[dm-devel] [PATCH v2 40/42] libmultipath: free_multipath(): remove mpp references

[Benjamin Marzinski]

On Wed, Aug 12, 2020 at 01:34:04PM +0200, mwilck at suse.com wrote:
> From: Martin Wilck <mwilck at suse.com>
> 
> If free_paths is false, make sure no references to the dropped
> multipath remain. Otherwise multipathd may crash later when
> trying to access these.
> 
Reviewed-by: Benjamin Marzinski <bmarzins at redhat.com>
> Signed-off-by: Martin Wilck <mwilck at suse.com>
> ---
>  libmultipath/structs.c | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/libmultipath/structs.c b/libmultipath/structs.c
> index da898b7..d227ec0 100644
> --- a/libmultipath/structs.c
> +++ b/libmultipath/structs.c
> @@ -258,6 +258,21 @@ free_multipath (struct multipath * mpp, enum free_path_mode free_paths)
>  		mpp->dmi = NULL;
>  	}
>  
> +	if (!free_paths && mpp->pg) {
> +		struct pathgroup *pgp;
> +		struct path *pp;
> +		int i, j;
> +
> +		/*
> +		 * Make sure paths carry no reference to this mpp any more
> +		 */
> +		vector_foreach_slot(mpp->pg, pgp, i) {
> +			vector_foreach_slot(pgp->paths, pp, j)
> +				if (pp->mpp == mpp)
> +					pp->mpp = NULL;
> +		}
> +	}
> +
>  	free_pathvec(mpp->paths, free_paths);
>  	free_pgvec(mpp->pg, free_paths);
>  	FREE_PTR(mpp->mpcontext);
> -- 
> 2.28.0