wifi: iwlwifi: Track scan_cmd allocation size explicitly

In preparation for reducing the use of ksize(), explicitly track the
size of scan_cmd allocations. This also allows for noticing if the scan
size changes unexpectedly. Note that using ksize() was already incorrect
here, in the sense that ksize() would not match the actual allocation
size, which would trigger future run-time allocation bounds checking.
(In other words, memset() may know how large scan_cmd was allocated for,
but ksize() will return the upper bounds of the actually allocated memory,
causing a run-time warning about an overflow.)

Cc: Gregory Greenman <[email protected]>
Cc: Kalle Valo <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Eric Dumazet <[email protected]>
Cc: Jakub Kicinski <[email protected]>
Cc: Paolo Abeni <[email protected]>
Cc: Luca Coelho <[email protected]>
Cc: Johannes Berg <[email protected]>
Cc: Emmanuel Grumbach <[email protected]>
Cc: Miri Korenblit <[email protected]>
Cc: Ilan Peer <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Kees Cook <[email protected]>
Signed-off-by: Kalle Valo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/ops.c b/drivers/net/wireless/intel/iwlwifi/mvm/ops.c
index 429963cd8ee1..d2d42cd48af2 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/ops.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/ops.c
@@ -1076,7 +1076,7 @@ iwl_op_mode_mvm_start(struct iwl_trans *trans, const struct iwl_cfg *cfg,
 	static const u8 no_reclaim_cmds[] = {
 		TX_CMD,
 	};
-	int scan_size;
+	size_t scan_size;
 	u32 min_backoff;
 	struct iwl_mvm_csme_conn_info *csme_conn_info __maybe_unused;
 
@@ -1303,6 +1303,7 @@ iwl_op_mode_mvm_start(struct iwl_trans *trans, const struct iwl_cfg *cfg,
 	mvm->scan_cmd = kmalloc(scan_size, GFP_KERNEL);
 	if (!mvm->scan_cmd)
 		goto out_free;
+	mvm->scan_cmd_size = scan_size;
 
 	/* invalidate ids to prevent accidental removal of sta_id 0 */
 	mvm->aux_sta.sta_id = IWL_MVM_INVALID_STA;