ath11k: fix htt stats module not handle multiple skbs

HTT EXT stats comes in stream of TLVs spanning over multiple
messages. Currently completion is being sent for each message
which is creating a race where stats_req is being accessed
for filling in second message after the memory is already
freed in release operation. Fix this by issuing completion
once all the messages are received and processed. Driver
knows this info from DONE bit set in htt msg.

Also fix locking required for htt stats.

Co-developed-by: Miles Hu <milehu@codeaurora.org>
Signed-off-by: Miles Hu <milehu@codeaurora.org>
Signed-off-by: Pradeep Kumar Chitrapu <pradeepc@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1589221074-28778-1-git-send-email-pradeepc@codeaurora.org

diff --git a/drivers/net/wireless/ath/ath11k/debug_htt_stats.c b/drivers/net/wireless/ath/ath11k/debug_htt_stats.c
index 5db0c27de4753ecf68f92a26f2763252d47dd5b0..6b532dc99c981273ce2168500ff349d652375e5a 100644 (file)
--- a/drivers/net/wireless/ath/ath11k/debug_htt_stats.c
+++ b/drivers/net/wireless/ath/ath11k/debug_htt_stats.c
@@ -4306,6 +4306,7 @@ void ath11k_dbg_htt_ext_stats_handler(struct ath11k_base *ab,
        u32 len;
        u64 cookie;
        int ret;
+       bool send_completion = false;
        u8 pdev_id;
 
        msg = (struct ath11k_htt_extd_stats_msg *)skb->data;
@@ -4330,11 +4331,11 @@ void ath11k_dbg_htt_ext_stats_handler(struct ath11k_base *ab,
                return;
 
        spin_lock_bh(&ar->debug.htt_stats.lock);
-       if (stats_req->done) {
-               spin_unlock_bh(&ar->debug.htt_stats.lock);
-               return;
-       }
-       stats_req->done = true;
+
+       stats_req->done = FIELD_GET(HTT_T2H_EXT_STATS_INFO1_DONE, msg->info1);
+       if (stats_req->done)
+               send_completion = true;
+
        spin_unlock_bh(&ar->debug.htt_stats.lock);
 
        len = FIELD_GET(HTT_T2H_EXT_STATS_INFO1_LENGTH, msg->info1);
@@ -4344,7 +4345,8 @@ void ath11k_dbg_htt_ext_stats_handler(struct ath11k_base *ab,
        if (ret)
                ath11k_warn(ab, "Failed to parse tlv %d\n", ret);
 
-       complete(&stats_req->cmpln);
+       if (send_completion)
+               complete(&stats_req->cmpln);
 }
 
 static ssize_t ath11k_read_htt_stats_type(struct file *file,
@@ -4497,28 +4499,54 @@ static int ath11k_open_htt_stats(struct inode *inode, struct file *file)
        if (type == ATH11K_DBG_HTT_EXT_STATS_RESET)
                return -EPERM;
 
+       mutex_lock(&ar->conf_mutex);
+
+       if (ar->state != ATH11K_STATE_ON) {
+               ret = -ENETDOWN;
+               goto err_unlock;
+       }
+
+       if (ar->debug.htt_stats.stats_req) {
+               ret = -EAGAIN;
+               goto err_unlock;
+       }
+
        stats_req = vzalloc(sizeof(*stats_req) + ATH11K_HTT_STATS_BUF_SIZE);
-       if (!stats_req)
-               return -ENOMEM;
+       if (!stats_req) {
+               ret = -ENOMEM;
+               goto err_unlock;
+       }
 
-       mutex_lock(&ar->conf_mutex);
        ar->debug.htt_stats.stats_req = stats_req;
        stats_req->type = type;
+
        ret = ath11k_dbg_htt_stats_req(ar);
-       mutex_unlock(&ar->conf_mutex);
        if (ret < 0)
                goto out;
 
        file->private_data = stats_req;
+
+       mutex_unlock(&ar->conf_mutex);
+
        return 0;
 out:
        vfree(stats_req);
+       ar->debug.htt_stats.stats_req = NULL;
+err_unlock:
+       mutex_unlock(&ar->conf_mutex);
+
        return ret;
 }
 
 static int ath11k_release_htt_stats(struct inode *inode, struct file *file)
 {
+       struct ath11k *ar = inode->i_private;
+
+       mutex_lock(&ar->conf_mutex);
        vfree(file->private_data);
+       ar->debug.htt_stats.stats_req = NULL;
+       mutex_unlock(&ar->conf_mutex);
+
        return 0;
 }
 

diff --git a/drivers/net/wireless/ath/ath11k/dp.h b/drivers/net/wireless/ath/ath11k/dp.h
index 222de10e4b931667cad17674baab707183451c43..058a5c1d86ffc9cbb7ae6a166eeef5a9f7b3380a 100644 (file)
--- a/drivers/net/wireless/ath/ath11k/dp.h
+++ b/drivers/net/wireless/ath/ath11k/dp.h
@@ -1517,6 +1517,7 @@ struct htt_ext_stats_cfg_params {
  *       4 bytes.
  */
 
+#define HTT_T2H_EXT_STATS_INFO1_DONE   BIT(11)
 #define HTT_T2H_EXT_STATS_INFO1_LENGTH   GENMASK(31, 16)
 
 struct ath11k_htt_extd_stats_msg {