From 82a980f82a511ce74ab57eb9f692d02225eb32f4 Mon Sep 17 00:00:00 2001 From: Shayne Chen Date: Tue, 20 Jul 2021 10:48:32 +0800 Subject: [PATCH] mt76: mt7915: fix potential overflow of eeprom page index If total eeprom size is divisible by per-page size, the i in for loop will exceed max page index, which happens in our newer chipset. Fixes: 26f18380e6ca ("mt76: mt7915: add support for flash mode") Signed-off-by: Bo Jiao Signed-off-by: Shayne Chen Signed-off-by: Felix Fietkau --- drivers/net/wireless/mediatek/mt76/mt7915/mcu.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/mcu.c b/drivers/net/wireless/mediatek/mt76/mt7915/mcu.c index 813092ca2a81..57c6dbcb1af3 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7915/mcu.c +++ b/drivers/net/wireless/mediatek/mt76/mt7915/mcu.c @@ -3244,20 +3244,20 @@ int mt7915_mcu_set_chan_info(struct mt7915_phy *phy, int cmd) static int mt7915_mcu_set_eeprom_flash(struct mt7915_dev *dev) { -#define TOTAL_PAGE_MASK GENMASK(7, 5) +#define MAX_PAGE_IDX_MASK GENMASK(7, 5) #define PAGE_IDX_MASK GENMASK(4, 2) #define PER_PAGE_SIZE 0x400 struct mt7915_mcu_eeprom req = { .buffer_mode = EE_MODE_BUFFER }; - u8 total = MT7915_EEPROM_SIZE / PER_PAGE_SIZE; + u8 total = DIV_ROUND_UP(MT7915_EEPROM_SIZE, PER_PAGE_SIZE); u8 *eep = (u8 *)dev->mt76.eeprom.data; int eep_len; int i; - for (i = 0; i <= total; i++, eep += eep_len) { + for (i = 0; i < total; i++, eep += eep_len) { struct sk_buff *skb; int ret; - if (i == total) + if (i == total - 1 && !!(MT7915_EEPROM_SIZE % PER_PAGE_SIZE)) eep_len = MT7915_EEPROM_SIZE % PER_PAGE_SIZE; else eep_len = PER_PAGE_SIZE; @@ -3267,7 +3267,7 @@ static int mt7915_mcu_set_eeprom_flash(struct mt7915_dev *dev) if (!skb) return -ENOMEM; - req.format = FIELD_PREP(TOTAL_PAGE_MASK, total) | + req.format = FIELD_PREP(MAX_PAGE_IDX_MASK, total - 1) | FIELD_PREP(PAGE_IDX_MASK, i) | EE_FORMAT_WHOLE; req.len = cpu_to_le16(eep_len); -- 2.11.0