From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dan Carpenter Date: Fri, 18 Sep 2020 14:27:32 +0000 Subject: [PATCH] ath6kl: wmi: prevent a shift wrapping bug in ath6kl_wmi_delete_pstream_cmd() Message-Id: <20200918142732.GA909725@mwanda> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Kalle Valo Cc: Jakub Kicinski , linux-wireless@vger.kernel.org, kernel-janitors@vger.kernel.org The "tsid" is a user controlled u8 which comes from debugfs. Values more than 15 are invalid because "active_tsids" is a 16 bit variable. If the value of "tsid" is more than 31 then that leads to a shift wrapping bug. Fixes: 8fffd9e5ec9e ("ath6kl: Implement support for QOS-enable and QOS-disable from userspace") Signed-off-by: Dan Carpenter --- In the current code if the TSID bit isn't set it returns -ENODATA but returning -EINVAL here should be fine. drivers/net/wireless/ath/ath6kl/wmi.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/net/wireless/ath/ath6kl/wmi.c b/drivers/net/wireless/ath/ath6kl/wmi.c index a4339cca661f..dbc47702a268 100644 --- a/drivers/net/wireless/ath/ath6kl/wmi.c +++ b/drivers/net/wireless/ath/ath6kl/wmi.c @@ -2639,6 +2639,11 @@ int ath6kl_wmi_delete_pstream_cmd(struct wmi *wmi, u8 if_idx, u8 traffic_class, return -EINVAL; } + if (tsid >= 16) { + ath6kl_err("invalid tsid: %d\n", tsid); + return -EINVAL; + } + skb = ath6kl_wmi_get_new_buf(sizeof(*cmd)); if (!skb) return -ENOMEM; -- 2.28.0