[PATCH] wifi: ath12k: Fix buffer overflow in debugfs

[Dan Carpenter]

If the user tries to write more than 32 bytes then it results in memory
corruption.  Fortunately, this is debugfs so it's limitted to root users.

Fixes: 3f73c24f28b3 ("wifi: ath12k: Add support to enable debugfs_htt_stats")
Signed-off-by: Dan Carpenter <dan.carpenter at linaro.org>
---
 drivers/net/wireless/ath/ath12k/debugfs_htt_stats.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/wireless/ath/ath12k/debugfs_htt_stats.c b/drivers/net/wireless/ath/ath12k/debugfs_htt_stats.c
index 1c0d5fa39a8d..aeaf970339d4 100644
--- a/drivers/net/wireless/ath/ath12k/debugfs_htt_stats.c
+++ b/drivers/net/wireless/ath/ath12k/debugfs_htt_stats.c
@@ -5377,6 +5377,9 @@ static ssize_t ath12k_write_htt_stats_type(struct file *file,
 	const int size = 32;
 	int num_args;
 
+	if (count > size)
+		return -EINVAL;
+
 	char *buf __free(kfree) = kzalloc(size, GFP_KERNEL);
 	if (!buf)
 		return -ENOMEM;
-- 
2.47.2