhLlKg5bADNzSAvAlfol9VlvGPKaKhHJ/bXqcbpBQY9gV C0DVP4IGf98tFitIlQSyk5om2TtXNcx+SX7xsxiCPx7YbfwTS64JfQSNKLwptd5ADVtfSyf I5AdAfTL6bbgRExXfcQMn7T9lmasM9eDj+0hWlw5iNtV8lDfnf2oti4bBDVfPw6G52Dnyto jTDMKgGG4xzfJdBamFQYhuWsLwhYy4TPPJB72surXE19oa0ZzXscT77AHrYFWUEZLX8ySFy 7taB/RHQeSTab8kW2cW9spWFSz7nxNBDKqV9hqMf48knKOe2WazBXHc7rPhhA== X-QQ-GoodBg: 0 X-BIZMAIL-ID: 10867541119786147020 From: Zhangjin Wu To: w@1wt.eu Cc: falcon@tinylab.org, david.laight@aculab.com, arnd@arndb.de, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, tanyuan@tinylab.org, thomas@t-8ch.de Subject: [PATCH v6 1/2] tools/nolibc: let sys_brk, sys_mmap and sys_mmap2 return long Date: Sat, 12 Aug 2023 05:50:45 +0800 Message-Id: <82b584cbda5cee8d5318986644a2a64ba749a098.1691788036.git.falcon@tinylab.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 X-QQ-SENDSIZE: 520 Feedback-ID: bizesmtp:tinylab.org:qybglogicsvrgz:qybglogicsvrgz5a-1 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Firstly, since the sys_* functions are internally used by our library routines, it is ok to let them preserve the 'long' return type of my_syscall macros, that means not necessary to return pointer like their library routines do. Secondly, in order to avoid the size inflating issues introduced by the sign extension, it is better to let __sysret() only accept integer input types, to do so, we must let all of the sys_* functions not return pointers. There are only three sys_* functions which return pointer, let's make them return 'long' instead of pointer. Link: https://lore.kernel.org/lkml/20230809221743.83107-1-falcon@tinylab.org/ Signed-off-by: Zhangjin Wu --- tools/include/nolibc/arch-s390.h | 4 ++-- tools/include/nolibc/sys.h | 16 ++++++++-------- 2 files changed, 10 insertions(+), 10 deletions(-) diff --git a/tools/include/nolibc/arch-s390.h b/tools/include/nolibc/arch-s390.h index 5d60fd43f883..6396c2a6bc3a 100644 --- a/tools/include/nolibc/arch-s390.h +++ b/tools/include/nolibc/arch-s390.h @@ -160,7 +160,7 @@ struct s390_mmap_arg_struct { }; static __attribute__((unused)) -void *sys_mmap(void *addr, size_t length, int prot, int flags, int fd, +long sys_mmap(void *addr, size_t length, int prot, int flags, int fd, off_t offset) { struct s390_mmap_arg_struct args = { @@ -172,7 +172,7 @@ void *sys_mmap(void *addr, size_t length, int prot, int flags, int fd, .offset = (unsigned long)offset }; - return (void *)my_syscall1(__NR_mmap, &args); + return my_syscall1(__NR_mmap, &args); } #define sys_mmap sys_mmap diff --git a/tools/include/nolibc/sys.h b/tools/include/nolibc/sys.h index 833d6c5e86dc..a28e7fbff448 100644 --- a/tools/include/nolibc/sys.h +++ b/tools/include/nolibc/sys.h @@ -74,9 +74,9 @@ long __sysret(unsigned long ret) */ static __attribute__((unused)) -void *sys_brk(void *addr) +long sys_brk(void *addr) { - return (void *)my_syscall1(__NR_brk, addr); + return my_syscall1(__NR_brk, addr); } static __attribute__((unused)) @@ -89,12 +89,12 @@ static __attribute__((unused)) void *sbrk(intptr_t inc) { /* first call to find current end */ - void *ret = sys_brk(0); + void *ret = (void *)sys_brk(0); - if (ret && sys_brk(ret + inc) == ret + inc) + if (ret && (void *)sys_brk(ret + inc) == ret + inc) return ret + inc; - return (void *)__sysret(-ENOMEM); + return (void *)__sysret((long)-ENOMEM); } @@ -658,7 +658,7 @@ int mknod(const char *path, mode_t mode, dev_t dev) #ifndef sys_mmap static __attribute__((unused)) -void *sys_mmap(void *addr, size_t length, int prot, int flags, int fd, +long sys_mmap(void *addr, size_t length, int prot, int flags, int fd, off_t offset) { int n; @@ -670,7 +670,7 @@ void *sys_mmap(void *addr, size_t length, int prot, int flags, int fd, n = __NR_mmap; #endif - return (void *)my_syscall6(n, addr, length, prot, flags, fd, offset); + return my_syscall6(n, addr, length, prot, flags, fd, offset); } #endif @@ -682,7 +682,7 @@ void *sys_mmap(void *addr, size_t length, int prot, int flags, int fd, static __attribute__((unused)) void *mmap(void *addr, size_t length, int prot, int flags, int fd, off_t offset) { - return (void *)__sysret((unsigned long)sys_mmap(addr, length, prot, flags, fd, offset)); + return (void *)__sysret(sys_mmap(addr, length, prot, flags, fd, offset)); } static __attribute__((unused)) From patchwork Fri Aug 11 21:51:53 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhangjin Wu X-Patchwork-Id: 13351521 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BC2A8C0015E for ; Fri, 11 Aug 2023 21:52:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236570AbjHKVwO (ORCPT ); Fri, 11 Aug 2023 17:52:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42298 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235401AbjHKVwO (ORCPT ); Fri, 11 Aug 2023 17:52:14 -0400 Received: from bg4.exmail.qq.com (bg4.exmail.qq.com [43.155.65.254]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1E957271B; Fri, 11 Aug 2023 14:52:10 -0700 (PDT) X-QQ-mid: bizesmtp69t1691790715t2l3imm8 Received: from linux-lab-host.localdomain ( [116.30.128.116]) by bizesmtp.qq.com (ESMTP) with id ; Sat, 12 Aug 2023 05:51:53 +0800 (CST) X-QQ-SSF: 01200000000000E0X000000A0000000 X-QQ-FEAT: jGGC4gWX7WFEuWrQD10QYevA6rKFR5eyLN27zADU7mMJyUa1X6F5wj5b8c1PO ER8oXLqoaZcj68vp2XW1IvvzWMXYjLid4rTDbWxcHY9+xK0LZ6TboYz9xrN1UuKrfZPeivH Xhx+frlWCSJTPIl4qTvNiv+IIPg62gxZBtdjgSzG1OWsfAsHQZwMgx7V1TgW3uPw9evoaY9 f/3qSx8aKzolxDdGprJ9lCbNnqC8BdKQhSeoDf1ZVL0vz1omtIq9sC7KeFcpXHcLENpcFN+ ZEMfFnvLJZED4528TgM/+SpuC2OxOWzKeNxwVnytS785YBa97JXf5RSeKCPgFQkYpErIUmN JyXdyk2gkVM2i9Ad6ukNE5KRQK4tVquu5jqDZvRRUNb6m1LNpMtGj4GfqQLSUQA0SHWLMTn X-QQ-GoodBg: 0 X-BIZMAIL-ID: 14313426769615256479 From: Zhangjin Wu To: w@1wt.eu Cc: falcon@tinylab.org, david.laight@aculab.com, arnd@arndb.de, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, tanyuan@tinylab.org, thomas@t-8ch.de Subject: [PATCH v6 2/2] tools/nolibc: fix up size inflate regression Date: Sat, 12 Aug 2023 05:51:53 +0800 Message-Id: <96624cc918092737d35dd539d184de06dba7a9b8.1691788036.git.falcon@tinylab.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 X-QQ-SENDSIZE: 520 Feedback-ID: bizesmtp:tinylab.org:qybglogicsvrgz:qybglogicsvrgz5a-1 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org As reported and suggested by Willy, the inline __sysret() helper introduces three types of conversions and increases the size: (1) the "unsigned long" argument to __sysret() forces a sign extension from all sys_* functions that used to return 'int' (2) the comparison with the error range now has to be performed on a 'unsigned long' instead of an 'int' (3) the return value from __sysret() is a 'long' (note, a signed long) which then has to be turned back to an 'int' before being returned by the caller to satisfy the caller's prototype. To fix up this, firstly, let's use macro instead of inline function to preserves the input type and avoids these useless conversions (1), (3). Secondly, since all of the sys_* functions have been converted to return integer, now, it is able to remove comparison to a 'unsigned long' -MAX_ERRNO (2) and restore the simple sign comparison as before. Suggested-by: Willy Tarreau Link: https://lore.kernel.org/lkml/20230806095846.GB10627@1wt.eu/ Signed-off-by: Zhangjin Wu --- tools/include/nolibc/sys.h | 27 ++++++++++----------------- 1 file changed, 10 insertions(+), 17 deletions(-) diff --git a/tools/include/nolibc/sys.h b/tools/include/nolibc/sys.h index a28e7fbff448..e0b68d3532b6 100644 --- a/tools/include/nolibc/sys.h +++ b/tools/include/nolibc/sys.h @@ -27,23 +27,16 @@ #include "errno.h" #include "types.h" - -/* Syscall return helper for library routines, set errno as -ret when ret is in - * range of [-MAX_ERRNO, -1] - * - * Note, No official reference states the errno range here aligns with musl - * (src/internal/syscall_ret.c) and glibc (sysdeps/unix/sysv/linux/sysdep.h) - */ - -static __inline__ __attribute__((unused, always_inline)) -long __sysret(unsigned long ret) -{ - if (ret >= (unsigned long)-MAX_ERRNO) { - SET_ERRNO(-(long)ret); - return -1; - } - return ret; -} +/* Syscall return helper, set errno as -ret when ret < 0 */ +#define __sysret(arg) \ +({ \ + __typeof__(arg) __ret = (arg); \ + if (__ret < 0) { \ + SET_ERRNO(-__ret); \ + __ret = -1L; \ + } \ + __ret; \ +}) /* Functions in this file only describe syscalls. They're declared static so * that the compiler usually decides to inline them while still being allowed