From patchwork Fri Aug 7 16:58:30 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Florian Weimer X-Patchwork-Id: 40232 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 516D43840C2A; Fri, 7 Aug 2020 16:58:39 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 516D43840C2A DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1596819519; bh=d/u67XAjZxB6cisT+y2sWeQ4BJ7Zm4hZN+M3SZztHDk=; h=To:Subject:Date:List-Id:List-Unsubscribe:List-Archive:List-Post: List-Help:List-Subscribe:From:Reply-To:From; b=eFUYw2p4T/XdRTCrrUlnZdGhdbcMMXoBjjJki6Xu67VM7WcMnyyZtzBDc0sdazYgw iLHaqr0+wSy3QciRW2FX0oDCuEgllnmvrcs2CC3rtcKY5J8r+j2EBLa4+jrDKO8MHh BpzkIoY8rMaZ3BvILERQM5vMmyRivxvW/gUvaS50= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from us-smtp-1.mimecast.com (us-smtp-delivery-1.mimecast.com [207.211.31.120]) by sourceware.org (Postfix) with ESMTP id C3B323851C2B for ; Fri, 7 Aug 2020 16:58:37 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org C3B323851C2B Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-265-EyCtXdr4OvODpZ5H9GeRfQ-1; Fri, 07 Aug 2020 12:58:34 -0400 X-MC-Unique: EyCtXdr4OvODpZ5H9GeRfQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3AD9919057A0 for ; Fri, 7 Aug 2020 16:58:33 +0000 (UTC) Received: from oldenburg2.str.redhat.com (ovpn-112-167.ams2.redhat.com [10.36.112.167]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 82D3D87A44 for ; Fri, 7 Aug 2020 16:58:32 +0000 (UTC) To: libc-alpha@sourceware.org Subject: [PATCH] Linux: Use faccessat2 to implement faccessat (bug 18683) Date: Fri, 07 Aug 2020 18:58:30 +0200 Message-ID: <877dual7ex.fsf@oldenburg2.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.3 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-Spam-Status: No, score=-12.0 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Florian Weimer via Libc-alpha From: Florian Weimer Reply-To: Florian Weimer Errors-To: libc-alpha-bounces@sourceware.org Sender: "Libc-alpha" This provides correct AT_EACCESS handling and also takes Linux security modules into account. Tested on i686-linux-gnu, x86_64-linux-gnu. Built with build-many-glibcs.py. Reviewed-by: Adhemerval Zanella --- sysdeps/unix/sysv/linux/faccessat.c | 14 +++++++++++--- sysdeps/unix/sysv/linux/kernel-features.h | 8 ++++++++ 2 files changed, 19 insertions(+), 3 deletions(-) diff --git a/sysdeps/unix/sysv/linux/faccessat.c b/sysdeps/unix/sysv/linux/faccessat.c index e4f18ab2db..56cb6dcc8b 100644 --- a/sysdeps/unix/sysv/linux/faccessat.c +++ b/sysdeps/unix/sysv/linux/faccessat.c @@ -30,6 +30,13 @@ int faccessat (int fd, const char *file, int mode, int flag) { + int ret = INLINE_SYSCALL_CALL (faccessat2, fd, file, mode, flag); +#if __ASSUME_FACCESSAT2 + return ret; +#else + if (ret == 0 || errno != ENOSYS) + return ret; + if (flag & ~(AT_SYMLINK_NOFOLLOW | AT_EACCESS)) return INLINE_SYSCALL_ERROR_RETURN_VALUE (EINVAL); @@ -41,9 +48,9 @@ faccessat (int fd, const char *file, int mode, int flag) return -1; mode &= (X_OK | W_OK | R_OK); /* Clear any bogus bits. */ -#if R_OK != S_IROTH || W_OK != S_IWOTH || X_OK != S_IXOTH -# error Oops, portability assumptions incorrect. -#endif +# if R_OK != S_IROTH || W_OK != S_IWOTH || X_OK != S_IXOTH +# error Oops, portability assumptions incorrect. +# endif if (mode == F_OK) return 0; /* The file exists. */ @@ -68,4 +75,5 @@ faccessat (int fd, const char *file, int mode, int flag) return 0; return INLINE_SYSCALL_ERROR_RETURN_VALUE (EACCES); +#endif /* !__ASSUME_FACCESSAT2 */ } diff --git a/sysdeps/unix/sysv/linux/kernel-features.h b/sysdeps/unix/sysv/linux/kernel-features.h index 32533e94cf..a6bbc3c94e 100644 --- a/sysdeps/unix/sysv/linux/kernel-features.h +++ b/sysdeps/unix/sysv/linux/kernel-features.h @@ -214,4 +214,12 @@ # define __ASSUME_WAITID_PID0_P_PGID #endif +/* The faccessat2 system call was introduced across all architectures + in Linux 5.8. */ +#if __LINUX_KERNEL_VERSION >= 0x050800 +# define __ASSUME_FACCESSAT2 1 +#else +# define __ASSUME_FACCESSAT2 0 +#endif + #endif /* kernel-features.h */