genetlink: Fix off-by-one in genl_allocate_reserve_groups()

davem330 · davem330 · commit b8e429a2feac · 2016-01-13T10:28:06.000-05:00
The bug fix for adding n_groups to the computation forgot
to adjust "&gt;=" to "&gt;" to keep the condition correct.

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
@@ -185,7 +185,7 @@ static int genl_allocate_reserve_groups(int n_groups, int *first_id)
 			}
 		}
 
-		if (id + n_groups >= mc_groups_longs * BITS_PER_LONG) {
+		if (id + n_groups > mc_groups_longs * BITS_PER_LONG) {
 			unsigned long new_longs = mc_groups_longs +
 						  BITS_TO_LONGS(n_groups);
 			size_t nlen = new_longs * sizeof(unsigned long);

Original file line number	Diff line number	Diff line change
`@@ -185,7 +185,7 @@ static int genl_allocate_reserve_groups(int n_groups, int *first_id)`
`185`	`185`	`}`
`186`	`186`	`}`
`187`	`187`
`188`		`- if (id + n_groups >= mc_groups_longs * BITS_PER_LONG) {`
	`188`	`+ if (id + n_groups > mc_groups_longs * BITS_PER_LONG) {`
`189`	`189`	`unsigned long new_longs = mc_groups_longs +`
`190`	`190`	`BITS_TO_LONGS(n_groups);`
`191`	`191`	`size_t nlen = new_longs * sizeof(unsigned long);`