From: Nikolay Aleksandrov nikolay@nvidia.com
stable inclusion from stable-v5.10.96 commit 9ffc94a81b0f2b7db78a630b5ae1032a551619d6 bugzilla: https://gitee.com/openeuler/kernel/issues/I55NWB
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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[ Upstream commit dcb2c5c6ca9b9177f04abaf76e5a983d177c9414 ]
When dumping vlan options for a single net device we send the same entries infinitely because user-space expects a 0 return at the end but we keep returning skb->len and restarting the dump on retry. Fix it by returning the value from br_vlan_dump_dev() if it completed or there was an error. The only case that must return skb->len is when the dump was incomplete and needs to continue (-EMSGSIZE).
Reported-by: Benjamin Poirier bpoirier@nvidia.com Fixes: 8dcea187088b ("net: bridge: vlan: add rtm definitions and dump support") Signed-off-by: Nikolay Aleksandrov nikolay@nvidia.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yu Liao liaoyu15@huawei.com Reviewed-by: Wei Li liwei391@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- net/bridge/br_vlan.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/net/bridge/br_vlan.c b/net/bridge/br_vlan.c index 08c77418c687..1f508d998fb2 100644 --- a/net/bridge/br_vlan.c +++ b/net/bridge/br_vlan.c @@ -1873,7 +1873,8 @@ static int br_vlan_rtm_dump(struct sk_buff *skb, struct netlink_callback *cb) goto out_err; } err = br_vlan_dump_dev(dev, skb, cb, dump_flags); - if (err && err != -EMSGSIZE) + /* if the dump completed without an error we return 0 here */ + if (err != -EMSGSIZE) goto out_err; } else { for_each_netdev_rcu(net, dev) {