Re: [PATCH v2 1/2] wifi: ath11k: fix temperature event locking

From: Jeff Johnson
Date: Thu Oct 19 2023 - 13:14:46 EST


On 10/19/2023 8:31 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:

=============================
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>
Acked-by: Jeff Johnson <quic_jjohnson@xxxxxxxxxxx>