| Message ID | 1520970710-19732-1-git-send-email-s.mesoraca16@gmail.com (mailing list archive) |
|---|---|
| State | Mainlined |
| Headers | show |
On Tue, Mar 13, 2018 at 12:51 PM, Salvatore Mesoraca <s.mesoraca16@gmail.com> wrote: > Avoid a VLA[1] by using a real constant expression instead of a variable. > The compiler should be able to optimize the original code and avoid using > an actual VLA. Anyway this change is useful because it will avoid a false > positive with -Wvla, it might also help the compiler generating better > code. > > [1] https://lkml.org/lkml/2018/3/7/621 > > Signed-off-by: Salvatore Mesoraca <s.mesoraca16@gmail.com> Reviewed-by: Kees Cook <keescook@chromium.org> Andrew, can you take this? It seems the most recent patch to ocfs2 went through your tree... -Kees > --- > fs/ocfs2/namei.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/fs/ocfs2/namei.c b/fs/ocfs2/namei.c > index c801edd..41ef356 100644 > --- a/fs/ocfs2/namei.c > +++ b/fs/ocfs2/namei.c > @@ -2332,8 +2332,7 @@ int ocfs2_orphan_del(struct ocfs2_super *osb, > struct buffer_head *orphan_dir_bh, > bool dio) > { > - const int namelen = OCFS2_DIO_ORPHAN_PREFIX_LEN + OCFS2_ORPHAN_NAMELEN; > - char name[namelen + 1]; > + char name[OCFS2_DIO_ORPHAN_PREFIX_LEN + OCFS2_ORPHAN_NAMELEN + 1]; > struct ocfs2_dinode *orphan_fe; > int status = 0; > struct ocfs2_dir_lookup_result lookup = { NULL, }; > -- > 1.9.1 >
diff --git a/fs/ocfs2/namei.c b/fs/ocfs2/namei.c index c801edd..41ef356 100644 --- a/fs/ocfs2/namei.c +++ b/fs/ocfs2/namei.c @@ -2332,8 +2332,7 @@ int ocfs2_orphan_del(struct ocfs2_super *osb, struct buffer_head *orphan_dir_bh, bool dio) { - const int namelen = OCFS2_DIO_ORPHAN_PREFIX_LEN + OCFS2_ORPHAN_NAMELEN; - char name[namelen + 1]; + char name[OCFS2_DIO_ORPHAN_PREFIX_LEN + OCFS2_ORPHAN_NAMELEN + 1]; struct ocfs2_dinode *orphan_fe; int status = 0; struct ocfs2_dir_lookup_result lookup = { NULL, };
Avoid a VLA[1] by using a real constant expression instead of a variable. The compiler should be able to optimize the original code and avoid using an actual VLA. Anyway this change is useful because it will avoid a false positive with -Wvla, it might also help the compiler generating better code. [1] https://lkml.org/lkml/2018/3/7/621 Signed-off-by: Salvatore Mesoraca <s.mesoraca16@gmail.com> --- fs/ocfs2/namei.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)