[PATCH 5.1 123/405] rsi: Fix NULL pointer dereference in kmalloc

From: Greg Kroah-Hartman
Date: Thu May 30 2019 - 00:51:48 EST


[ Upstream commit d5414c2355b20ea8201156d2e874265f1cb0d775 ]

kmalloc can fail in rsi_register_rates_channels but memcpy still attempts
to write to channels. The patch replaces these calls with kmemdup and
passes the error upstream.

Signed-off-by: Aditya Pakki <pakki001@xxxxxxx>
Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/wireless/rsi/rsi_91x_mac80211.c | 30 ++++++++++++---------
1 file changed, 18 insertions(+), 12 deletions(-)

diff --git a/drivers/net/wireless/rsi/rsi_91x_mac80211.c b/drivers/net/wireless/rsi/rsi_91x_mac80211.c
index 831046e760f8a..49df3bb08d41f 100644
--- a/drivers/net/wireless/rsi/rsi_91x_mac80211.c
+++ b/drivers/net/wireless/rsi/rsi_91x_mac80211.c
@@ -188,27 +188,27 @@ bool rsi_is_cipher_wep(struct rsi_common *common)
* @adapter: Pointer to the adapter structure.
* @band: Operating band to be set.
*
- * Return: None.
+ * Return: int - 0 on success, negative error on failure.
*/
-static void rsi_register_rates_channels(struct rsi_hw *adapter, int band)
+static int rsi_register_rates_channels(struct rsi_hw *adapter, int band)
{
struct ieee80211_supported_band *sbands = &adapter->sbands[band];
void *channels = NULL;

if (band == NL80211_BAND_2GHZ) {
- channels = kmalloc(sizeof(rsi_2ghz_channels), GFP_KERNEL);
- memcpy(channels,
- rsi_2ghz_channels,
- sizeof(rsi_2ghz_channels));
+ channels = kmemdup(rsi_2ghz_channels, sizeof(rsi_2ghz_channels),
+ GFP_KERNEL);
+ if (!channels)
+ return -ENOMEM;
sbands->band = NL80211_BAND_2GHZ;
sbands->n_channels = ARRAY_SIZE(rsi_2ghz_channels);
sbands->bitrates = rsi_rates;
sbands->n_bitrates = ARRAY_SIZE(rsi_rates);
} else {
- channels = kmalloc(sizeof(rsi_5ghz_channels), GFP_KERNEL);
- memcpy(channels,
- rsi_5ghz_channels,
- sizeof(rsi_5ghz_channels));
+ channels = kmemdup(rsi_5ghz_channels, sizeof(rsi_5ghz_channels),
+ GFP_KERNEL);
+ if (!channels)
+ return -ENOMEM;
sbands->band = NL80211_BAND_5GHZ;
sbands->n_channels = ARRAY_SIZE(rsi_5ghz_channels);
sbands->bitrates = &rsi_rates[4];
@@ -227,6 +227,7 @@ static void rsi_register_rates_channels(struct rsi_hw *adapter, int band)
sbands->ht_cap.mcs.rx_mask[0] = 0xff;
sbands->ht_cap.mcs.tx_params = IEEE80211_HT_MCS_TX_DEFINED;
/* sbands->ht_cap.mcs.rx_highest = 0x82; */
+ return 0;
}

static int rsi_mac80211_hw_scan_start(struct ieee80211_hw *hw,
@@ -2064,11 +2065,16 @@ int rsi_mac80211_attach(struct rsi_common *common)
wiphy->available_antennas_rx = 1;
wiphy->available_antennas_tx = 1;

- rsi_register_rates_channels(adapter, NL80211_BAND_2GHZ);
+ status = rsi_register_rates_channels(adapter, NL80211_BAND_2GHZ);
+ if (status)
+ return status;
wiphy->bands[NL80211_BAND_2GHZ] =
&adapter->sbands[NL80211_BAND_2GHZ];
if (common->num_supp_bands > 1) {
- rsi_register_rates_channels(adapter, NL80211_BAND_5GHZ);
+ status = rsi_register_rates_channels(adapter,
+ NL80211_BAND_5GHZ);
+ if (status)
+ return status;
wiphy->bands[NL80211_BAND_5GHZ] =
&adapter->sbands[NL80211_BAND_5GHZ];
}
--
2.20.1