CVE-2024-49929

In the Linux kernel, the following vulnerability has been resolved:

wifi: iwlwifi: mvm: avoid NULL pointer dereference

iwl_mvm_tx_skb_sta() and iwl_mvm_tx_mpdu() verify that the mvmvsta
pointer is not NULL.
It retrieves this pointer using iwl_mvm_sta_from_mac80211, which is
dereferencing the ieee80211_sta pointer.
If sta is NULL, iwl_mvm_sta_from_mac80211 will dereference a NULL
pointer.
Fix this by checking the sta pointer before retrieving the mvmsta
from it. If sta is not NULL, then mvmsta isn't either.