From: Hans de Goede hdegoede@redhat.com
[ Upstream commit ef16799640865f937719f0771c93be5dca18adc6 ]
A received TKIP key may be up to 32 bytes because it may contain MIC rx/tx keys too. These are not used by iwl and copying these over overflows the iwl_keyinfo.key field.
Add a check to not copy more data to iwl_keyinfo.key then will fit.
This fixes backtraces like this one:
memcpy: detected field-spanning write (size 32) of single field "sta_cmd.key.key" at drivers/net/wireless/intel/iwlwifi/dvm/sta.c:1103 (size 16) WARNING: CPU: 1 PID: 946 at drivers/net/wireless/intel/iwlwifi/dvm/sta.c:1103 iwlagn_send_sta_key+0x375/0x390 [iwldvm] <snip> Hardware name: Dell Inc. Latitude E6430/0H3MT5, BIOS A21 05/08/2017 RIP: 0010:iwlagn_send_sta_key+0x375/0x390 [iwldvm] <snip> Call Trace: <TASK> iwl_set_dynamic_key+0x1f0/0x220 [iwldvm] iwlagn_mac_set_key+0x1e4/0x280 [iwldvm] drv_set_key+0xa4/0x1b0 [mac80211] ieee80211_key_enable_hw_accel+0xa8/0x2d0 [mac80211] ieee80211_key_replace+0x22d/0x8e0 [mac80211] <snip>
Link: https://www.alionet.org/index.php?topic=1469.0 Link: https://lore.kernel.org/linux-wireless/20230218191056.never.374-kees@kernel.... Link: https://lore.kernel.org/linux-wireless/68760035-7f75-1b23-e355-bfb758a87d83@... Cc: Kees Cook keescook@chromium.org Suggested-by: Johannes Berg johannes@sipsolutions.net Signed-off-by: Hans de Goede hdegoede@redhat.com Reviewed-by: Kees Cook keescook@chromium.org Signed-off-by: Johannes Berg johannes.berg@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/wireless/intel/iwlwifi/dvm/sta.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/net/wireless/intel/iwlwifi/dvm/sta.c b/drivers/net/wireless/intel/iwlwifi/dvm/sta.c index e622948661fa8..b307f0e527779 100644 --- a/drivers/net/wireless/intel/iwlwifi/dvm/sta.c +++ b/drivers/net/wireless/intel/iwlwifi/dvm/sta.c @@ -1086,6 +1086,7 @@ static int iwlagn_send_sta_key(struct iwl_priv *priv, { __le16 key_flags; struct iwl_addsta_cmd sta_cmd; + size_t to_copy; int i;
spin_lock_bh(&priv->sta_lock); @@ -1105,7 +1106,9 @@ static int iwlagn_send_sta_key(struct iwl_priv *priv, sta_cmd.key.tkip_rx_tsc_byte2 = tkip_iv32; for (i = 0; i < 5; i++) sta_cmd.key.tkip_rx_ttak[i] = cpu_to_le16(tkip_p1k[i]); - memcpy(sta_cmd.key.key, keyconf->key, keyconf->keylen); + /* keyconf may contain MIC rx/tx keys which iwl does not use */ + to_copy = min_t(size_t, sizeof(sta_cmd.key.key), keyconf->keylen); + memcpy(sta_cmd.key.key, keyconf->key, to_copy); break; case WLAN_CIPHER_SUITE_WEP104: key_flags |= STA_KEY_FLG_KEY_SIZE_MSK;