2021-06-17 04:15:06

by Kees Cook

[permalink] [raw]
Subject: [PATCH v2] mwl8k: Avoid memcpy() over-reading of mcs.rx_mask

In preparation for FORTIFY_SOURCE performing compile-time and run-time
field bounds checking for memcpy(), memmove(), and memset(), avoid
intentionally reading across neighboring array fields. Use the
sub-structure address directly.

Signed-off-by: Kees Cook <[email protected]>
---
v2: fix Subject for actual issue
v1: https://lore.kernel.org/lkml/[email protected]
---
drivers/net/wireless/marvell/mwl8k.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/marvell/mwl8k.c b/drivers/net/wireless/marvell/mwl8k.c
index 84b32a5f01ee..3bf6571f4149 100644
--- a/drivers/net/wireless/marvell/mwl8k.c
+++ b/drivers/net/wireless/marvell/mwl8k.c
@@ -4552,7 +4552,7 @@ static int mwl8k_cmd_update_stadb_add(struct ieee80211_hw *hw,
else
rates = sta->supp_rates[NL80211_BAND_5GHZ] << 5;
legacy_rate_mask_to_array(p->legacy_rates, rates);
- memcpy(p->ht_rates, sta->ht_cap.mcs.rx_mask, 16);
+ memcpy(p->ht_rates, &sta->ht_cap.mcs, 16);
p->interop = 1;
p->amsdu_enabled = 0;

@@ -5034,7 +5034,7 @@ mwl8k_bss_info_changed_sta(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
ap_legacy_rates =
ap->supp_rates[NL80211_BAND_5GHZ] << 5;
}
- memcpy(ap_mcs_rates, ap->ht_cap.mcs.rx_mask, 16);
+ memcpy(ap_mcs_rates, &ap->ht_cap.mcs, 16);

rcu_read_unlock();

--
2.25.1