From 2aca4f3734bd717e04943ddf340d49ab62299a00 Mon Sep 17 00:00:00 2001
From: Wright Feng <wright.feng@cypress.com>
Date: Wed, 28 Sep 2022 22:10:00 -0500
Subject: [PATCH] brcmfmac: return error when getting invalid max_flowrings from dongle
Git-commit: 2aca4f3734bd717e04943ddf340d49ab62299a00
Patch-mainline: v6.2-rc1
References: git-fixes

When firmware hit trap at initialization, host will read abnormal
max_flowrings number from dongle, and it will cause kernel panic when
doing iowrite to initialize dongle ring.
To detect this error at early stage, we directly return error when getting
invalid max_flowrings(>256).

Signed-off-by: Wright Feng <wright.feng@cypress.com>
Signed-off-by: Chi-hsien Lin <chi-hsien.lin@cypress.com>
Signed-off-by: Ian Lin <ian.lin@infineon.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20220929031001.9962-3-ian.lin@infineon.com
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/net/wireless/broadcom/brcm80211/brcmfmac/pcie.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/pcie.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/pcie.c
index 2b7ebbd7b5b4..1becd50038ab 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/pcie.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/pcie.c
@@ -1228,6 +1228,10 @@ static int brcmf_pcie_init_ringbuffers(struct brcmf_pciedev_info *devinfo)
 				BRCMF_NROF_H2D_COMMON_MSGRINGS;
 		max_completionrings = BRCMF_NROF_D2H_COMMON_MSGRINGS;
 	}
+	if (max_flowrings > 256) {
+		brcmf_err(bus, "invalid max_flowrings(%d)\n", max_flowrings);
+		return -EIO;
+	}
 
 	if (devinfo->dma_idx_sz != 0) {
 		bufsz = (max_submissionrings + max_completionrings) *
-- 
2.35.3