2022-08-01 14:29:29

by Wen Gong

[permalink] [raw]
Subject: [PATCH v2] 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:
<6>[21705.888627] wlan0: deauthenticating from d0:76:8f:82:be:75 by local choice (Reason: 3=DEAUTH_LEAVING)
<4>[21713.799910] ath10k_pci 0000:01:00.0: failed to delete peer d0:76:8f:82:be:75 for vdev 0: -110
<4>[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
<3>[21713.799968] ==================================================================
<3>[21713.799991] BUG: KFENCE: use-after-free read in ath10k_sta_state+0x265/0xb8a [ath10k_core]
<3>[21713.799991]
<3>[21713.799997] Use-after-free read at 0x00000000abe1c75e (in kfence-#69):
<4>[21713.800010] ath10k_sta_state+0x265/0xb8a [ath10k_core]
<4>[21713.800041] drv_sta_state+0x115/0x677 [mac80211]
<4>[21713.800059] __sta_info_destroy_part2+0xb1/0x133 [mac80211]
<4>[21713.800076] __sta_info_flush+0x11d/0x162 [mac80211]
<4>[21713.800093] ieee80211_set_disassoc+0x12d/0x2f4 [mac80211]
<4>[21713.800110] ieee80211_mgd_deauth+0x26c/0x29b [mac80211]
<4>[21713.800137] cfg80211_mlme_deauth+0x13f/0x1bb [cfg80211]
<4>[21713.800153] nl80211_deauthenticate+0xf8/0x121 [cfg80211]
<4>[21713.800161] genl_rcv_msg+0x38e/0x3be
<4>[21713.800166] netlink_rcv_skb+0x89/0xf7
<4>[21713.800171] genl_rcv+0x28/0x36
<4>[21713.800176] netlink_unicast+0x179/0x24b
<4>[21713.800181] netlink_sendmsg+0x3a0/0x40e
<4>[21713.800187] sock_sendmsg+0x72/0x76
<4>[21713.800192] ____sys_sendmsg+0x16d/0x1e3
<4>[21713.800196] ___sys_sendmsg+0x95/0xd1
<4>[21713.800200] __sys_sendmsg+0x85/0xbf
<4>[21713.800205] do_syscall_64+0x43/0x55
<4>[21713.800210] entry_SYSCALL_64_after_hwframe+0x44/0xa9
<3>[21713.800213]
<4>[21713.800219] kfence-#69: 0x000000009149b0d5-0x000000004c0697fb, size=1064, cache=kmalloc-2k
<4>[21713.800219]
<4>[21713.800224] allocated by task 13 on cpu 0 at 21705.501373s:
<4>[21713.800241] ath10k_peer_map_event+0x7e/0x154 [ath10k_core]
<4>[21713.800254] ath10k_htt_t2h_msg_handler+0x586/0x1039 [ath10k_core]
<4>[21713.800265] ath10k_htt_htc_t2h_msg_handler+0x12/0x28 [ath10k_core]
<4>[21713.800277] ath10k_htc_rx_completion_handler+0x14c/0x1b5 [ath10k_core]
<4>[21713.800283] ath10k_pci_process_rx_cb+0x195/0x1df [ath10k_pci]
<4>[21713.800294] ath10k_ce_per_engine_service+0x55/0x74 [ath10k_core]
<4>[21713.800305] ath10k_ce_per_engine_service_any+0x76/0x84 [ath10k_core]
<4>[21713.800310] ath10k_pci_napi_poll+0x49/0x144 [ath10k_pci]
<4>[21713.800316] net_rx_action+0xdc/0x361
<4>[21713.800320] __do_softirq+0x163/0x29a
<4>[21713.800325] asm_call_irq_on_stack+0x12/0x20
<4>[21713.800331] do_softirq_own_stack+0x3c/0x48
<4>[21713.800337] __irq_exit_rcu+0x9b/0x9d
<4>[21713.800342] common_interrupt+0xc9/0x14d
<4>[21713.800346] asm_common_interrupt+0x1e/0x40
<4>[21713.800351] ksoftirqd_should_run+0x5/0x16
<4>[21713.800357] smpboot_thread_fn+0x148/0x211
<4>[21713.800362] kthread+0x150/0x15f
<4>[21713.800367] ret_from_fork+0x22/0x30
<4>[21713.800370]
<4>[21713.800374] freed by task 708 on cpu 1 at 21713.799953s:
<4>[21713.800498] ath10k_sta_state+0x2c6/0xb8a [ath10k_core]
<4>[21713.800515] drv_sta_state+0x115/0x677 [mac80211]
<4>[21713.800532] __sta_info_destroy_part2+0xb1/0x133 [mac80211]
<4>[21713.800548] __sta_info_flush+0x11d/0x162 [mac80211]
<4>[21713.800565] ieee80211_set_disassoc+0x12d/0x2f4 [mac80211]
<4>[21713.800581] ieee80211_mgd_deauth+0x26c/0x29b [mac80211]
<4>[21713.800598] cfg80211_mlme_deauth+0x13f/0x1bb [cfg80211]
<4>[21713.800614] nl80211_deauthenticate+0xf8/0x121 [cfg80211]
<4>[21713.800619] genl_rcv_msg+0x38e/0x3be
<4>[21713.800623] netlink_rcv_skb+0x89/0xf7
<4>[21713.800628] genl_rcv+0x28/0x36
<4>[21713.800632] netlink_unicast+0x179/0x24b
<4>[21713.800637] netlink_sendmsg+0x3a0/0x40e
<4>[21713.800642] sock_sendmsg+0x72/0x76
<4>[21713.800646] ____sys_sendmsg+0x16d/0x1e3
<4>[21713.800651] ___sys_sendmsg+0x95/0xd1
<4>[21713.800655] __sys_sendmsg+0x85/0xbf
<4>[21713.800659] do_syscall_64+0x43/0x55
<4>[21713.800663] entry_SYSCALL_64_after_hwframe+0x44/0xa9

Tested-on: QCA6174 hw3.2 PCI WLAN.RM.4.4.1-00288-QCARMSWPZ-1

Fixes: d0eeafad1189 ("ath10k: Clean up peer when sta goes away.")
Signed-off-by: Wen Gong <[email protected]>
---
v2: add "wifi:" in subject

drivers/net/wireless/ath/ath10k/mac.c | 54 ++++++++++++++-------------
1 file changed, 29 insertions(+), 25 deletions(-)

diff --git a/drivers/net/wireless/ath/ath10k/mac.c b/drivers/net/wireless/ath/ath10k/mac.c
index a04e18250dae..5ccbb81739de 100644
--- a/drivers/net/wireless/ath/ath10k/mac.c
+++ b/drivers/net/wireless/ath/ath10k/mac.c
@@ -864,11 +864,36 @@ static int ath10k_peer_delete(struct ath10k *ar, u32 vdev_id, const u8 *addr)
return 0;
}

+static void ath10k_peer_map_cleanup(struct ath10k *ar, struct ath10k_peer *peer)
+{
+ int peer_id, i;
+
+ lockdep_assert_held(&ar->conf_mutex);
+
+ for_each_set_bit(peer_id, peer->peer_ids,
+ ATH10K_MAX_NUM_PEER_IDS) {
+ ar->peer_map[peer_id] = NULL;
+ }
+
+ /* Double check that peer is properly un-referenced from
+ * the peer_map
+ */
+ for (i = 0; i < ARRAY_SIZE(ar->peer_map); i++) {
+ if (ar->peer_map[i] == peer) {
+ ath10k_warn(ar, "removing stale peer_map entry for %pM (ptr %pK idx %d)\n",
+ peer->addr, peer, i);
+ ar->peer_map[i] = NULL;
+ }
+ }
+
+ list_del(&peer->list);
+ kfree(peer);
+ ar->num_peers--;
+}
+
static void ath10k_peer_cleanup(struct ath10k *ar, u32 vdev_id)
{
struct ath10k_peer *peer, *tmp;
- int peer_id;
- int i;

lockdep_assert_held(&ar->conf_mutex);

@@ -880,25 +905,7 @@ static void ath10k_peer_cleanup(struct ath10k *ar, u32 vdev_id)
ath10k_warn(ar, "removing stale peer %pM from vdev_id %d\n",
peer->addr, vdev_id);

- for_each_set_bit(peer_id, peer->peer_ids,
- ATH10K_MAX_NUM_PEER_IDS) {
- ar->peer_map[peer_id] = NULL;
- }
-
- /* Double check that peer is properly un-referenced from
- * the peer_map
- */
- for (i = 0; i < ARRAY_SIZE(ar->peer_map); i++) {
- if (ar->peer_map[i] == peer) {
- ath10k_warn(ar, "removing stale peer_map entry for %pM (ptr %pK idx %d)\n",
- peer->addr, peer, i);
- ar->peer_map[i] = NULL;
- }
- }
-
- list_del(&peer->list);
- kfree(peer);
- ar->num_peers--;
+ ath10k_peer_map_cleanup(ar, peer);
}
spin_unlock_bh(&ar->data_lock);
}
@@ -7620,10 +7627,7 @@ static int ath10k_sta_state(struct ieee80211_hw *hw,
/* Clean up the peer object as well since we
* must have failed to do this above.
*/
- list_del(&peer->list);
- ar->peer_map[i] = NULL;
- kfree(peer);
- ar->num_peers--;
+ ath10k_peer_map_cleanup(ar, peer);
}
}
spin_unlock_bh(&ar->data_lock);

base-commit: c35538ce3b892dd4b41e24e887a434f296792959
--
2.31.1



2022-08-02 06:58:46

by Kalle Valo

[permalink] [raw]
Subject: Re: [PATCH v2] wifi: ath10k: add peer map clean up for peer delete in ath10k_sta_state()

Wen Gong <[email protected]> writes:

> 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:
> <6>[21705.888627] wlan0: deauthenticating from d0:76:8f:82:be:75 by local choice (Reason: 3=DEAUTH_LEAVING)
> <4>[21713.799910] ath10k_pci 0000:01:00.0: failed to delete peer d0:76:8f:82:be:75 for vdev 0: -110
> <4>[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
> <3>[21713.799968] ==================================================================
> <3>[21713.799991] BUG: KFENCE: use-after-free read in ath10k_sta_state+0x265/0xb8a [ath10k_core]
> <3>[21713.799991]

In the pending branch I removed the log level numbers, they just make
the commit log harder to read.

--
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https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches