From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 90A7017731 for ; Wed, 9 Aug 2023 11:06:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 15C35C433C8; Wed, 9 Aug 2023 11:06:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1691579196; bh=CZNTdOr0qThjqT/wf9+TGGciE3frlEIOaIt1tsNMhY8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YvrphXCZgQ7LXT1uxsEEYpZJi+G2pjiAR1sh2WeK7SjXDA4cNm+AMonSJkCxtwU7t 4juoQ9BTzMN+s7I6l/WNkDZ3EAjeNs0h4w4RhYue5Rk2SKHNv8qUOMjjNcpv0tEyB2 QpK9PUrbqkUZmfM/2GXFm/xXVXjGkebPcF+iuAuI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Tim Gardner , kernel test robot , Ron Economos , Nathan Chancellor , Nick Desaulniers , Fabian Frederick , Christian Marangi , Christian Brauner Subject: [PATCH 4.14 081/204] jffs2: reduce stack usage in jffs2_build_xattr_subsystem() Date: Wed, 9 Aug 2023 12:40:19 +0200 Message-ID: <20230809103645.378008760@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230809103642.552405807@linuxfoundation.org> References: <20230809103642.552405807@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Fabian Frederick commit 1168f095417643f663caa341211e117db552989f upstream. Use kcalloc() for allocation/flush of 128 pointers table to reduce stack usage. Function now returns -ENOMEM or 0 on success. stackusage Before: ./fs/jffs2/xattr.c:775 jffs2_build_xattr_subsystem 1208 dynamic,bounded After: ./fs/jffs2/xattr.c:775 jffs2_build_xattr_subsystem 192 dynamic,bounded Also update definition when CONFIG_JFFS2_FS_XATTR is not enabled Tested with an MTD mount point and some user set/getfattr. Many current target on OpenWRT also suffer from a compilation warning (that become an error with CONFIG_WERROR) with the following output: fs/jffs2/xattr.c: In function 'jffs2_build_xattr_subsystem': fs/jffs2/xattr.c:887:1: error: the frame size of 1088 bytes is larger than 1024 bytes [-Werror=frame-larger-than=] 887 | } | ^ Using dynamic allocation fix this compilation warning. Fixes: c9f700f840bd ("[JFFS2][XATTR] using 'delete marker' for xdatum/xref deletion") Reported-by: Tim Gardner Reported-by: kernel test robot Reported-by: Ron Economos Reported-by: Nathan Chancellor Reviewed-by: Nick Desaulniers Signed-off-by: Fabian Frederick Signed-off-by: Christian Marangi Cc: stable@vger.kernel.org Message-Id: <20230506045612.16616-1-ansuelsmth@gmail.com> Signed-off-by: Christian Brauner Signed-off-by: Greg Kroah-Hartman --- fs/jffs2/build.c | 5 ++++- fs/jffs2/xattr.c | 13 +++++++++---- fs/jffs2/xattr.h | 4 ++-- 3 files changed, 15 insertions(+), 7 deletions(-) --- a/fs/jffs2/build.c +++ b/fs/jffs2/build.c @@ -211,7 +211,10 @@ static int jffs2_build_filesystem(struct ic->scan_dents = NULL; cond_resched(); } - jffs2_build_xattr_subsystem(c); + ret = jffs2_build_xattr_subsystem(c); + if (ret) + goto exit; + c->flags &= ~JFFS2_SB_FLAG_BUILDING; dbg_fsbuild("FS build complete\n"); --- a/fs/jffs2/xattr.c +++ b/fs/jffs2/xattr.c @@ -772,10 +772,10 @@ void jffs2_clear_xattr_subsystem(struct } #define XREF_TMPHASH_SIZE (128) -void jffs2_build_xattr_subsystem(struct jffs2_sb_info *c) +int jffs2_build_xattr_subsystem(struct jffs2_sb_info *c) { struct jffs2_xattr_ref *ref, *_ref; - struct jffs2_xattr_ref *xref_tmphash[XREF_TMPHASH_SIZE]; + struct jffs2_xattr_ref **xref_tmphash; struct jffs2_xattr_datum *xd, *_xd; struct jffs2_inode_cache *ic; struct jffs2_raw_node_ref *raw; @@ -784,9 +784,12 @@ void jffs2_build_xattr_subsystem(struct BUG_ON(!(c->flags & JFFS2_SB_FLAG_BUILDING)); + xref_tmphash = kcalloc(XREF_TMPHASH_SIZE, + sizeof(struct jffs2_xattr_ref *), GFP_KERNEL); + if (!xref_tmphash) + return -ENOMEM; + /* Phase.1 : Merge same xref */ - for (i=0; i < XREF_TMPHASH_SIZE; i++) - xref_tmphash[i] = NULL; for (ref=c->xref_temp; ref; ref=_ref) { struct jffs2_xattr_ref *tmp; @@ -884,6 +887,8 @@ void jffs2_build_xattr_subsystem(struct "%u of xref (%u dead, %u orphan) found.\n", xdatum_count, xdatum_unchecked_count, xdatum_orphan_count, xref_count, xref_dead_count, xref_orphan_count); + kfree(xref_tmphash); + return 0; } struct jffs2_xattr_datum *jffs2_setup_xattr_datum(struct jffs2_sb_info *c, --- a/fs/jffs2/xattr.h +++ b/fs/jffs2/xattr.h @@ -71,7 +71,7 @@ static inline int is_xattr_ref_dead(stru #ifdef CONFIG_JFFS2_FS_XATTR extern void jffs2_init_xattr_subsystem(struct jffs2_sb_info *c); -extern void jffs2_build_xattr_subsystem(struct jffs2_sb_info *c); +extern int jffs2_build_xattr_subsystem(struct jffs2_sb_info *c); extern void jffs2_clear_xattr_subsystem(struct jffs2_sb_info *c); extern struct jffs2_xattr_datum *jffs2_setup_xattr_datum(struct jffs2_sb_info *c, @@ -103,7 +103,7 @@ extern ssize_t jffs2_listxattr(struct de #else #define jffs2_init_xattr_subsystem(c) -#define jffs2_build_xattr_subsystem(c) +#define jffs2_build_xattr_subsystem(c) (0) #define jffs2_clear_xattr_subsystem(c) #define jffs2_xattr_do_crccheck_inode(c, ic)