[SRU][J][PATCH 1/1] wifi: ath11k: add srng->lock for ath11k_hal_srng_* in monitor mode

[Cengiz Can]

From: Kang Yang <quic_kangyang at quicinc.com>

ath11k_hal_srng_* should be used with srng->lock to protect srng data.

For ath11k_dp_rx_mon_dest_process() and ath11k_dp_full_mon_process_rx(),
they use ath11k_hal_srng_* for many times but never call srng->lock.

So when running (full) monitor mode, warning will occur:
RIP: 0010:ath11k_hal_srng_dst_peek+0x18/0x30 [ath11k]
Call Trace:
 ? ath11k_hal_srng_dst_peek+0x18/0x30 [ath11k]
 ath11k_dp_rx_process_mon_status+0xc45/0x1190 [ath11k]
 ? idr_alloc_u32+0x97/0xd0
 ath11k_dp_rx_process_mon_rings+0x32a/0x550 [ath11k]
 ath11k_dp_service_srng+0x289/0x5a0 [ath11k]
 ath11k_pcic_ext_grp_napi_poll+0x30/0xd0 [ath11k]
 __napi_poll+0x30/0x1f0
 net_rx_action+0x198/0x320
 __do_softirq+0xdd/0x319

So add srng->lock for them to avoid such warnings.

Inorder to fetch the srng->lock, should change srng's definition from
'void' to 'struct hal_srng'. And initialize them elsewhere to prevent
one line of code from being too long. This is consistent with other ring
process functions, such as ath11k_dp_process_rx().

Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.30
Tested-on: QCN9074 hw1.0 PCI WLAN.HK.2.7.0.1-01744-QCAHKSWPL_SILICONZ-1

Fixes: d5c65159f289 ("ath11k: driver for Qualcomm IEEE 802.11ax devices")
Signed-off-by: Kang Yang <quic_kangyang at quicinc.com>
Acked-by: Jeff Johnson <quic_jjohnson at quicinc.com>
Link: https://patch.msgid.link/20241219110531.2096-3-quic_kangyang@quicinc.com
Signed-off-by: Jeff Johnson <jeff.johnson at oss.qualcomm.com>
(backported from commit 63b7af49496d0e32f7a748b6af3361ec138b1bd3)
[bot_kybele: Applied only the ath11k_dp_rx_mon_dest_process locking hunk (srng
 type + srng->lock); dropped the ath11k_dp_full_mon_process_rx hunk because full
 monitor mode (that function and its ath11k_mon_data members) does not exist in
 this tree, so git 3-way had injected the whole full-mon function block, which
 was removed.]
CVE-2024-58096
Assisted-by: kybele:claude-opus-4.8
Signed-off-by: Cengiz Can <cengiz.can at canonical.com>
---
 drivers/net/wireless/ath/ath11k/dp_rx.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/ath/ath11k/dp_rx.c b/drivers/net/wireless/ath/ath11k/dp_rx.c
index c075ab493456..c053bbd9c103 100644
--- a/drivers/net/wireless/ath/ath11k/dp_rx.c
+++ b/drivers/net/wireless/ath/ath11k/dp_rx.c
@@ -4915,7 +4915,7 @@ static void ath11k_dp_rx_mon_dest_process(struct ath11k *ar, int mac_id,
 	struct ath11k_pdev_dp *dp = &ar->dp;
 	struct ath11k_mon_data *pmon = (struct ath11k_mon_data *)&dp->mon_data;
 	void *ring_entry;
-	void *mon_dst_srng;
+	struct hal_srng *mon_dst_srng;
 	u32 ppdu_id;
 	u32 rx_bufs_used;
 	u32 ring_id;
@@ -4938,6 +4938,7 @@ static void ath11k_dp_rx_mon_dest_process(struct ath11k *ar, int mac_id,
 
 	spin_lock_bh(&pmon->mon_lock);
 
+	spin_lock_bh(&mon_dst_srng->lock);
 	ath11k_hal_srng_access_begin(ar->ab, mon_dst_srng);
 
 	ppdu_id = pmon->mon_ppdu_info.ppdu_id;
@@ -4972,6 +4973,7 @@ static void ath11k_dp_rx_mon_dest_process(struct ath11k *ar, int mac_id,
 								mon_dst_srng);
 	}
 	ath11k_hal_srng_access_end(ar->ab, mon_dst_srng);
+	spin_unlock_bh(&mon_dst_srng->lock);
 
 	spin_unlock_bh(&pmon->mon_lock);
 
-- 
2.53.0