From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4D622C433B4 for ; Sat, 15 May 2021 10:19:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 21180613F1 for ; Sat, 15 May 2021 10:19:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234838AbhEOKVF (ORCPT ); Sat, 15 May 2021 06:21:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:48704 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234905AbhEOKUf (ORCPT ); Sat, 15 May 2021 06:20:35 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 78078613F1; Sat, 15 May 2021 10:19:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1621073962; bh=OHYyLARVOpPFIbAcC7K6UIcn3rkRJrz96uQAgiEquDo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qcRi/50ljOQgAZf8i+VFhWF6uabdLpEfT7FHBTtxYuSMtemuV9LrEtTDSACDtVyfw salCHZmpn79xzNXb8B78wch24f//jkb6g+Fki5uCNdP8zNnv9UtDzG7e22EknaCACh mrPOxaZq4mdM1UsevzFRyixsupIwTAYWl49hqhEg3ck/tFFeNs7qINE0LN5ZtJSLfX H47TnEMDXTRGI4KAr0xEHobI2Wx0rYPpPUDbXbSo9MF06IlZHzfOPDMp3r4qLLEKvN GNVZauk3D4wviEHeU3e+G301vOcgnCYQ7ZvM9PTwWoO0iy7NC/13CbD7OJqRdxhixA j4vbx08vZ6TPA== From: Arnd Bergmann To: linux-arch@vger.kernel.org Cc: Arnd Bergmann , Christoph Hellwig , Al Viro , Vineet Gupta , Yoshinori Sato , Brian Cain , Geert Uytterhoeven , Paul Walmsley , Palmer Dabbelt , Albert Ou , Jeff Dike , Richard Weinberger , Anton Ivanov , Sid Manning , Andrew Morton , Mike Rapoport , linux-snps-arc@lists.infradead.org, linux-kernel@vger.kernel.org, uclinux-h8-devel@lists.sourceforge.jp, linux-hexagon@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-riscv@lists.infradead.org, linux-um@lists.infradead.org Subject: [PATCH 5/6] [v2] asm-generic: uaccess: remove inline strncpy_from_user/strnlen_user Date: Sat, 15 May 2021 12:18:02 +0200 Message-Id: <20210515101803.924427-6-arnd@kernel.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210515101803.924427-1-arnd@kernel.org> References: <20210515101803.924427-1-arnd@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-arch@vger.kernel.org From: Arnd Bergmann Consolidate the asm-generic implementation with the library version that is used everywhere else. These are the three versions for NOMMU kernels, which can in principle fall back to strncpy()/strnlen() as the version in asm-generic does, but this version is particularly inefficient when it scans the string one byte at a time twice. The generic version also lacks a check for user_addr_max(), but this is probably ok on NOMMU targets. Signed-off-by: Arnd Bergmann --- arch/h8300/Kconfig | 2 ++ arch/m68k/Kconfig | 4 +-- arch/riscv/Kconfig | 4 +-- include/asm-generic/uaccess.h | 46 ++++++----------------------------- 4 files changed, 14 insertions(+), 42 deletions(-) diff --git a/arch/h8300/Kconfig b/arch/h8300/Kconfig index 3e3e0f16f7e0..53dfd2d47e0e 100644 --- a/arch/h8300/Kconfig +++ b/arch/h8300/Kconfig @@ -11,6 +11,8 @@ config H8300 select GENERIC_IRQ_SHOW select FRAME_POINTER select GENERIC_CPU_DEVICES + select GENERIC_STRNCPY_FROM_USER + select GENERIC_STRNLEN_USER select MODULES_USE_ELF_RELA select COMMON_CLK select ARCH_WANT_FRAME_POINTERS diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig index ed6b8050e3ed..5f1aafa7b2e2 100644 --- a/arch/m68k/Kconfig +++ b/arch/m68k/Kconfig @@ -17,8 +17,8 @@ config M68K select GENERIC_CPU_DEVICES select GENERIC_IOMAP select GENERIC_IRQ_SHOW - select GENERIC_STRNCPY_FROM_USER if MMU - select GENERIC_STRNLEN_USER if MMU + select GENERIC_STRNCPY_FROM_USER + select GENERIC_STRNLEN_USER select HAVE_AOUT if MMU select HAVE_ASM_MODVERSIONS select HAVE_DEBUG_BUGVERBOSE diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index a8ad8eb76120..ada7a2918c05 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -55,8 +55,8 @@ config RISCV select GENERIC_PTDUMP if MMU select GENERIC_SCHED_CLOCK select GENERIC_SMP_IDLE_THREAD - select GENERIC_STRNCPY_FROM_USER if MMU - select GENERIC_STRNLEN_USER if MMU + select GENERIC_STRNCPY_FROM_USER + select GENERIC_STRNLEN_USER select GENERIC_TIME_VSYSCALL if MMU && 64BIT select HANDLE_DOMAIN_IRQ select HAVE_ARCH_AUDITSYSCALL diff --git a/include/asm-generic/uaccess.h b/include/asm-generic/uaccess.h index c03889cc904c..83a48f430951 100644 --- a/include/asm-generic/uaccess.h +++ b/include/asm-generic/uaccess.h @@ -119,6 +119,11 @@ static inline void set_fs(mm_segment_t fs) #ifndef uaccess_kernel #define uaccess_kernel() (get_fs().seg == KERNEL_DS.seg) #endif + +#ifndef user_addr_max +#define user_addr_max() (uaccess_kernel() ? ~0UL : TASK_SIZE) +#endif + #endif /* CONFIG_SET_FS */ #define access_ok(addr, size) __access_ok((unsigned long)(addr),(size)) @@ -243,44 +248,6 @@ static inline int __get_user_fn(size_t size, const void __user *ptr, void *x) extern int __get_user_bad(void) __attribute__((noreturn)); -/* - * Copy a null terminated string from userspace. - */ -#ifndef strncpy_from_user -static inline long -strncpy_from_user(char *dst, const char __user *src, long count) -{ - char *tmp; - - if (!access_ok(src, 1)) - return -EFAULT; - - strncpy(dst, (const char __force *)src, count); - for (tmp = dst; *tmp && count > 0; tmp++, count--) - ; - return (tmp - dst); -} -#endif - -#ifndef strnlen_user -/* - * Return the size of a string (including the ending 0) - * - * Return 0 on exception, a value greater than N if too long - * - * Unlike strnlen, strnlen_user includes the nul terminator in - * its returned count. Callers should check for a returned value - * greater than N as an indication the string is too long. - */ -static inline long strnlen_user(const char __user *src, long n) -{ - if (!access_ok(src, 1)) - return 0; - - return strnlen(src, n) + 1; -} -#endif - /* * Zero Userspace */ @@ -305,4 +272,7 @@ clear_user(void __user *to, unsigned long n) #include +extern long strncpy_from_user(char *dst, const char __user *src, long count); +extern long strnlen_user(const char __user *src, long n); + #endif /* __ASM_GENERIC_UACCESS_H */ -- 2.29.2