From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.223.130]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3667A56757; Tue, 26 Mar 2024 09:54:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=195.135.223.130 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711446846; cv=none; b=g5oQDRf6GdJqUIAjaQLx3X72AwFEV3N8UcWs8tVX+kJHbm3CWngD5xPxqdtvXelkezFIv+D3HDtFZwVAqhIpAmmPCaDAhsBr1xRwnwBByxdnTPX+WVvNnpQdSqwRQDxDvE/89mj4/wOsuVJP/d7HiPfmV3rdrN7CudStPCFX5JY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711446846; c=relaxed/simple; bh=EDdDtVa8zpFKLiXUwYaid9C7CijL8vV8TJ2knmO560Y=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=uB3wguhlz+KbqGMSeOp3o8jQClnF0ciTeO7tyYxV5RnCpuzUrXkfAttybXNen5UQvYBDGmv6ilVJ+j7AOfCx0VCopklk8VKZizjs1k0izyoPiBT42+hAKmQnZExMARjgjRXntwf70dynsdSfq0Bke0VOWiqulhhaPbLdYvuRaho= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=suse.cz; spf=pass smtp.mailfrom=suse.cz; dkim=pass (1024-bit key) header.d=suse.cz header.i=@suse.cz header.b=X67Rp39H; dkim=permerror (0-bit key) header.d=suse.cz header.i=@suse.cz header.b=8NstOqXY; dkim=pass (1024-bit key) header.d=suse.cz header.i=@suse.cz header.b=X67Rp39H; dkim=permerror (0-bit key) header.d=suse.cz header.i=@suse.cz header.b=8NstOqXY; arc=none smtp.client-ip=195.135.223.130 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=suse.cz Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=suse.cz Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=suse.cz header.i=@suse.cz header.b="X67Rp39H"; dkim=permerror (0-bit key) header.d=suse.cz header.i=@suse.cz header.b="8NstOqXY"; dkim=pass (1024-bit key) header.d=suse.cz header.i=@suse.cz header.b="X67Rp39H"; dkim=permerror (0-bit key) header.d=suse.cz header.i=@suse.cz header.b="8NstOqXY" Received: from imap2.dmz-prg2.suse.org (imap2.dmz-prg2.suse.org [IPv6:2a07:de40:b281:104:10:150:64:98]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id 81FB2353A0; Tue, 26 Mar 2024 09:54:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1711446841; 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=AZdWoTycjyxZmxKXrCj0zVJl37+mzb3tmzUWtRx1AM4=; b=X67Rp39HWkdE1rUHyo2nSoYTwvk8SWeBDHuk8pong4sblUYNOf4rZMVdlZ6mBeOKXiQ93x 5zelL5paqnwErw9EvB6WsAysYV2j4MKxEaCSJ19GoMNAI0D8m7NodSEOGhM3+19NQIRUFu TqW6+xixmQHfRRxL3uXPoTGVSyf9tFk= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1711446841; 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=AZdWoTycjyxZmxKXrCj0zVJl37+mzb3tmzUWtRx1AM4=; b=8NstOqXYmLMekpDisOnB4Fhz3AS5Pmd9kbJ4y418Qh7Ns2ZBn+bxPhZvacIhgxwfIFe6ct c619yQg8+g1kV7CQ== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1711446841; 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=AZdWoTycjyxZmxKXrCj0zVJl37+mzb3tmzUWtRx1AM4=; b=X67Rp39HWkdE1rUHyo2nSoYTwvk8SWeBDHuk8pong4sblUYNOf4rZMVdlZ6mBeOKXiQ93x 5zelL5paqnwErw9EvB6WsAysYV2j4MKxEaCSJ19GoMNAI0D8m7NodSEOGhM3+19NQIRUFu TqW6+xixmQHfRRxL3uXPoTGVSyf9tFk= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1711446841; 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=AZdWoTycjyxZmxKXrCj0zVJl37+mzb3tmzUWtRx1AM4=; b=8NstOqXYmLMekpDisOnB4Fhz3AS5Pmd9kbJ4y418Qh7Ns2ZBn+bxPhZvacIhgxwfIFe6ct c619yQg8+g1kV7CQ== Received: from imap2.dmz-prg2.suse.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by imap2.dmz-prg2.suse.org (Postfix) with ESMTPS id 6F3B213587; Tue, 26 Mar 2024 09:54:01 +0000 (UTC) Received: from dovecot-director2.suse.de ([10.150.64.162]) by imap2.dmz-prg2.suse.org with ESMTPSA id vMnMGjmbAmbzCgAAn2gu4w (envelope-from ); Tue, 26 Mar 2024 09:54:01 +0000 Received: by quack3.suse.cz (Postfix, from userid 1000) id 051DCA0812; Tue, 26 Mar 2024 10:53:56 +0100 (CET) Date: Tue, 26 Mar 2024 10:53:56 +0100 From: Jan Kara To: "Gustavo A. R. Silva" Cc: Jan Kara , Amir Goldstein , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: Re: [PATCH v2][next] fsnotify: Avoid -Wflex-array-member-not-at-end warning Message-ID: <20240326095356.sntn4xtroguimfow@quack3> References: Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Spam-Level: Authentication-Results: smtp-out1.suse.de; dkim=pass header.d=suse.cz header.s=susede2_rsa header.b=X67Rp39H; dkim=pass header.d=suse.cz header.s=susede2_ed25519 header.b=8NstOqXY X-Rspamd-Server: rspamd2.dmz-prg2.suse.org X-Spamd-Result: default: False [-4.01 / 50.00]; RCVD_VIA_SMTP_AUTH(0.00)[]; ARC_NA(0.00)[]; R_DKIM_ALLOW(-0.20)[suse.cz:s=susede2_rsa,suse.cz:s=susede2_ed25519]; SPAMHAUS_XBL(0.00)[2a07:de40:b281:104:10:150:64:98:from]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; FREEMAIL_ENVRCPT(0.00)[gmail.com]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_GOOD(-0.10)[text/plain]; NEURAL_HAM_LONG(-1.00)[-1.000]; RCPT_COUNT_FIVE(0.00)[6]; NEURAL_HAM_SHORT(-0.20)[-1.000]; RCVD_COUNT_THREE(0.00)[3]; DKIM_SIGNED(0.00)[suse.cz:s=susede2_rsa,suse.cz:s=susede2_ed25519]; MX_GOOD(-0.01)[]; DKIM_TRACE(0.00)[suse.cz:+]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.cz:dkim,suse.com:email]; FUZZY_BLOCKED(0.00)[rspamd.com]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; MID_RHS_NOT_FQDN(0.50)[]; FREEMAIL_CC(0.00)[suse.cz,gmail.com,vger.kernel.org]; RCVD_TLS_ALL(0.00)[]; BAYES_HAM(-3.00)[100.00%] X-Spam-Score: -4.01 X-Rspamd-Queue-Id: 81FB2353A0 X-Spam-Flag: NO On Mon 25-03-24 19:36:02, Gustavo A. R. Silva wrote: > Use the `DEFINE_FLEX()` helper for an on-stack definition of a > flexible structure where the size of the flexible-array member > is known at compile-time, and refactor the rest of the code, > accordingly. > > So, with these changes, fix the following warning: > fs/notify/fdinfo.c:45:36: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] > > Link: https://github.com/KSPP/linux/issues/202 > Signed-off-by: Gustavo A. R. Silva Nice! I've added the patch to my tree. Honza > --- > Changes in v2: > - Use DEFINE_FLEX() instead of struct_group_tagged(). > > v1: > - Link: https://lore.kernel.org/linux-hardening/ZeeaRuTpuxInH6ZB@neat/ > > fs/notify/fdinfo.c | 20 ++++++++------------ > 1 file changed, 8 insertions(+), 12 deletions(-) > > diff --git a/fs/notify/fdinfo.c b/fs/notify/fdinfo.c > index 5c430736ec12..dec553034027 100644 > --- a/fs/notify/fdinfo.c > +++ b/fs/notify/fdinfo.c > @@ -41,29 +41,25 @@ static void show_fdinfo(struct seq_file *m, struct file *f, > #if defined(CONFIG_EXPORTFS) > static void show_mark_fhandle(struct seq_file *m, struct inode *inode) > { > - struct { > - struct file_handle handle; > - u8 pad[MAX_HANDLE_SZ]; > - } f; > + DEFINE_FLEX(struct file_handle, f, f_handle, handle_bytes, MAX_HANDLE_SZ); > int size, ret, i; > > - f.handle.handle_bytes = sizeof(f.pad); > - size = f.handle.handle_bytes >> 2; > + size = f->handle_bytes >> 2; > > - ret = exportfs_encode_fid(inode, (struct fid *)f.handle.f_handle, &size); > + ret = exportfs_encode_fid(inode, (struct fid *)f->f_handle, &size); > if ((ret == FILEID_INVALID) || (ret < 0)) { > WARN_ONCE(1, "Can't encode file handler for inotify: %d\n", ret); > return; > } > > - f.handle.handle_type = ret; > - f.handle.handle_bytes = size * sizeof(u32); > + f->handle_type = ret; > + f->handle_bytes = size * sizeof(u32); > > seq_printf(m, "fhandle-bytes:%x fhandle-type:%x f_handle:", > - f.handle.handle_bytes, f.handle.handle_type); > + f->handle_bytes, f->handle_type); > > - for (i = 0; i < f.handle.handle_bytes; i++) > - seq_printf(m, "%02x", (int)f.handle.f_handle[i]); > + for (i = 0; i < f->handle_bytes; i++) > + seq_printf(m, "%02x", (int)f->f_handle[i]); > } > #else > static void show_mark_fhandle(struct seq_file *m, struct inode *inode) > -- > 2.34.1 > -- Jan Kara SUSE Labs, CR