[PATCH] mt76: fix possible OOB issue in mt76_calculate_default_rate
From: Lorenzo Bianconi <lorenzo@kernel.org>
Date: 2021-11-18 10:42:15
Subsystem:
mediatek mt76 wireless lan driver, the rest · Maintainers:
Felix Fietkau, Lorenzo Bianconi, Ryder Lee, Linus Torvalds
Cap max offset value to ARRAY_SIZE(mt76_rates) - 1 in
mt76_calculate_default_rate routine in order to avoid possible Out Of
Bound accesses.
Fixes: 33920b2bf0483 ("mt76: add support for setting mcast rate")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
---
drivers/net/wireless/mediatek/mt76/mac80211.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/drivers/net/wireless/mediatek/mt76/mac80211.c b/drivers/net/wireless/mediatek/mt76/mac80211.c
index 62807dc311c1..b0869ff86c49 100644
--- a/drivers/net/wireless/mediatek/mt76/mac80211.c
+++ b/drivers/net/wireless/mediatek/mt76/mac80211.c@@ -1494,7 +1494,6 @@ EXPORT_SYMBOL_GPL(mt76_init_queue); u16 mt76_calculate_default_rate(struct mt76_phy *phy, int rateidx) { int offset = 0; - struct ieee80211_rate *rate; if (phy->chandef.chan->band != NL80211_BAND_2GHZ) offset = 4;
@@ -1503,9 +1502,11 @@ u16 mt76_calculate_default_rate(struct mt76_phy *phy, int rateidx) if (rateidx < 0) rateidx = 0; - rate = &mt76_rates[offset + rateidx]; + rateidx += offset; + if (rateidx >= ARRAY_SIZE(mt76_rates)) + rateidx = offset; - return rate->hw_value; + return mt76_rates[rateidx].hw_value; } EXPORT_SYMBOL_GPL(mt76_calculate_default_rate);
--
2.31.1