Search Linux Wireless

Re: [PATCH 1/2] wifi: ath11k: fix temperature event locking

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 10/19/2023 3:42 AM, Johan Hovold wrote:
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:

How do I enable this? Just enable CONFIG_PROVE_RCU?
Of course I'd also need to exercise the code path...


	=============================
	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 | 4 ++++
  1 file changed, 4 insertions(+)

diff --git a/drivers/net/wireless/ath/ath11k/wmi.c b/drivers/net/wireless/ath/ath11k/wmi.c
index 23ad6825e5be..980ff588325d 100644
--- a/drivers/net/wireless/ath/ath11k/wmi.c
+++ b/drivers/net/wireless/ath/ath11k/wmi.c
@@ -8383,6 +8383,8 @@ 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);

aren't you missing an unlock() in this error path?

perhaps have a goto cleanup that does both the unlock() and the kfree()?

@@ -8392,6 +8394,8 @@ ath11k_wmi_pdev_temperature_event(struct ath11k_base *ab,
ath11k_thermal_event_temperature(ar, ev->temp); + rcu_read_unlock();
+
  	kfree(tb);
  }




[Index of Archives]     [Linux Host AP]     [ATH6KL]     [Linux Wireless Personal Area Network]     [Linux Bluetooth]     [Wireless Regulations]     [Linux Netdev]     [Kernel Newbies]     [Linux Kernel]     [IDE]     [Git]     [Netfilter]     [Bugtraq]     [Yosemite Hiking]     [MIPS Linux]     [ARM Linux]     [Linux RAID]

  Powered by Linux