wifi: ath12k: fix possible out-of-bound read in ath12k_htt_pull_ppdu_stats()

[ Upstream commit 1bc44a505a229bb1dd4957e11aa594edeea3690e ]

len is extracted from HTT message and could be an unexpected value in
case errors happen, so add validation before using to avoid possible
out-of-bound read in the following message iteration and parsing.

The same issue also applies to ppdu_info->ppdu_stats.common.num_users,
so validate it before using too.

These are found during code review.

Compile test only.

Signed-off-by: Baochen Qiang <quic_bqiang@quicinc.com>
Acked-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20230901015602.45112-1-quic_bqiang@quicinc.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/wireless/ath/ath12k/dp_rx.c b/drivers/net/wireless/ath/ath12k/dp_rx.c
index 690a010..e1c84fc 100644 (file)
--- a/drivers/net/wireless/ath/ath12k/dp_rx.c
+++ b/drivers/net/wireless/ath/ath12k/dp_rx.c
@@ -1555,6 +1555,13 @@ static int ath12k_htt_pull_ppdu_stats(struct ath12k_base *ab,
 
        msg = (struct ath12k_htt_ppdu_stats_msg *)skb->data;
        len = le32_get_bits(msg->info, HTT_T2H_PPDU_STATS_INFO_PAYLOAD_SIZE);
+       if (len > (skb->len - struct_size(msg, data, 0))) {
+               ath12k_warn(ab,
+                           "HTT PPDU STATS event has unexpected payload size %u, should be smaller than %u\n",
+                           len, skb->len);
+               return -EINVAL;
+       }
+
        pdev_id = le32_get_bits(msg->info, HTT_T2H_PPDU_STATS_INFO_PDEV_ID);
        ppdu_id = le32_to_cpu(msg->ppdu_id);
 
@@ -1583,6 +1590,16 @@ static int ath12k_htt_pull_ppdu_stats(struct ath12k_base *ab,
                goto exit;
        }
 
+       if (ppdu_info->ppdu_stats.common.num_users >= HTT_PPDU_STATS_MAX_USERS) {
+               spin_unlock_bh(&ar->data_lock);
+               ath12k_warn(ab,
+                           "HTT PPDU STATS event has unexpected num_users %u, should be smaller than %u\n",
+                           ppdu_info->ppdu_stats.common.num_users,
+                           HTT_PPDU_STATS_MAX_USERS);
+               ret = -EINVAL;
+               goto exit;
+       }
+
        /* back up data rate tlv for all peers */
        if (ppdu_info->frame_type == HTT_STATS_PPDU_FTYPE_DATA &&
            (ppdu_info->tlv_bitmap & (1 << HTT_PPDU_STATS_TAG_USR_COMMON)) &&