[Cluster-devel] [PATCH] gfs2_grow: Fix gfs2_grow when only one RG is present

[Carlos Maiolino <cmaiolino@redhat.com>]

If there is only one RG in the filesystem
gfs2_grow will make a subtraction using a
null pointer to check the RG size returning
a invalide RG size value.
This patch avoid this substraction if there is
only one RG in the filesystem.
---
 gfs2/mkfs/main_grow.c |    6 +++++-
 1 files changed, 5 insertions(+), 1 deletions(-)

diff --git a/gfs2/mkfs/main_grow.c b/gfs2/mkfs/main_grow.c
index 0eca396..d7a81a3 100644
--- a/gfs2/mkfs/main_grow.c
+++ b/gfs2/mkfs/main_grow.c
@@ -133,7 +133,11 @@ static void figure_out_rgsize(struct gfs2_sbd *sdp, unsigned int *orgsize)
 	r1 = osi_list_entry(head->next->next, struct rgrp_list, list);
 	r2 = osi_list_entry(head->next->next->next, struct rgrp_list, list);
 
-	*orgsize = r2->ri.ri_addr - r1->ri.ri_addr;
+	if(r2->ri.ri_addr){
+		*orgsize = r2->ri.ri_addr - r1->ri.ri_addr;
+	}else{
+		*orgsize = r1->ri.ri_addr;
+	}
 }
 
 /**
-- 
1.7.5.2