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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A0E3BEB64DD for ; Thu, 3 Aug 2023 13:58:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234382AbjHCN63 (ORCPT ); Thu, 3 Aug 2023 09:58:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44910 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235954AbjHCN61 (ORCPT ); Thu, 3 Aug 2023 09:58:27 -0400 Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.220.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5F4541707; Thu, 3 Aug 2023 06:58:26 -0700 (PDT) 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-out1.suse.de (Postfix) with ESMTPS id 20DCA21921; Thu, 3 Aug 2023 13:58:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1691071105; 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=8l+QAiD940oRfagIuqCPBAwWKWqvR6TFA25XDtgoPkE=; b=20UDKVqDDoMafg1Mf+6A9zpw7ulljTIIxJkfwahen3RJirthgW3vgD12GcdD6gu84d88SF e7OWVwk36aBpGccsIkQq8Z4CG8AMzmmAoeLgIdJMzp/aJpI+fI9/MLdf87ZgszjNxDvgjm DTKC91eKkrVbhOsk/s20of3Gjx8/Cro= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1691071105; 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=8l+QAiD940oRfagIuqCPBAwWKWqvR6TFA25XDtgoPkE=; b=otuL5jz4tvQUbwI2vKkPCD/IWnb+TBrbgd0USU/V8dEBtj/RB/LnMVp2ADEjGawPhz1QpB s3Ayb0o8YXSRhOCg== 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 0E9ED1333C; Thu, 3 Aug 2023 13:58:25 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id RVaOA4Gyy2T+fwAAMHmgww (envelope-from ); Thu, 03 Aug 2023 13:58:25 +0000 Received: by quack3.suse.cz (Postfix, from userid 1000) id 8692FA076B; Thu, 3 Aug 2023 15:58:24 +0200 (CEST) Date: Thu, 3 Aug 2023 15:58:24 +0200 From: Jan Kara To: Baokun Li Cc: linux-ext4@vger.kernel.org, tytso@mit.edu, adilger.kernel@dilger.ca, jack@suse.cz, ritesh.list@gmail.com, ojaswin@linux.ibm.com, linux-kernel@vger.kernel.org, yi.zhang@huawei.com, yangerkun@huawei.com, yukuai3@huawei.com Subject: Re: [PATCH v2 1/3] ext4: add two helper functions extent_logical_end() and pa_logical_end() Message-ID: <20230803135824.iue2mm53chrxrb2r@quack3> References: <20230724121059.11834-1-libaokun1@huawei.com> <20230724121059.11834-2-libaokun1@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230724121059.11834-2-libaokun1@huawei.com> Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org On Mon 24-07-23 20:10:57, Baokun Li wrote: > When we use lstart + len to calculate the end of free extent or prealloc > space, it may exceed the maximum value of 4294967295(0xffffffff) supported > by ext4_lblk_t and cause overflow, which may lead to various problems. > > Therefore, we add two helper functions, extent_logical_end() and > pa_logical_end(), to limit the type of end to loff_t, and also convert > lstart to loff_t for calculation to avoid overflow. > > Signed-off-by: Baokun Li Looks good to me. Feel free to add: Reviewed-by: Jan Kara Honza > --- > fs/ext4/mballoc.c | 9 +++------ > fs/ext4/mballoc.h | 14 ++++++++++++++ > 2 files changed, 17 insertions(+), 6 deletions(-) > > diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c > index 21b903fe546e..4cb13b3e41b3 100644 > --- a/fs/ext4/mballoc.c > +++ b/fs/ext4/mballoc.c > @@ -4432,7 +4432,7 @@ ext4_mb_normalize_request(struct ext4_allocation_context *ac, > > /* first, let's learn actual file size > * given current request is allocated */ > - size = ac->ac_o_ex.fe_logical + EXT4_C2B(sbi, ac->ac_o_ex.fe_len); > + size = extent_logical_end(sbi, &ac->ac_o_ex); > size = size << bsbits; > if (size < i_size_read(ac->ac_inode)) > size = i_size_read(ac->ac_inode); > @@ -4766,7 +4766,6 @@ ext4_mb_use_preallocated(struct ext4_allocation_context *ac) > struct ext4_inode_info *ei = EXT4_I(ac->ac_inode); > struct ext4_locality_group *lg; > struct ext4_prealloc_space *tmp_pa = NULL, *cpa = NULL; > - loff_t tmp_pa_end; > struct rb_node *iter; > ext4_fsblk_t goal_block; > > @@ -4862,9 +4861,7 @@ ext4_mb_use_preallocated(struct ext4_allocation_context *ac) > * pa can possibly satisfy the request hence check if it overlaps > * original logical start and stop searching if it doesn't. > */ > - tmp_pa_end = (loff_t)tmp_pa->pa_lstart + EXT4_C2B(sbi, tmp_pa->pa_len); > - > - if (ac->ac_o_ex.fe_logical >= tmp_pa_end) { > + if (ac->ac_o_ex.fe_logical >= pa_logical_end(sbi, tmp_pa)) { > spin_unlock(&tmp_pa->pa_lock); > goto try_group_pa; > } > @@ -5769,7 +5766,7 @@ static void ext4_mb_group_or_file(struct ext4_allocation_context *ac) > > group_pa_eligible = sbi->s_mb_group_prealloc > 0; > inode_pa_eligible = true; > - size = ac->ac_o_ex.fe_logical + EXT4_C2B(sbi, ac->ac_o_ex.fe_len); > + size = extent_logical_end(sbi, &ac->ac_o_ex); > isize = (i_size_read(ac->ac_inode) + ac->ac_sb->s_blocksize - 1) > >> bsbits; > > diff --git a/fs/ext4/mballoc.h b/fs/ext4/mballoc.h > index df6b5e7c2274..d7aeb5da7d86 100644 > --- a/fs/ext4/mballoc.h > +++ b/fs/ext4/mballoc.h > @@ -233,6 +233,20 @@ static inline ext4_fsblk_t ext4_grp_offs_to_block(struct super_block *sb, > (fex->fe_start << EXT4_SB(sb)->s_cluster_bits); > } > > +static inline loff_t extent_logical_end(struct ext4_sb_info *sbi, > + struct ext4_free_extent *fex) > +{ > + /* Use loff_t to avoid end exceeding ext4_lblk_t max. */ > + return (loff_t)fex->fe_logical + EXT4_C2B(sbi, fex->fe_len); > +} > + > +static inline loff_t pa_logical_end(struct ext4_sb_info *sbi, > + struct ext4_prealloc_space *pa) > +{ > + /* Use loff_t to avoid end exceeding ext4_lblk_t max. */ > + return (loff_t)pa->pa_lstart + EXT4_C2B(sbi, pa->pa_len); > +} > + > typedef int (*ext4_mballoc_query_range_fn)( > struct super_block *sb, > ext4_group_t agno, > -- > 2.31.1 > -- Jan Kara SUSE Labs, CR