From: WANG Cong <xiyou.wangcong@xxxxxxxxx>
[ Upstream commit 5778d39d070b4ac5f889928175b7f2d53ae7504e ]
We dynamically allocate divisor+1 entries for ->ht[] in tc_u_hnode:
ht = kzalloc(sizeof(*ht) + divisor*sizeof(void *), GFP_KERNEL);
So ->ht is supposed to be the last field of this struct, however
this is broken, since an rcu head is appended after it.
Fixes: 1ce87720d456 ("net: sched: make cls_u32 lockless")
Cc: Jamal Hadi Salim <jhs@xxxxxxxxxxxx>
Cc: John Fastabend <john.fastabend@xxxxxxxxx>
Signed-off-by: Cong Wang <xiyou.wangcong@xxxxxxxxx>
Acked-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sasha.levin@xxxxxxxxxx>
---
net/sched/cls_u32.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/net/sched/cls_u32.c b/net/sched/cls_u32.c
index 0472909..b78d81f 100644
--- a/net/sched/cls_u32.c
+++ b/net/sched/cls_u32.c
@@ -78,8 +78,11 @@ struct tc_u_hnode {
struct tc_u_common *tp_c;
int refcnt;
unsigned int divisor;
- struct tc_u_knode __rcu *ht[1];
struct rcu_head rcu;
+ /* The 'ht' field MUST be the last field in structure to allow for
+ * more entries allocated at end of structure.
+ */
+ struct tc_u_knode __rcu *ht[1];
};
struct tc_u_common {
--
2.1.0
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html