diff options
| author | Xin Long <lucien.xin@gmail.com> | 2019-09-23 17:02:46 +0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-09-26 09:25:03 +0200 |
| commit | ba56d8ce38c8252fff5b745db3899cf092578ede (patch) | |
| tree | 183a59a56a2475a55570eff85e7b4501f04aff17 /drivers | |
| parent | 2dbf45d13539038aa17ba02df0bb206825b2f403 (diff) | |
macsec: drop skb sk before calling gro_cells_receive
Fei Liu reported a crash when doing netperf on a topo of macsec
dev over veth:
[ 448.919128] refcount_t: underflow; use-after-free.
[ 449.090460] Call trace:
[ 449.092895] refcount_sub_and_test+0xb4/0xc0
[ 449.097155] tcp_wfree+0x2c/0x150
[ 449.100460] ip_rcv+0x1d4/0x3a8
[ 449.103591] __netif_receive_skb_core+0x554/0xae0
[ 449.108282] __netif_receive_skb+0x28/0x78
[ 449.112366] netif_receive_skb_internal+0x54/0x100
[ 449.117144] napi_gro_complete+0x70/0xc0
[ 449.121054] napi_gro_flush+0x6c/0x90
[ 449.124703] napi_complete_done+0x50/0x130
[ 449.128788] gro_cell_poll+0x8c/0xa8
[ 449.132351] net_rx_action+0x16c/0x3f8
[ 449.136088] __do_softirq+0x128/0x320
The issue was caused by skb's true_size changed without its sk's
sk_wmem_alloc increased in tcp/skb_gro_receive(). Later when the
skb is being freed and the skb's truesize is subtracted from its
sk's sk_wmem_alloc in tcp_wfree(), underflow occurs.
macsec is calling gro_cells_receive() to receive a packet, which
actually requires skb->sk to be NULL. However when macsec dev is
over veth, it's possible the skb->sk is still set if the skb was
not unshared or expanded from the peer veth.
ip_rcv() is calling skb_orphan() to drop the skb's sk for tproxy,
but it is too late for macsec's calling gro_cells_receive(). So
fix it by dropping the skb's sk earlier on rx path of macsec.
Fixes: 5491e7c6b1a9 ("macsec: enable GRO and RPS on macsec devices")
Reported-by: Xiumei Mu <xmu@redhat.com>
Reported-by: Fei Liu <feliu@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/net/macsec.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c index 8f46aa1ddec0..cb7637364b40 100644 --- a/drivers/net/macsec.c +++ b/drivers/net/macsec.c @@ -1235,6 +1235,7 @@ deliver: macsec_rxsa_put(rx_sa); macsec_rxsc_put(rx_sc); + skb_orphan(skb); ret = gro_cells_receive(&macsec->gro_cells, skb); if (ret == NET_RX_SUCCESS) count_rx(dev, skb->len); |