[PATCH] lsm:fix a missing-check bug in smack_sb_eat_lsm_opts()

[Zhongjun Tan]

On Fri, 16 Apr 2021 13:36:01 +0000
Al Viro <viro at zeniv.linux.org.uk> wrote:

> On Fri, Apr 16, 2021 at 05:53:03PM +0800,  Zhongjun Tan wrote:
> 
> > @@ -710,13 +711,14 @@ static int smack_sb_eat_lsm_opts(char
> > *options, void **mnt_opts) token = match_opt_prefix(from, len,
> > &arg); if (token != Opt_error) {
> >  			arg = kmemdup_nul(arg, from + len - arg,
> > GFP_KERNEL);
> > +			if (!arg) {
> > +				rc = -ENOMEM;
> > +				goto free_mnt_opts;
> >  			rc = smack_add_opt(token, arg, mnt_opts);  
> 
> 			if (arg)
> 	  			rc = smack_add_opt(token, arg,
> mnt_opts); else
> 				rc = -ENOMEM;
> 
> and no other changes are needed anywhere...

update patch v3 , just four codes and no other changes are needed.