Description

In the Linux kernel, the following vulnerability has been resolved:

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:

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

Allocated by ta...

Classification

CVE ID: CVE-2024-50261

CVSS Base Severity: LOW

CVSS Base Score: 0.0

Affected Products

Vendor: Linux

Product: Linux

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.04% (probability of being exploited)

EPSS Percentile: 5.08% (scored less or equal to compared to others)

EPSS Date: 2025-02-04 (when was this score calculated)

References

https://git.kernel.org/stable/c/872932cf75cf859804370a265dd58118129386fa
https://git.kernel.org/stable/c/9f5ae743dbe9a2458540a7d35fff0f990df025cf
https://git.kernel.org/stable/c/4614640f1d5c93c22272117dc256e9940ccac8e8
https://git.kernel.org/stable/c/f1e54d11b210b53d418ff1476c6b58a2f434dfc0

Timeline