# \[PATCH net\] hv\_netvsc: Reset the RSC count if NVSP\_STAT\_FAIL in netvsc\_receive() - From: Andrea Parri (Microsoft) \ - Date: 2021-02-03 11:37:28 - List: netdev - Page: https://ratatoskr.run/netdev/2021/02/6256909 - Thread: https://ratatoskr.run/linux-hyperv/2021/02/6256909/t.md ```text Commit 44144185951a0f ("hv_netvsc: Add validation for untrusted Hyper-V values") added validation to rndis_filter_receive_data() (and rndis_filter_receive()) which introduced NVSP_STAT_FAIL-scenarios where the count is not updated/reset. Fix this omission, and prevent similar scenarios from occurring in the future. Reported-by: Juan Vazquez Signed-off-by: Andrea Parri (Microsoft) Cc: "David S. Miller" Cc: Jakub Kicinski Cc: Fixes: 44144185951a0f ("hv_netvsc: Add validation for untrusted Hyper-V values") --- drivers/net/hyperv/netvsc.c | 5 ++++- drivers/net/hyperv/rndis_filter.c | 2 -- 2 files changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c index 2350342b961ff..13bd48a75db76 100644 --- a/drivers/net/hyperv/netvsc.c +++ b/drivers/net/hyperv/netvsc.c @@ -1262,8 +1262,11 @@ static int netvsc_receive(struct net_device *ndev, ret = rndis_filter_receive(ndev, net_device, nvchan, data, buflen); - if (unlikely(ret != NVSP_STAT_SUCCESS)) + if (unlikely(ret != NVSP_STAT_SUCCESS)) { + /* Drop incomplete packet */ + nvchan->rsc.cnt = 0; status = NVSP_STAT_FAIL; + } } enq_receive_complete(ndev, net_device, q_idx, diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c index 598713c0d5a87..3aab2b867fc0d 100644 --- a/drivers/net/hyperv/rndis_filter.c +++ b/drivers/net/hyperv/rndis_filter.c @@ -509,8 +509,6 @@ static int rndis_filter_receive_data(struct net_device *ndev, return ret; drop: - /* Drop incomplete packet */ - nvchan->rsc.cnt = 0; return NVSP_STAT_FAIL; } -- 2.25.1 ```