From: Fedor Pchelkin <pchelkin@xxxxxxxxx>
[ Upstream commit 0c0cf3db83f8c7c9bb141c2771a34043bcf952ef ]
Inside macsec_add_dev() we free percpu macsec->secy.tx_sc.stats and
macsec->stats on some of the memory allocation failure paths. However, the
net_device is already registered to that moment: in macsec_newlink(), just
before calling macsec_add_dev(). This means that during unregister process
its priv_destructor - macsec_free_netdev() - will be called and will free
the stats again.
Remove freeing percpu stats inside macsec_add_dev() because
macsec_free_netdev() will correctly free the already allocated ones. The
pointers to unallocated stats stay NULL, and free_percpu() treats that
correctly.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Fixes: 0a28bfd4971f ("net/macsec: Add MACsec skb_metadata_dst Tx Data path support")
Fixes: c09440f7dcb3 ("macsec: introduce IEEE 802.1AE driver")
Signed-off-by: Fedor Pchelkin <pchelkin@xxxxxxxxx>
Reviewed-by: Sabrina Dubroca <sd@xxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/macsec.c | 12 +++++-------
1 file changed, 5 insertions(+), 7 deletions(-)
diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c
index 038a787943927..983cabf9a0f67 100644
--- a/drivers/net/macsec.c
+++ b/drivers/net/macsec.c
@@ -3981,17 +3981,15 @@ static int macsec_add_dev(struct net_device *dev, sci_t sci, u8 icv_len)
return -ENOMEM;
secy->tx_sc.stats = netdev_alloc_pcpu_stats(struct pcpu_tx_sc_stats);
- if (!secy->tx_sc.stats) {
- free_percpu(macsec->stats);
+ if (!secy->tx_sc.stats)
return -ENOMEM;
- }
secy->tx_sc.md_dst = metadata_dst_alloc(0, METADATA_MACSEC, GFP_KERNEL);
- if (!secy->tx_sc.md_dst) {
- free_percpu(secy->tx_sc.stats);
- free_percpu(macsec->stats);
+ if (!secy->tx_sc.md_dst)
+ /* macsec and secy percpu stats will be freed when unregistering
+ * net_device in macsec_free_netdev()
+ */
return -ENOMEM;
- }
if (sci == MACSEC_UNDEF_SCI)
sci = dev_to_sci(dev, MACSEC_PORT_ES);
--
2.39.2
