[PATCH v2 2/6] wifi: mwifiex: fix OOB write from firmware TID in ADDBA response handler

[Tristan Madani <tristmd@gmail.com>]

From: Tristan Madani <tristan@talencesecurity.com>

The TID value extracted from the Block Ack parameter set is a 4-bit
field (0-15), but aggr_prio_tbl[] has only 8 entries. A TID >= 8 causes
an out-of-bounds write to adjacent struct mwifiex_private fields.

Add a bounds check after extracting the TID.

Fixes: 5e6e3a92b9a4 ("wireless: mwifiex: initial commit for Marvell mwifiex driver")
Signed-off-by: Tristan Madani <tristan@talencesecurity.com>
---
drivers/net/wireless/marvell/mwifiex/11n.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/net/wireless/marvell/mwifiex/11n.c b/drivers/net/wireless/marvell/mwifiex/11n.c
index XXXXXXX..XXXXXXX 100644
--- a/drivers/net/wireless/marvell/mwifiex/11n.c
+++ b/drivers/net/wireless/marvell/mwifiex/11n.c
@@ -155,6 +155,11 @@ int mwifiex_ret_11n_addba_req(struct mwifiex_private *priv,
 	tid = (block_ack_param_set & IEEE80211_ADDBA_PARAM_TID_MASK)
 	       >> BLOCKACKPARAM_TID_POS;

+	if (tid >= MAX_NUM_TID) {
+		mwifiex_dbg(priv->adapter, ERROR,
+			    "ADDBA RSP: invalid tid %d\n", tid);
+		return -EINVAL;
+	}
 	tid_down = mwifiex_wmm_downgrade_tid(priv, tid);
 	ra_list = mwifiex_wmm_get_ralist_node(priv, tid_down, add_ba_rsp->
 		peer_mac_addr);