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 Received: from picard.linux.it (picard.linux.it [213.254.12.146]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id DA555CDB474 for ; Tue, 17 Oct 2023 12:40:40 +0000 (UTC) Received: from picard.linux.it (localhost [IPv6:::1]) by picard.linux.it (Postfix) with ESMTP id 0D55B3CEDF4 for ; Tue, 17 Oct 2023 14:40:39 +0200 (CEST) Received: from in-2.smtp.seeweb.it (in-2.smtp.seeweb.it [IPv6:2001:4b78:1:20::2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-384)) (No client certificate requested) by picard.linux.it (Postfix) with ESMTPS id AD78F3CD0F6 for ; Tue, 17 Oct 2023 14:40:27 +0200 (CEST) Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by in-2.smtp.seeweb.it (Postfix) with ESMTPS id B55886003BD for ; Tue, 17 Oct 2023 14:40:26 +0200 (CEST) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id B8E191FF19; Tue, 17 Oct 2023 12:40:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1697546425; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=K9tCjbuAdUlkjicI804CwXBTbx0I02EHMFmrTzYtqdo=; b=M47kbmELlkDhVsWYyJEDFcp1qwoZtrsEMv+knwf+YTr915dt20/CBDhaxTl+2Mf4YRGCEj upOXLF++gKG9bMLtRJKF+jSY73oKfIqFBnQzuinhBCMBHP4tBqd7AAq4A33VbMIOwbnSDh naoshN80pnULl0a5EKUEzjKdQABU6SQ= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1697546425; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=K9tCjbuAdUlkjicI804CwXBTbx0I02EHMFmrTzYtqdo=; b=qZ2puarsgPhsKYJwU8g58utl685E1iE4pbTVJjHjXosZOSkaeILOjNv9okjByKfpOogzNb mYX+T7Y8DMrNuoDQ== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id A5B6B13597; Tue, 17 Oct 2023 12:40:25 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id fwoEKLmALmVWWgAAMHmgww (envelope-from ); Tue, 17 Oct 2023 12:40:25 +0000 Date: Tue, 17 Oct 2023 14:41:01 +0200 From: Cyril Hrubis To: Petr Vorel Message-ID: References: <20230908141414.28359-1-andrea.cervesato@suse.de> <20230908141414.28359-3-andrea.cervesato@suse.de> <20231017113509.GA931108@pevik> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20231017113509.GA931108@pevik> Authentication-Results: smtp-out2.suse.de; none X-Spamd-Result: default: False [-3.62 / 50.00]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_THREE(0.00)[4]; TO_DN_SOME(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_GOOD(-0.10)[text/plain]; NEURAL_HAM_LONG(-3.00)[-1.000]; DKIM_SIGNED(0.00)[suse.cz:s=susede2_rsa,suse.cz:s=susede2_ed25519]; NEURAL_HAM_SHORT(-1.00)[-1.000]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; MID_RHS_NOT_FQDN(0.50)[]; RCVD_COUNT_TWO(0.00)[2]; RCVD_TLS_ALL(0.00)[]; BAYES_HAM(-0.02)[53.63%] X-Virus-Scanned: clamav-milter 1.0.1 at in-2.smtp.seeweb.it X-Virus-Status: Clean Subject: Re: [LTP] [PATCH v2 2/2] Refactor getegid02 using new LTP API X-BeenThere: ltp@lists.linux.it X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux Test Project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: ltp@lists.linux.it, Richard Palethorpe Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ltp-bounces+ltp=archiver.kernel.org@lists.linux.it Sender: "ltp" Hi! > This code is based on Cyril's suggestion in v1 [1] > if (GID_SIZE_CHECK(st_egid)) > TST_EXP_EQ_LI(gid, st_egid); > else > tst_res(TPASS, "getegid() passed"); > > I wonder which system returns 16 bit gid? > > man getgid(2) says that originally there was only 16 bit, than kernel 2.4 added > support for 32 bit and the glibc getegid() wrapper transparently deal with this. > > Because even I compile as 32 bit: > > $ file getegid01_16 > getegid01_16: ELF 32-bit LSB pie executable, Intel 80386 > > I get comparison, thus 32 bit: > $ ./getegid01_16 > ... > getegid01.c:25: TPASS: gid == st_egid (1000) > > What am I missing? This obviously works since 1000 < 32767. As long as the GID fits 16bit integer everything works fine with 16bit syscalls. The check returns if the egid does fit and returns true if so. When the GID does not fit, kernel returns overflow GID, i.e. for all values bigger than 16 bit you get the same GID value that does not correspond to the actual GID value at all. So to make the check false, you have to set up the test user so that it has GID > 16bit integer maximum value. -- Cyril Hrubis chrubis@suse.cz -- Mailing list info: https://lists.linux.it/listinfo/ltp