diff options
| author | Fedor Pchelkin <pchelkin@ispras.ru> | 2023-06-13 21:22:20 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2023-06-15 12:41:01 +0200 |
| commit | 0c0cf3db83f8c7c9bb141c2771a34043bcf952ef (patch) | |
| tree | b42a85ec86993959f8beef2318548b2b242a97aa | |
| parent | net: lapbether: only support ethernet devices (diff) | |
| download | linux-0c0cf3db83f8c7c9bb141c2771a34043bcf952ef.tar.xz linux-0c0cf3db83f8c7c9bb141c2771a34043bcf952ef.zip | |
net: macsec: fix double free of percpu stats
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@ispras.ru>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | drivers/net/macsec.c | 12 |
1 files changed, 5 insertions, 7 deletions
diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c index 3427993f94f7..984dfa5d6c11 100644 --- a/drivers/net/macsec.c +++ b/drivers/net/macsec.c @@ -3997,17 +3997,15 @@ 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); |