wifi: wilc1000: validate length of IEEE80211_P2P_ATTR_CHANNEL_LIST attribute
Validate that the IEEE80211_P2P_ATTR_CHANNEL_LIST attribute contains
enough space for a 'struct wilc_attr_oper_ch'. If the attribute is too
small then it can trigger an out-of-bounds write later in the function.
'struct wilc_attr_oper_ch' is variable sized so also check 'attr_len'
does not extend beyond the end of 'buf'.
Signed-off-by: Phil Turnbull <philipturnbull@github.com>
Tested-by: Ajay Kathat <ajay.kathat@microchip.com>
Acked-by: Ajay Kathat <ajay.kathat@microchip.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20221123153543.8568-4-philipturnbull@github.com
diff --git a/drivers/net/wireless/microchip/wilc1000/cfg80211.c b/drivers/net/wireless/microchip/wilc1000/cfg80211.c
index aedf0e8..c4d5a27 100644
--- a/drivers/net/wireless/microchip/wilc1000/cfg80211.c
+++ b/drivers/net/wireless/microchip/wilc1000/cfg80211.c
@@ -967,7 +967,8 @@
if (index + sizeof(*e) + attr_size > len)
return;
- if (e->attr_type == IEEE80211_P2P_ATTR_CHANNEL_LIST)
+ if (e->attr_type == IEEE80211_P2P_ATTR_CHANNEL_LIST &&
+ attr_size >= (sizeof(struct wilc_attr_ch_list) - sizeof(*e)))
ch_list_idx = index;
else if (e->attr_type == IEEE80211_P2P_ATTR_OPER_CHANNEL &&
attr_size == (sizeof(struct wilc_attr_oper_ch) - sizeof(*e)))