From: Johannes Berg johannes.berg@intel.com
[ Upstream commit 682b6dc29d98e857e6ca4bbc077c7dc2899b7473 ]
If the firmware sends us a corrupted MCC response with n_channels much larger than the command response can be, we might copy far too much (uninitialized) memory and even crash if the n_channels is large enough to make it run out of the one page allocated for the FW response.
Fix that by checking the lengths. Doing a < comparison would be sufficient, but the firmware should be doing it correctly, so check more strictly.
Fixes: dcaf9f5ecb6f ("iwlwifi: mvm: add MCC update FW API") Signed-off-by: Johannes Berg johannes.berg@intel.com Signed-off-by: Gregory Greenman gregory.greenman@intel.com Link: https://lore.kernel.org/r/20230514120631.d7b233139eb4.I51fd319df8e9d41881fc8... Signed-off-by: Johannes Berg johannes.berg@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/wireless/intel/iwlwifi/mvm/nvm.c | 10 ++++++++++ 1 file changed, 10 insertions(+)
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/nvm.c b/drivers/net/wireless/intel/iwlwifi/mvm/nvm.c index da705fcaf0fcc..8a9732b5b9652 100644 --- a/drivers/net/wireless/intel/iwlwifi/mvm/nvm.c +++ b/drivers/net/wireless/intel/iwlwifi/mvm/nvm.c @@ -445,6 +445,11 @@ iwl_mvm_update_mcc(struct iwl_mvm *mvm, const char *alpha2, struct iwl_mcc_update_resp *mcc_resp = (void *)pkt->data;
n_channels = __le32_to_cpu(mcc_resp->n_channels); + if (iwl_rx_packet_payload_len(pkt) != + struct_size(mcc_resp, channels, n_channels)) { + resp_cp = ERR_PTR(-EINVAL); + goto exit; + } resp_len = sizeof(struct iwl_mcc_update_resp) + n_channels * sizeof(__le32); resp_cp = kmemdup(mcc_resp, resp_len, GFP_KERNEL); @@ -456,6 +461,11 @@ iwl_mvm_update_mcc(struct iwl_mvm *mvm, const char *alpha2, struct iwl_mcc_update_resp_v3 *mcc_resp_v3 = (void *)pkt->data;
n_channels = __le32_to_cpu(mcc_resp_v3->n_channels); + if (iwl_rx_packet_payload_len(pkt) != + struct_size(mcc_resp_v3, channels, n_channels)) { + resp_cp = ERR_PTR(-EINVAL); + goto exit; + } resp_len = sizeof(struct iwl_mcc_update_resp) + n_channels * sizeof(__le32); resp_cp = kzalloc(resp_len, GFP_KERNEL);