CVE-2022-49328 mt76: fix use-after-free by removing a non-RCU wcid pointer
A use-after-free vulnerability in the mt76 Wi-Fi driver allows attackers to cause a system crash or potentially execute arbitrary code.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2022-49328?
CVE-2022-49328 is a high-severity use after free vulnerability in Linux kernel, published on 26 Feb 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
mt76: fix use-after-free by removing a non-RCU wcid pointer
Fixes an issue caught by KASAN about use-after-free in mt76_txq_schedule by protecting mtxq->wcid with rcu_lock between mt76_txq_schedule and sta_info_[alloc, free].
[18853.876689] ================================================================== [18853.876751] BUG: KASAN: use-after-free in mt76_txq_schedule+0x204/0xaf8 [mt76] [18853.876773] Read of size 8 at addr ffffffaf989a2138 by task mt76-tx phy0/883 [18853.876786] [18853.876810] CPU: 5 PID: 883 Comm: mt76-tx phy0 Not tainted 5.10.100-fix-510-56778d365941-kasan #5 0b01fbbcf41a530f52043508fec2e31a4215
[18853.876840] Call trace: [18853.876861] dump_backtrace+0x0/0x3ec [18853.876878] show_stack+0x20/0x2c [18853.876899] dump_stack+0x11c/0x1ac [18853.876918] print_address_description+0x74/0x514 [18853.876934] kasan_report+0x134/0x174 [18853.876948] __asan_report_load8_noabort+0x44/0x50 [18853.876976] mt76_txq_schedule+0x204/0xaf8 [mt76 074e03e4640e97fe7405ee1fab547b81c4fa45d2] [18853.877002] mt76_txq_schedule_all+0x2c/0x48 [mt76 074e03e4640e97fe7405ee1fab547b81c4fa45d2] [18853.877030] mt7921_tx_worker+0xa0/0x1cc [mt7921_common f0875ebac9d7b4754e1010549e7db50fbd90a047] [18853.877054] __mt76_worker_fn+0x190/0x22c [mt76 074e03e4640e97fe7405ee1fab547b81c4fa45d2] [18853.877071] kthread+0x2f8/0x3b8 [18853.877087] ret_from_fork+0x10/0x30 [18853.877098] [18853.877112] Allocated by task 941: [18853.877131] kasan_save_stack+0x38/0x68 [18853.877147] __kasan_kmalloc+0xd4/0xfc [18853.877163] kasan_kmalloc+0x10/0x1c [18853.877177] __kmalloc+0x264/0x3c4 [18853.877294] sta_info_alloc+0x460/0xf88 [mac80211] [18853.877410] ieee80211_prep_connection+0x204/0x1ee0 [mac80211] [18853.877523] ieee80211_mgd_auth+0x6c4/0xa4c [mac80211] [18853.877635] ieee80211_auth+0x20/0x2c [mac80211] [18853.877733] rdev_auth+0x7c/0x438 [cfg80211] [18853.877826] cfg80211_mlme_auth+0x26c/0x390 [cfg80211] [18853.877919] nl80211_authenticate+0x6d4/0x904 [cfg80211] [18853.877938] genl_rcv_msg+0x748/0x93c [18853.877954] netlink_rcv_skb+0x160/0x2a8 [18853.877969] genl_rcv+0x3c/0x54 [18853.877985] netlink_unicast_kernel+0x104/0x1ec [18853.877999] netlink_unicast+0x178/0x268 [18853.878015] netlink_sendmsg+0x3cc/0x5f0 [18853.878030] sock_sendmsg+0xb4/0xd8 [18853.878043] ____sys_sendmsg+0x2f8/0x53c [18853.878058] ___sys_sendmsg+0xe8/0x150 [18853.878071] __sys_sendmsg+0xc4/0x1f4 [18853.878087] __arm64_compat_sys_sendmsg+0x88/0x9c [18853.878101] el0_svc_common+0x1b4/0x390 [18853.878115] do_el0_svc_compat+0x8c/0xdc [18853.878131] el0_svc_compat+0x10/0x1c [18853.878146] el0_sync_compat_handler+0xa8/0xcc [18853.878161] el0_sync_compat+0x188/0x1c0 [18853.878171] [18853.878183] Freed by task 10927: [18853.878200] kasan_save_stack+0x38/0x68 [18853.878215] kasan_set_track+0x28/0x3c [18853.878228] kasan_set_free_info+0x24/0x48 [18853.878244] __kasan_slab_free+0x11c/0x154 [18853.878259] kasan_slab_free+0x14/0x24 [18853.878273] slab_free_freelist_hook+0xac/0x1b0 [18853.878287] kfree+0x104/0x390 [18853.878402] sta_info_free+0x198/0x210 [mac80211] [18853.878515] __sta_info_destroy_part2+0x230/0x2d4 [mac80211] [18853.878628] __sta_info_flush+0x300/0x37c [mac80211] [18853.878740] ieee80211_set_disassoc+0x2cc/0xa7c [mac80211] [18853.878851] ieee80211_mgd_deauth+0x4a4/0x10a0 [mac80211] [18853.878962] ieee80211_deauth+0x20/0x2c [mac80211] [18853.879057] rdev_deauth+0x7c/0x438 [cfg80211] [18853.879150] cfg80211_mlme_deauth+0x274/0x414 [cfg80211] [18853.879243] cfg80211_mlme_down+0xe4/0x118 [cfg80211] [18853.879335] cfg80211_disconnect+0x218/0x2d8 [cfg80211] [18853.879427] __cfg80211_leave+0x17c/0x240 [cfg80211] [18853.879519] cfg80211_leave+0x3c/0x58 [cfg80211] [18853.879611] wiphy_suspend+0xdc/0x200 [cfg80211] [18853.879628] dpm_run_callback+0x58/0x408 [18853.879642] __device_suspend+0x4cc/0x864 [18853.879658] async_suspend+0x34/0xf4 [18 ---truncated---
Weakness: CWE-416
Which versions are affected by CVE-2022-49328?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2022-49328?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2022-49328 being exploited?
There is no known exploitation of CVE-2022-49328 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2022-49328, GHSA-v93h-9m65-mhx5, ROOT-OS-DEBIAN-11-CVE-2022-49328, UBUNTU-CVE-2022-49328.