[PATCH 5.19 226/717] wifi: rtl8xxxu: tighten bounds checking in rtl8xxxu_read_efuse()

Greg Kroah-Hartman
2022-10-22T07:55:19Z

From: Dan Carpenter <dan.carpenter@oracle.com>

[ Upstream commit 620d5eaeb9059636864bda83ca1c68c20ede34a5 ]

There some bounds checking to ensure that "map_addr" is not out of
bounds before the start of the loop. But the checking needs to be
done as we iterate through the loop because "map_addr" gets larger as
we iterate.

Fixes: 26f1fad29ad9 ("New driver: rtl8xxxu (mac80211)")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Jes Sorensen <Jes.Sorensen@gmail.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/Yv8eGLdBslLAk3Ct@kili
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
.../net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
index 8b2ca9e8eac6..7f09359a238f 100644
--- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
+++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
@@ -1878,13 +1878,6 @@ static int rtl8xxxu_read_efuse(struct rtl8xxxu_priv *priv)

/* We have 8 bits to indicate validity */
map_addr = offset * 8;
- if (map_addr >= EFUSE_MAP_LEN) {
- dev_warn(dev, "%s: Illegal map_addr (%04x), "
- "efuse corrupt!\n",
- __func__, map_addr);
- ret = -EINVAL;
- goto exit;
- }
for (i = 0; i < EFUSE_MAX_WORD_UNIT; i++) {
/* Check word enable condition in the section */
if (word_mask & BIT(i)) {
@@ -1895,6 +1888,13 @@ static int rtl8xxxu_read_efuse(struct rtl8xxxu_priv *priv)
ret = rtl8xxxu_read_efuse8(priv, efuse_addr++, &val8);
if (ret)
goto exit;
+ if (map_addr >= EFUSE_MAP_LEN - 1) {
+ dev_warn(dev, "%s: Illegal map_addr (%04x), "
+ "efuse corrupt!\n",
+ __func__, map_addr);
+ ret = -EINVAL;
+ goto exit;
+ }
priv->efuse_wifi.raw[map_addr++] = val8;

ret = rtl8xxxu_read_efuse8(priv, efuse_addr++, &val8);
--
2.35.1