[PATCH 5.14 480/849] iwlwifi: pnvm: read EFI data only if long enough

Greg Kroah-Hartman
2021-11-15T23:06:19Z

From: Johannes Berg <johannes.berg@intel.com>

[ Upstream commit e864a77f51d0d8113b49cf7d030bc9dc911c8176 ]

If the data we get from EFI is not even long enough for
the package struct we expect then ignore it entirely.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Fixes: a1a6a4cf49ec ("iwlwifi: pnvm: implement reading PNVM from UEFI")
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/iwlwifi.20211016114029.33feba783518.I54a5cf33975d0330792b3d208b225d479e168f32@changeid
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/wireless/intel/iwlwifi/fw/pnvm.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/fw/pnvm.c b/drivers/net/wireless/intel/iwlwifi/fw/pnvm.c
index 512c512eefc71..24de6e5eb6a4c 100644
--- a/drivers/net/wireless/intel/iwlwifi/fw/pnvm.c
+++ b/drivers/net/wireless/intel/iwlwifi/fw/pnvm.c
@@ -284,9 +284,13 @@ int iwl_pnvm_load(struct iwl_trans *trans,
/* First attempt to get the PNVM from BIOS */
package = iwl_uefi_get_pnvm(trans, &len);
if (!IS_ERR_OR_NULL(package)) {
- /* we need only the data */
- len -= sizeof(*package);
- data = kmemdup(package->data, len, GFP_KERNEL);
+ if (len >= sizeof(*package)) {
+ /* we need only the data */
+ len -= sizeof(*package);
+ data = kmemdup(package->data, len, GFP_KERNEL);
+ } else {
+ data = NULL;
+ }

/* free package regardless of whether kmemdup succeeded */
kfree(package);
--
2.33.0