Hold rcu_read_lock in netdev_nl_napi_get_doit, which calls napi_by_id
and is required to be called under rcu_read_lock.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 27f91aaf49b3 ("netdev-genl: Add netlink framework functions for napi")
Signed-off-by: Joe Damato <jdamato@xxxxxxxxxx>
---
net/core/netdev-genl.c | 27 +++++++++++++++++++++------
1 file changed, 21 insertions(+), 6 deletions(-)
diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c
index 765ce7c9d73b..934c63a93524 100644
--- a/net/core/netdev-genl.c
+++ b/net/core/netdev-genl.c
@@ -216,6 +216,23 @@ netdev_nl_napi_fill_one(struct sk_buff *rsp, struct napi_struct *napi,
return -EMSGSIZE;
}
+/* must be called under rcu_read_lock(), because napi_by_id requires it */
+static struct napi_struct *__do_napi_by_id(unsigned int napi_id,
+ struct genl_info *info, int *err)
+{
+ struct napi_struct *napi;
+
+ napi = napi_by_id(napi_id);
+ if (napi) {
+ *err = 0;
+ } else {
+ NL_SET_BAD_ATTR(info->extack, info->attrs[NETDEV_A_NAPI_ID]);
+ *err = -ENOENT;
+ }
+
+ return napi;
+}
+
int netdev_nl_napi_get_doit(struct sk_buff *skb, struct genl_info *info)
{
struct napi_struct *napi;
@@ -233,15 +250,13 @@ int netdev_nl_napi_get_doit(struct sk_buff *skb, struct genl_info *info)
return -ENOMEM;
rtnl_lock();
+ rcu_read_lock();
- napi = napi_by_id(napi_id);
- if (napi) {
+ napi = __do_napi_by_id(napi_id, info, &err);
+ if (!err)
err = netdev_nl_napi_fill_one(rsp, napi, info);
- } else {
- NL_SET_BAD_ATTR(info->extack, info->attrs[NETDEV_A_NAPI_ID]);
- err = -ENOENT;
- }
+ rcu_read_unlock();
rtnl_unlock();
if (err)
--
2.25.1
