Re: [PATCH] Use strscpy() instead of strcpy()

[Abdul Rahim]

On Tue, Nov 12, 2024 at 07:21:54AM +0100, Christophe JAILLET wrote:
> Le 11/11/2024 � 23:10, Abdul Rahim a �crit�:
> > strcpy() is generally considered unsafe and use of strscpy() is
> > recommended [1]
> > 
> > this fixes checkpatch warning:
> >      WARNING: Prefer strscpy over strcpy
> > 
> > Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strcpy [1]
> > Signed-off-by: Abdul Rahim <abdul.rahim@xxxxxxxxxxx>
> > ---
> >   fs/ceph/export.c | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/fs/ceph/export.c b/fs/ceph/export.c
> > index 44451749c544..0e5b3c7b3756 100644
> > --- a/fs/ceph/export.c
> > +++ b/fs/ceph/export.c
> > @@ -452,7 +452,7 @@ static int __get_snap_name(struct dentry *parent, char *name,
> >   		goto out;
> >   	if (ceph_snap(inode) == CEPH_SNAPDIR) {
> >   		if (ceph_snap(dir) == CEPH_NOSNAP) {
> > -			strcpy(name, fsc->mount_options->snapdir_name);
> > +			strscpy(name, fsc->mount_options->snapdir_name);
> 
> This does not compile because when the size of 'name' is not known at
> compilation time, you need to use the 3-argument version of strscpy().
> 
> Please always compile test your patches before sending them. Even, when the
> change looks trivial.
> 

Sure.

> CJ
> 
> >   			err = 0;
> >   		}
> >   		goto out;
> 
> 

Should it be: NAME_MAX+1 ? 

See: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/include/linux/exportfs.h?h=v6.12-rc7#n203