[PATCH] drivers:wireless: Fix a dereference before null check issue

From: Paolo Perego
Date: Thu Nov 21 2024 - 12:05:14 EST


This patch fixes a dereference before null check issue discovered by
Coverity (CID 1601547)

In iwl_mvm_parse_wowlan_info_notif() routine data is checked against
NULL value at line 2501 but it has been dereferenced three lines before
when calculating sizeof() in an assignment.

Signed-off-by: Paolo Perego <pperego@xxxxxxx>
---
drivers/net/wireless/intel/iwlwifi/mvm/d3.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/d3.c b/drivers/net/wireless/intel/iwlwifi/mvm/d3.c
index f85c01e04ebf..f733c16ffd8e 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/d3.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/d3.c
@@ -2495,8 +2495,7 @@ static void iwl_mvm_parse_wowlan_info_notif(struct iwl_mvm *mvm,
struct iwl_wowlan_status_data *status,
u32 len)
{
- u32 expected_len = sizeof(*data) +
- data->num_mlo_link_keys * sizeof(status->mlo_keys[0]);
+ u32 expected_len = 0;

if (!data) {
IWL_ERR(mvm, "iwl_wowlan_info_notif data is NULL\n");
@@ -2504,6 +2503,8 @@ static void iwl_mvm_parse_wowlan_info_notif(struct iwl_mvm *mvm,
return;
}

+ expected_len = sizeof(*data) + data->num_mlo_link_keys * sizeof(status->mlo_keys[0]);
+
if (len < expected_len) {
IWL_ERR(mvm, "Invalid WoWLAN info notification!\n");
status = NULL;
--
2.47.0