[PATCH] wifi: rtw88: Add NULL check for chip->edcca_th

[Panagiotis Petrakopoulos <npetrakopoulos2003@gmail.com>]

It was recently reported that rtw_fw_adaptivity_result
in fw.c dereferences rtwdev->chip->edcca_th without
a null check. The issue appears to be that devices
with the 8821CE chip don't define edcca_th in their
chip info. As a result, when rtw_fw_adaptivity_result
tries to dereference it, the kernel triggers an oops.

Add a NULL check for edcca_th before dereferencing
it in rtw_fw_adaptivity_result() in fw.c and
rtw_phy_set_edcca_th() in phy.c.

Tested on a 8822CE chip which defines edcca_th, so
this issue is not present on it, but it still uses
this driver and I can verify there are no regressions.

Reported-by: Oleksandr Havrylov <goainwo@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=221286
Link: https://lore.kernel.org/linux-wireless/CALdGYqQriS7mP0vj_rm_xvisfzFVh0hbpy+---48r6bodZO7tg@mail.gmail.com/
Signed-off-by: Panagiotis Petrakopoulos <npetrakopoulos2003@gmail.com>
---
 drivers/net/wireless/realtek/rtw88/fw.c  | 3 +++
 drivers/net/wireless/realtek/rtw88/phy.c | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/drivers/net/wireless/realtek/rtw88/fw.c b/drivers/net/wireless/realtek/rtw88/fw.c
index 48207052e3f8..c4819ef6d54d 100644
--- a/drivers/net/wireless/realtek/rtw88/fw.c
+++ b/drivers/net/wireless/realtek/rtw88/fw.c
@@ -284,6 +284,9 @@ static void rtw_fw_adaptivity_result(struct rtw_dev *rtwdev, u8 *payload,
 		result->density, result->igi, result->l2h_th_init, result->l2h,
 		result->h2l, result->option);
 
+	if (!edcca_th)
+		return;
+
 	rtw_dbg(rtwdev, RTW_DBG_ADAPTIVITY, "Reg Setting: L2H %x H2L %x\n",
 		rtw_read32_mask(rtwdev, edcca_th[EDCCA_TH_L2H_IDX].hw_reg.addr,
 				edcca_th[EDCCA_TH_L2H_IDX].hw_reg.mask),
diff --git a/drivers/net/wireless/realtek/rtw88/phy.c b/drivers/net/wireless/realtek/rtw88/phy.c
index e2ac5c6fd500..c10eb28e54ad 100644
--- a/drivers/net/wireless/realtek/rtw88/phy.c
+++ b/drivers/net/wireless/realtek/rtw88/phy.c
@@ -161,6 +161,9 @@ void rtw_phy_set_edcca_th(struct rtw_dev *rtwdev, u8 l2h, u8 h2l)
 {
 	const struct rtw_hw_reg_offset *edcca_th = rtwdev->chip->edcca_th;
 
+	if (!edcca_th)
+		return;
+
 	rtw_write32_mask(rtwdev,
 			 edcca_th[EDCCA_TH_L2H_IDX].hw_reg.addr,
 			 edcca_th[EDCCA_TH_L2H_IDX].hw_reg.mask,
-- 
2.53.0