[PATCH 5.10 060/152] ath11k: fix crash caused by NULL rx_channel

From: Greg Kroah-Hartman
Date: Mon Jan 18 2021 - 09:39:15 EST


From: Carl Huang <cjhuang@xxxxxxxxxxxxxx>

[ Upstream commit 3597010630d0aa96f5778901e691c6068bb86318 ]

During connect and disconnect stress test, crashed happened
because ar->rx_channel is NULL. Fix it by checking whether
ar->rx_channel is NULL.

Crash stack is as below:
RIP: 0010:ath11k_dp_rx_h_ppdu+0x110/0x230 [ath11k]
[ 5028.808963] ath11k_dp_rx_wbm_err+0x14a/0x360 [ath11k]
[ 5028.808970] ath11k_dp_rx_process_wbm_err+0x41c/0x520 [ath11k]
[ 5028.808978] ath11k_dp_service_srng+0x25e/0x2d0 [ath11k]
[ 5028.808982] ath11k_pci_ext_grp_napi_poll+0x23/0x80 [ath11k_pci]
[ 5028.808986] net_rx_action+0x27e/0x400
[ 5028.808990] __do_softirq+0xfd/0x2bb
[ 5028.808993] irq_exit+0xa6/0xb0
[ 5028.808995] do_IRQ+0x56/0xe0
[ 5028.808997] common_interrupt+0xf/0xf

Tested-on: QCA6390 hw2.0 PCI WLAN.HST.1.0.1-01740-QCAHSTSWPLZ_V2_TO_X86-1

Signed-off-by: Carl Huang <cjhuang@xxxxxxxxxxxxxx>
Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20201211055613.9310-1-cjhuang@xxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/wireless/ath/ath11k/dp_rx.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/ath/ath11k/dp_rx.c b/drivers/net/wireless/ath/ath11k/dp_rx.c
index 01625327eef7c..3638501a09593 100644
--- a/drivers/net/wireless/ath/ath11k/dp_rx.c
+++ b/drivers/net/wireless/ath/ath11k/dp_rx.c
@@ -2272,6 +2272,7 @@ static void ath11k_dp_rx_h_ppdu(struct ath11k *ar, struct hal_rx_desc *rx_desc,
{
u8 channel_num;
u32 center_freq;
+ struct ieee80211_channel *channel;

rx_status->freq = 0;
rx_status->rate_idx = 0;
@@ -2292,9 +2293,12 @@ static void ath11k_dp_rx_h_ppdu(struct ath11k *ar, struct hal_rx_desc *rx_desc,
rx_status->band = NL80211_BAND_5GHZ;
} else {
spin_lock_bh(&ar->data_lock);
- rx_status->band = ar->rx_channel->band;
- channel_num =
- ieee80211_frequency_to_channel(ar->rx_channel->center_freq);
+ channel = ar->rx_channel;
+ if (channel) {
+ rx_status->band = channel->band;
+ channel_num =
+ ieee80211_frequency_to_channel(channel->center_freq);
+ }
spin_unlock_bh(&ar->data_lock);
ath11k_dbg_dump(ar->ab, ATH11K_DBG_DATA, NULL, "rx_desc: ",
rx_desc, sizeof(struct hal_rx_desc));
--
2.27.0