The ath11k active pdevs are protected by RCU but the temperature event
handling code calling ath11k_mac_get_ar_by_pdev_id() was not marked as a
read-side critical section as reported by RCU lockdep:
=============================
WARNING: suspicious RCU usage
6.6.0-rc6 #7 Not tainted
-----------------------------
drivers/net/wireless/ath/ath11k/mac.c:638 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
no locks held by swapper/0/0.
...
Call trace:
...
lockdep_rcu_suspicious+0x16c/0x22c
ath11k_mac_get_ar_by_pdev_id+0x194/0x1b0 [ath11k]
ath11k_wmi_tlv_op_rx+0xa84/0x2c1c [ath11k]
ath11k_htc_rx_completion_handler+0x388/0x510 [ath11k]
Mark the code in question as an RCU read-side critical section to avoid
any potential use-after-free issues.
Fixes: a41d10348b01 ("ath11k: add thermal sensor device support")
Cc: stable@xxxxxxxxxxxxxxx # 5.7
Signed-off-by: Johan Hovold <johan+linaro@xxxxxxxxxx>
---
drivers/net/wireless/ath/ath11k/wmi.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/net/wireless/ath/ath11k/wmi.c b/drivers/net/wireless/ath/ath11k/wmi.c
index 23ad6825e5be..da1582b8dc30 100644
--- a/drivers/net/wireless/ath/ath11k/wmi.c
+++ b/drivers/net/wireless/ath/ath11k/wmi.c
@@ -8383,14 +8383,17 @@ ath11k_wmi_pdev_temperature_event(struct ath11k_base *ab,
ath11k_dbg(ab, ATH11K_DBG_WMI, "event pdev temperature ev temp %d pdev_id %d\n",
ev->temp, ev->pdev_id);
+ rcu_read_lock();
+
ar = ath11k_mac_get_ar_by_pdev_id(ab, ev->pdev_id);
if (!ar) {
ath11k_warn(ab, "invalid pdev id in pdev temperature ev %d", ev->pdev_id);
- kfree(tb);
- return;
+ goto exit;
}
ath11k_thermal_event_temperature(ar, ev->temp);
+exit:
+ rcu_read_unlock();
kfree(tb);
}
--
2.41.0
