From b43f4a169f220e459edf3ea8f8cd3ec4ae7fa82d Mon Sep 17 00:00:00 2001
From: Larry Finger <Larry.Finger@lwfinger.net>
Date: Sun, 20 Oct 2019 19:56:58 -0500
Subject: [PATCH] rtlwifi: rtl_pci: Fix problem of too small skb->len
Git-commit: b43f4a169f220e459edf3ea8f8cd3ec4ae7fa82d
Patch-mainline: v5.4-rc6
References: git-fixes bnc#1151927 5.3.9
In commit 8020919a9b99 ("mac80211: Properly handle SKB with radiotap
only"), buffers whose length is too short cause a WARN_ON(1) to be
executed. This change exposed a fault in rtlwifi drivers, which is fixed
by regarding packets with skb->len <= FCS_LEN as though they are in error
and dropping them. The test is now annotated as likely.
Cc: Stable <stable@vger.kernel.org> # v5.0+
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/net/wireless/realtek/rtlwifi/pci.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/net/wireless/realtek/rtlwifi/pci.c b/drivers/net/wireless/realtek/rtlwifi/pci.c
index 6087ec7a90a6..f88d26535978 100644
--- a/drivers/net/wireless/realtek/rtlwifi/pci.c
+++ b/drivers/net/wireless/realtek/rtlwifi/pci.c
@@ -822,7 +822,7 @@ static void _rtl_pci_rx_interrupt(struct ieee80211_hw *hw)
hdr = rtl_get_hdr(skb);
fc = rtl_get_fc(skb);
- if (!stats.crc && !stats.hwerror) {
+ if (!stats.crc && !stats.hwerror && (skb->len > FCS_LEN)) {
memcpy(IEEE80211_SKB_RXCB(skb), &rx_status,
sizeof(rx_status));
@@ -859,6 +859,7 @@ static void _rtl_pci_rx_interrupt(struct ieee80211_hw *hw)
_rtl_pci_rx_to_mac80211(hw, skb, rx_status);
}
} else {
+ /* drop packets with errors or those too short */
dev_kfree_skb_any(skb);
}
new_trx_end:
--
2.16.4