2023-06-20 10:08:39

by Greenman, Gregory

[permalink] [raw]
Subject: [PATCH 16/19] wifi: iwlwifi: mvm: avoid baid size integer overflow

From: Johannes Berg <[email protected]>

Roee reported various hard-to-debug crashes with pings in
EHT aggregation scenarios. Enabling KASAN showed that we
access the BAID allocation out of bounds, and looking at
the code a bit shows that since the reorder buffer entry
(struct iwl_mvm_reorder_buf_entry) is 128 bytes if debug
such as lockdep is enabled, then staring from an agg size
512 we overflow the size calculation, and allocate a much
smaller structure than we should, causing slab corruption
once we initialize this.

Fix this by simply using u32 instead of u16.

Reported-by: Roee Goldfiner <[email protected]>
Signed-off-by: Johannes Berg <[email protected]>
Signed-off-by: Gregory Greenman <[email protected]>
---
drivers/net/wireless/intel/iwlwifi/mvm/sta.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
index 37a52ffa8897..3b9a343d4f67 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
@@ -2885,7 +2885,7 @@ int iwl_mvm_sta_rx_agg(struct iwl_mvm *mvm, struct ieee80211_sta *sta,
}

if (iwl_mvm_has_new_rx_api(mvm) && start) {
- u16 reorder_buf_size = buf_size * sizeof(baid_data->entries[0]);
+ u32 reorder_buf_size = buf_size * sizeof(baid_data->entries[0]);

/* sparse doesn't like the __align() so don't check */
#ifndef __CHECKER__
--
2.38.1