2021-03-17 12:19:30

by Lee Gibson

Subject: [PATCH] wl1251: Fix possible buffer overflow in wl1251_cmd_scan

Function wl1251_cmd_scan calls memcpy without checking the length.
A user could control that length and trigger a buffer overflow.
Fix by checking the length is within the maximum allowed size.

Signed-off-by: Lee Gibson <[email protected]>
---
drivers/net/wireless/ti/wl1251/cmd.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/ti/wl1251/cmd.c b/drivers/net/wireless/ti/wl1251/cmd.c
index 498c8db2eb48..e4d028a53d91 100644
--- a/drivers/net/wireless/ti/wl1251/cmd.c
+++ b/drivers/net/wireless/ti/wl1251/cmd.c
@@ -455,8 +455,11 @@ int wl1251_cmd_scan(struct wl1251 *wl, u8 *ssid, size_t ssid_len,
}

cmd->params.ssid_len = ssid_len;
- if (ssid)
- memcpy(cmd->params.ssid, ssid, ssid_len);
+ if (ssid) {
+ int len = min_t(int, ssid_len, IEEE80211_MAX_SSID_LEN);
+
+ memcpy(cmd->params.ssid, ssid, len);
+ }

ret = wl1251_cmd_send(wl, CMD_SCAN, cmd, sizeof(*cmd));
if (ret < 0) {
--
2.25.1

2021-04-28 11:56:02

by Lee Gibson

Subject: [PATCH v2] wl1251: Fix possible buffer overflow in wl1251_cmd_scan

Function wl1251_cmd_scan calls memcpy without checking the length.
Harden by checking the length is within the maximum allowed size.

Signed-off-by: Lee Gibson <[email protected]>
---
v2: use clamp_val() instead of min_t()

drivers/net/wireless/ti/wl1251/cmd.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/ti/wl1251/cmd.c b/drivers/net/wireless/ti/wl1251/cmd.c
index 498c8db2eb48..d7a869106782 100644
--- a/drivers/net/wireless/ti/wl1251/cmd.c
+++ b/drivers/net/wireless/ti/wl1251/cmd.c
@@ -454,9 +454,12 @@ int wl1251_cmd_scan(struct wl1251 *wl, u8 *ssid, size_t ssid_len,
cmd->channels[i].channel = channels[i]->hw_value;
}

- cmd->params.ssid_len = ssid_len;
- if (ssid)
- memcpy(cmd->params.ssid, ssid, ssid_len);
+ if (ssid) {
+ int len = clamp_val(ssid_len, 0, IEEE80211_MAX_SSID_LEN);
+
+ cmd->params.ssid_len = len;
+ memcpy(cmd->params.ssid, ssid, len);
+ }

ret = wl1251_cmd_send(wl, CMD_SCAN, cmd, sizeof(*cmd));
if (ret < 0) {
--
2.25.1

2021-06-15 13:37:08

by Kalle Valo

Subject: Re: [PATCH v2] wl1251: Fix possible buffer overflow in wl1251_cmd_scan

Lee Gibson <[email protected]> wrote:

> Function wl1251_cmd_scan calls memcpy without checking the length.
> Harden by checking the length is within the maximum allowed size.
>
> Signed-off-by: Lee Gibson <[email protected]>

Patch applied to wireless-drivers-next.git, thanks.

d10a87a3535c wl1251: Fix possible buffer overflow in wl1251_cmd_scan

--
https://patchwork.kernel.org/project/linux-wireless/patch/[email protected]/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches