CVE-2022-50880: 
Linux Kernel vulnerability analysis and mitigation

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

wifi: ath10k: add peer map clean up for peer delete in ath10k_sta_state()

When peer delete failed in a disconnect operation, use-after-free detected by KFENCE in below log. It is because for each vdev_id and address, it has only one struct ath10k_peer, it is allocated in ath10k_peer_map_event(). When connected to an AP, it has more than one HTT_T2H_MSG_TYPE_PEER_MAP reported from firmware, then the array peer_map of struct ath10k will be set muti-elements to the same ath10k_peer in ath10k_peer_map_event(). When peer delete failed in ath10k_sta_state(), the ath10k_peer will be free for the 1st peer id in array peer_map of struct ath10k, and then use-after-free happened for the 2nd peer id because they map to the same ath10k_peer.

And clean up all peers in array peer_map for the ath10k_peer, then user-after-free disappeared

peer map event log: [ 306.911021] wlan0: authenticate with b0:2a:43:e6:75:0e [ 306.957187] ath10k_pci 0000:01:00.0: mac vdev 0 peer create b0:2a:43:e6:75:0e (new sta) sta 1 / 32 peer 1 / 33 [ 306.957395] ath10k_pci 0000:01:00.0: htt peer map vdev 0 peer b0:2a:43:e6:75:0e id 246 [ 306.957404] ath10k_pci 0000:01:00.0: htt peer map vdev 0 peer b0:2a:43:e6:75:0e id 198 [ 306.986924] ath10k_pci 0000:01:00.0: htt peer map vdev 0 peer b0:2a:43:e6:75:0e id 166

peer unmap event log: [ 435.715691] wlan0: deauthenticating from b0:2a:43:e6:75:0e by local choice (Reason: 3=DEAUTH_LEAVING) [ 435.716802] ath10k_pci 0000:01:00.0: mac vdev 0 peer delete b0:2a:43:e6:75:0e sta ffff990e0e9c2b50 (sta gone) [ 435.717177] ath10k_pci 0000:01:00.0: htt peer unmap vdev 0 peer b0:2a:43:e6:75:0e id 246 [ 435.717186] ath10k_pci 0000:01:00.0: htt peer unmap vdev 0 peer b0:2a:43:e6:75:0e id 198 [ 435.717193] ath10k_pci 0000:01:00.0: htt peer unmap vdev 0 peer b0:2a:43:e6:75:0e id 166

use-after-free log: [21705.888627] wlan0: deauthenticating from d0:76:8f:82:be:75 by local choice (Reason: 3=DEAUTH_LEAVING) [21713.799910] ath10k_pci 0000:01:00.0: failed to delete peer d0:76:8f:82:be:75 for vdev 0: -110 [21713.799925] ath10k_pci 0000:01:00.0: found sta peer d0:76:8f:82:be:75 (ptr 0000000000000000 id 102) entry on vdev 0 after it was supposedly removed [21713.799968] ================================================================== [21713.799991] BUG: KFENCE: use-after-free read in ath10k_sta_state+0x265/0xb8a [ath10k_core] [21713.799991] [21713.799997] Use-after-free read at 0x00000000abe1c75e (in kfence-#69): [21713.800010] ath10k_sta_state+0x265/0xb8a [ath10k_core] [21713.800041] drv_sta_state+0x115/0x677 [mac80211] [21713.800059] __sta_info_destroy_part2+0xb1/0x133 [mac80211] [21713.800076] __sta_info_flush+0x11d/0x162 [mac80211] [21713.800093] ieee80211_set_disassoc+0x12d/0x2f4 [mac80211] [21713.800110] ieee80211_mgd_deauth+0x26c/0x29b [mac80211] [21713.800137] cfg80211_mlme_deauth+0x13f/0x1bb [cfg80211] [21713.800153] nl80211_deauthenticate+0xf8/0x121 [cfg80211] [21713.800161] genl_rcv_msg+0x38e/0x3be [21713.800166] netlink_rcv_skb+0x89/0xf7 [21713.800171] genl_rcv+0x28/0x36 [21713.800176] netlink_unicast+0x179/0x24b [21713.800181] netlink_sendmsg+0x3a0/0x40e [21713.800187] sock_sendmsg+0x72/0x76 [21713.800192] ____sys_sendmsg+0x16d/0x1e3 [21713.800196] ___sys_sendmsg+0x95/0xd1 [21713.800200] __sys_sendmsg+0x85/0xbf [21713.800205] do_syscall_64+0x43/0x55 [21713.800210] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [21713.800213] [21713.800219] kfence-#69: 0x000000009149b0d5-0x000000004c0697fb, size=1064, cache=kmalloc-2k [21713.800219] [21713.800224] allocated by task 13 on cpu 0 at 21705.501373s: [21713.800241] ath10k_peer_map_event+0x7e/0x154 [ath10k_core] [21713.800254] ath10k_htt_t2h_msg_handler+0x586/0x1039 [ath10k_core] [21713.800265] ath10k_htt_htc_t2h_msg_handler+0x12/0x28 [ath10k_core] [21713.800277] ath10k_htc_rx_completion_handler+0x14c/0x1b5 [ath10k_core] [21713.800283] ath10k_pci_process_rx_cb+0x195/0x1d ---truncated---