6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Johan Hovold johan+linaro@kernel.org
commit 1a5352a81b4720ba43d9c899974e3bddf7ce0ce8 upstream.
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.
Tested-on: WCN6855 hw2.1 PCI WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.23
Fixes: a41d10348b01 ("ath11k: add thermal sensor device support") Cc: stable@vger.kernel.org # 5.7 Signed-off-by: Johan Hovold johan+linaro@kernel.org Acked-by: Jeff Johnson quic_jjohnson@quicinc.com Signed-off-by: Kalle Valo quic_kvalo@quicinc.com Link: https://lore.kernel.org/r/20231019153115.26401-2-johan+linaro@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/wireless/ath/ath11k/wmi.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
--- a/drivers/net/wireless/ath/ath11k/wmi.c +++ b/drivers/net/wireless/ath/ath11k/wmi.c @@ -8383,15 +8383,19 @@ ath11k_wmi_pdev_temperature_event(struct 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); }