From ef16799640865f937719f0771c93be5dca18adc6 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Tue, 18 Apr 2023 15:25:46 +0200 Subject: [PATCH] wifi: iwlwifi: dvm: Fix memcpy: detected field-spanning write backtrace 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] Hardware name: Dell Inc. Latitude E6430/0H3MT5, BIOS A21 05/08/2017 RIP: 0010:iwlagn_send_sta_key+0x375/0x390 [iwldvm] Call Trace: 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] Link: https://www.alionet.org/index.php?topic=1469.0 Link: https://lore.kernel.org/linux-wireless/20230218191056.never.374-kees@kernel.org/ Link: https://lore.kernel.org/linux-wireless/68760035-7f75-1b23-e355-bfb758a87d83@redhat.com/ Cc: Kees Cook Suggested-by: Johannes Berg Signed-off-by: Hans de Goede Reviewed-by: Kees Cook Signed-off-by: Johannes Berg --- 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 cef43cf..8b01ab9 100644 --- a/drivers/net/wireless/intel/iwlwifi/dvm/sta.c +++ b/drivers/net/wireless/intel/iwlwifi/dvm/sta.c @@ -1081,6 +1081,7 @@ 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); @@ -1100,7 +1101,9 @@ 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; -- 2.7.4