6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Jianbo Liu <jianbol@xxxxxxxxxx>
[ Upstream commit f1e54d11b210b53d418ff1476c6b58a2f434dfc0 ]
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: 0a28bfd4971f ("net/macsec: Add MACsec skb_metadata_dst Tx Data path support")
Signed-off-by: Jianbo Liu <jianbol@xxxxxxxxxx>
Reviewed-by: Patrisious Haddad <phaddad@xxxxxxxxxx>
Reviewed-by: Chris Mi <cmi@xxxxxxxxxx>
Signed-off-by: Tariq Toukan <tariqt@xxxxxxxxxx>
Reviewed-by: Simon Horman <horms@xxxxxxxxxx>
Reviewed-by: Sabrina Dubroca <sd@xxxxxxxxxxxxxxx>
Link: https://patch.msgid.link/20241021100309.234125-1-tariqt@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/macsec.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c
index 2ada8baf815b1..7c96493a367bf 100644
--- a/drivers/net/macsec.c
+++ b/drivers/net/macsec.c
@@ -3715,8 +3715,7 @@ 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);
--
2.43.0
