From 58a8fe7cb0775614d3292edbf63a9ff5125f95c0 Mon Sep 17 00:00:00 2001 From: Christian Marangi Date: Sat, 6 May 2023 07:06:09 +0200 Subject: [PATCH] generic: 5.15: add pending patch fixing compilation warning in jffs2 Current gcc set a limit for each stack and complain if this limit is not followed. JFSS2 in build_xattr function currently exceed the limit by allocating a massive array of struct of 128 elements. Introduce a pending patch that allocate this temp array dynamically fixing the compilation warning: 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 | } | ^ Affecting many target that require jffs2 support. Signed-off-by: Christian Marangi --- ...ck-usage-in-jffs2_build_xattr_subsys.patch | 121 ++++++++++++++++++ 1 file changed, 121 insertions(+) create mode 100644 target/linux/generic/pending-5.15/143-jffs2-reduce-stack-usage-in-jffs2_build_xattr_subsys.patch diff --git a/target/linux/generic/pending-5.15/143-jffs2-reduce-stack-usage-in-jffs2_build_xattr_subsys.patch b/target/linux/generic/pending-5.15/143-jffs2-reduce-stack-usage-in-jffs2_build_xattr_subsys.patch new file mode 100644 index 0000000000..e5a86dd29f --- /dev/null +++ b/target/linux/generic/pending-5.15/143-jffs2-reduce-stack-usage-in-jffs2_build_xattr_subsys.patch @@ -0,0 +1,121 @@ +From eee53f6eb7561f516b9c4bac829ce31c48096130 Mon Sep 17 00:00:00 2001 +From: Fabian Frederick +Date: Tue, 9 May 2017 22:30:03 +0200 +Subject: [PATCH] jffs2: reduce stack usage in jffs2_build_xattr_subsystem() + +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 +--- + 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) -- 2.30.2