[dm-devel] [PATCH 2/2] multipath: don't check timestamps without a path

[Benjamin Marzinski]

On Wed, Jun 06, 2018 at 11:26:55AM +0200, Martin Wilck wrote:
> On Tue, 2018-06-05 at 17:40 -0500, Benjamin Marzinski wrote:
> > If a path was blacklisted, pathvec could exist but have no path in
> > it.
> > print_cmd_valid wasn't checking this before calling
> > find_multipaths_check_timeout(). This was causing it to dereference a
> > NULL pointer in these cases.
> > 
> > Cc: Martin Wilck <mwilck at suse.com>
> > Signed-off-by: Benjamin Marzinski <bmarzins at redhat.com>
> > ---
> >  multipath/main.c | 4 +---
> >  1 file changed, 1 insertion(+), 3 deletions(-)
> > 
> > diff --git a/multipath/main.c b/multipath/main.c
> > index c69e996..3f0a6aa 100644
> > --- a/multipath/main.c
> > +++ b/multipath/main.c
> > @@ -482,10 +482,8 @@ static int print_cmd_valid(int k, const vector
> > pathvec,
> >  			pp, pp->find_multipaths_timeout, &until);
> >  		if (wait != FIND_MULTIPATHS_WAITING)
> >  			k = 1;
> > -	} else if (pathvec != NULL) {
> > -		pp = VECTOR_SLOT(pathvec, 0);
> > +	} else if (pathvec != NULL && (pp = VECTOR_SLOT(pathvec,
> > 0)))
> >  		wait = find_multipaths_check_timeout(pp, 0, &until);
> > -	}
> >  	if (wait == FIND_MULTIPATHS_WAITING)
> >  		printf("FIND_MULTIPATHS_WAIT_UNTIL=\"%ld.%06ld\"\n",
> >  			       until.tv_sec, until.tv_nsec/1000);
> 
> Thanks for pointing this out. This must be the case where get_refwwid()
> fails on the path early in configure(), correct?

Yep.

-Ben

> 
> Anyway:
> Reviewed-by: Martin Wilck <mwilck at suse.com>
> 
> -- 
> Dr. Martin Wilck <mwilck at suse.com>, Tel. +49 (0)911 74053 2107
> SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton
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