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From:   Ian Lin <ian.lin@infineon.com>
To:     <linux-wireless@vger.kernel.org>
CC:     <brcm80211-dev-list@broadcom.com>,
        <brcm80211-dev-list@cypress.com>, <franky.lin@broadcom.com>,
        <hante.meuleman@broadcom.com>, <kvalo@kernel.org>,
        <Double.Lo@infineon.com>, <ian.lin@infineon.com>
Subject: [PATCH 2/3] brcmfmac: return error when getting invalid max_flowrings from dongle
Date:   Wed, 28 Sep 2022 22:10:00 -0500
Message-ID: <20220929031001.9962-3-ian.lin@infineon.com>
In-Reply-To: <20220929031001.9962-1-ian.lin@infineon.com>
References: <20220929031001.9962-1-ian.lin@infineon.com>
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From: Wright Feng <wright.feng@cypress.com>

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>
---
 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) *
-- 
2.25.0