From 72c08d9f4c72787dde541ae5ed278e46771c9f2a Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Fri, 23 Sep 2022 15:08:53 -0700 Subject: wifi: iwlwifi: Track scan_cmd allocation size explicitly In preparation for reducing the use of ksize(), explicitly track the size of scan_cmd allocations. This also allows for noticing if the scan size changes unexpectedly. Note that using ksize() was already incorrect here, in the sense that ksize() would not match the actual allocation size, which would trigger future run-time allocation bounds checking. (In other words, memset() may know how large scan_cmd was allocated for, but ksize() will return the upper bounds of the actually allocated memory, causing a run-time warning about an overflow.) Cc: Gregory Greenman Cc: Kalle Valo Cc: "David S. Miller" Cc: Eric Dumazet Cc: Jakub Kicinski Cc: Paolo Abeni Cc: Luca Coelho Cc: Johannes Berg Cc: Emmanuel Grumbach Cc: Miri Korenblit Cc: Ilan Peer Cc: linux-wireless@vger.kernel.org Cc: netdev@vger.kernel.org Signed-off-by: Kees Cook Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/20220923220853.3302056-1-keescook@chromium.org --- drivers/net/wireless/intel/iwlwifi/dvm/dev.h | 1 + drivers/net/wireless/intel/iwlwifi/dvm/scan.c | 10 ++++++++-- 2 files changed, 9 insertions(+), 2 deletions(-) (limited to 'drivers/net/wireless/intel/iwlwifi/dvm') diff --git a/drivers/net/wireless/intel/iwlwifi/dvm/dev.h b/drivers/net/wireless/intel/iwlwifi/dvm/dev.h index bbd574091201..1a9eadace188 100644 --- a/drivers/net/wireless/intel/iwlwifi/dvm/dev.h +++ b/drivers/net/wireless/intel/iwlwifi/dvm/dev.h @@ -696,6 +696,7 @@ struct iwl_priv { /* Scan related variables */ unsigned long scan_start; unsigned long scan_start_tsf; + size_t scan_cmd_size; void *scan_cmd; enum nl80211_band scan_band; struct cfg80211_scan_request *scan_request; diff --git a/drivers/net/wireless/intel/iwlwifi/dvm/scan.c b/drivers/net/wireless/intel/iwlwifi/dvm/scan.c index 2d38227dfdd2..a7e85c5c8c72 100644 --- a/drivers/net/wireless/intel/iwlwifi/dvm/scan.c +++ b/drivers/net/wireless/intel/iwlwifi/dvm/scan.c @@ -626,7 +626,7 @@ static int iwlagn_request_scan(struct iwl_priv *priv, struct ieee80211_vif *vif) u8 active_chains; u8 scan_tx_antennas = priv->nvm_data->valid_tx_ant; int ret; - int scan_cmd_size = sizeof(struct iwl_scan_cmd) + + size_t scan_cmd_size = sizeof(struct iwl_scan_cmd) + MAX_SCAN_CHANNEL * sizeof(struct iwl_scan_channel) + priv->fw->ucode_capa.max_probe_length; const u8 *ssid = NULL; @@ -649,9 +649,15 @@ static int iwlagn_request_scan(struct iwl_priv *priv, struct ieee80211_vif *vif) "fail to allocate memory for scan\n"); return -ENOMEM; } + priv->scan_cmd_size = scan_cmd_size; + } + if (priv->scan_cmd_size < scan_cmd_size) { + IWL_DEBUG_SCAN(priv, + "memory needed for scan grew unexpectedly\n"); + return -ENOMEM; } scan = priv->scan_cmd; - memset(scan, 0, scan_cmd_size); + memset(scan, 0, priv->scan_cmd_size); scan->quiet_plcp_th = IWL_PLCP_QUIET_THRESH; scan->quiet_time = IWL_ACTIVE_QUIET_TIME; -- cgit