Merge: CVE-2024-50261: macsec: Fix use-after-free while sending the offloading packet

MR: https://gitlab.com/redhat/centos-stream/src/kernel/centos-stream-9/-/merge_requests/5752

JIRA: https://issues.redhat.com/browse/RHEL-66910
CVE: CVE-2024-50261

```
macsec: Fix use-after-free while sending the offloading packet

KASAN reports the following UAF. The metadata_dst, which is used to
store the SCI value for macsec offload, is already freed by
metadata_dst_free() in macsec_free_netdev(), while driver still use it
for sending the packet.

To fix this issue, dst_release() is used instead to release
metadata_dst. So it is not freed instantly in macsec_free_netdev() if
still referenced by skb.

 BUG: KASAN: slab-use-after-free in mlx5e_xmit+0x1e8f/0x4190 [mlx5_core]
 Read of size 2 at addr ffff88813e42e038 by task kworker/7:2/714
 [...]
 Workqueue: mld mld_ifc_work
 Call Trace:
  <TASK>
  dump_stack_lvl+0x51/0x60
  print_report+0xc1/0x600
  kasan_report+0xab/0xe0
  mlx5e_xmit+0x1e8f/0x4190 [mlx5_core]
  dev_hard_start_xmit+0x120/0x530
  sch_direct_xmit+0x149/0x11e0
  __qdisc_run+0x3ad/0x1730
  __dev_queue_xmit+0x1196/0x2ed0
  vlan_dev_hard_start_xmit+0x32e/0x510 [8021q]
  dev_hard_start_xmit+0x120/0x530
  __dev_queue_xmit+0x14a7/0x2ed0
  macsec_start_xmit+0x13e9/0x2340
  dev_hard_start_xmit+0x120/0x530
  __dev_queue_xmit+0x14a7/0x2ed0
  ip6_finish_output2+0x923/0x1a70
  ip6_finish_output+0x2d7/0x970
  ip6_output+0x1ce/0x3a0
  NF_HOOK.constprop.0+0x15f/0x190
  mld_sendpack+0x59a/0xbd0
  mld_ifc_work+0x48a/0xa80
  process_one_work+0x5aa/0xe50
  worker_thread+0x79c/0x1290
  kthread+0x28f/0x350
  ret_from_fork+0x2d/0x70
  ret_from_fork_asm+0x11/0x20
  </TASK>

 Allocated by task 3922:
  kasan_save_stack+0x20/0x40
  kasan_save_track+0x10/0x30
  __kasan_kmalloc+0x77/0x90
  __kmalloc_noprof+0x188/0x400
  metadata_dst_alloc+0x1f/0x4e0
  macsec_newlink+0x914/0x1410
  __rtnl_newlink+0xe08/0x15b0
  rtnl_newlink+0x5f/0x90
  rtnetlink_rcv_msg+0x667/0xa80
  netlink_rcv_skb+0x12c/0x360
  netlink_unicast+0x551/0x770
  netlink_sendmsg+0x72d/0xbd0
  __sock_sendmsg+0xc5/0x190
  ____sys_sendmsg+0x52e/0x6a0
  ___sys_sendmsg+0xeb/0x170
  __sys_sendmsg+0xb5/0x140
  do_syscall_64+0x4c/0x100
  entry_SYSCALL_64_after_hwframe+0x4b/0x53

 Freed by task 4011:
  kasan_save_stack+0x20/0x40
  kasan_save_track+0x10/0x30
  kasan_save_free_info+0x37/0x50
  poison_slab_object+0x10c/0x190
  __kasan_slab_free+0x11/0x30
  kfree+0xe0/0x290
  macsec_free_netdev+0x3f/0x140
  netdev_run_todo+0x450/0xc70
  rtnetlink_rcv_msg+0x66f/0xa80
  netlink_rcv_skb+0x12c/0x360
  netlink_unicast+0x551/0x770
  netlink_sendmsg+0x72d/0xbd0
  __sock_sendmsg+0xc5/0x190
  ____sys_sendmsg+0x52e/0x6a0
  ___sys_sendmsg+0xeb/0x170
  __sys_sendmsg+0xb5/0x140
  do_syscall_64+0x4c/0x100
  entry_SYSCALL_64_after_hwframe+0x4b/0x53

Fixes: 0a28bfd ("net/macsec: Add MACsec skb_metadata_dst Tx Data path support")
Signed-off-by: Jianbo Liu <jianbol@nvidia.com>
Reviewed-by: Patrisious Haddad <phaddad@nvidia.com>
Reviewed-by: Chris Mi <cmi@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://patch.msgid.link/20241021100309.234125-1-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
(cherry picked from commit f1e54d1)
```

Signed-off-by: CKI Backport Bot <cki-ci-bot+cki-gitlab-backport-bot@redhat.com>

---

<small>Created 2024-11-11 07:25 UTC by backporter - [KWF FAQ](https://red.ht/kernel_workflow_doc) - [Slack #team-kernel-workflow](https://redhat-internal.slack.com/archives/C04LRUPMJQ5) - [Source](https://gitlab.com/cki-project/kernel-workflow/-/blob/main/webhook/utils/backporter.py) - [Documentation](https://gitlab.com/cki-project/kernel-workflow/-/blob/main/docs/README.backporter.md) - [Report an issue](https://gitlab.com/cki-project/kernel-workflow/-/issues/new?issue%5Btitle%5D=backporter%20webhook%20issue)</small>

Approved-by: Antoine Tenart <atenart@redhat.com>
Approved-by: Hangbin Liu <haliu@redhat.com>
Approved-by: CKI KWF Bot <cki-ci-bot+kwf-gitlab-com@redhat.com>

Merged-by: Rado Vrbovsky <rvrbovsk@redhat.com>

Author: emmil

drivers/net/macsec.c

@@ -3747,8 +3747,7 @@ static void macsec_free_netdev(struct net_device *dev)
 {
 	struct macsec_dev *macsec = macsec_priv(dev);
 
-	if (macsec->secy.tx_sc.md_dst)
-		metadata_dst_free(macsec->secy.tx_sc.md_dst);
+	dst_release(&macsec->secy.tx_sc.md_dst->dst);
 	free_percpu(macsec->stats);
 	free_percpu(macsec->secy.tx_sc.stats);