On 8/31/19 2:18 PM, Guenter Roeck wrote:

On Mon, Aug 19, 2019 at 06:02:29PM -0400, Hui Peng wrote:

quoted

`dev` (struct rsi_91x_usbdev *) field of adapter
(struct rsi_91x_usbdev *) is allocated  and initialized in
`rsi_init_usb_interface`. If any error is detected in information
read from the device side,  `rsi_init_usb_interface` will be
freed. However, in the higher level error handling code in
`rsi_probe`, if error is detected, `rsi_91x_deinit` is called
again, in which `dev` will be freed again, resulting double free.

This patch fixes the double free by removing the free operation on
`dev` in `rsi_init_usb_interface`, because `rsi_91x_deinit` is also
used in `rsi_disconnect`, in that code path, the `dev` field is not
 (and thus needs to be) freed.

This bug was found in v4.19, but is also present in the latest version
of kernel.

Reported-by: Hui Peng <redacted>
Reported-by: Mathias Payer <redacted>
Signed-off-by: Hui Peng <redacted>

FWIW:

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

This patch is listed as fix for CVE-2019-15504, which has a CVSS 2.0 score
of 10.0 (high) and CVSS 3.0 score of 9.8 (critical).

Are there any plans to apply this patch to the upstream kernel anytime
soon ? If not, are there reasons to believe that the problem is not as
severe as its CVSS score may indicate ?

This patch is also still under review.

Thanks,
Guenter

quoted

---
 drivers/net/wireless/rsi/rsi_91x_usb.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/net/wireless/rsi/rsi_91x_usb.c b/drivers/net/wireless/rsi/rsi_91x_usb.c
index c0a163e40402..ac917227f708 100644
--- a/drivers/net/wireless/rsi/rsi_91x_usb.c
+++ b/drivers/net/wireless/rsi/rsi_91x_usb.c

@@ -640,7 +640,6 @@ static int rsi_init_usb_interface(struct rsi_hw *adapter,
 	kfree(rsi_dev->tx_buffer);
 
 fail_eps:
-	kfree(rsi_dev);
 
 	return status;
 }

-- 
2.22.1