4.19-stable review patch. If anyone has any objections, please let me know.
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From: Oliver Neukum oneukum@suse.com
commit 49cd2f4d747eeb3050b76245a7f72aa99dbd3310 upstream.
As we process the second byte of a control transfer, transfers of less than 2 bytes must be discarded.
This bug is as old as the driver.
SIgned-off-by: Oliver Neukum oneukum@suse.com CC: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240912125449.1030536-1-oneukum@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/misc/cypress_cy7c63.c | 4 ++++ 1 file changed, 4 insertions(+)
--- a/drivers/usb/misc/cypress_cy7c63.c +++ b/drivers/usb/misc/cypress_cy7c63.c @@ -88,6 +88,9 @@ static int vendor_command(struct cypress USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_OTHER, address, data, iobuf, CYPRESS_MAX_REQSIZE, USB_CTRL_GET_TIMEOUT); + /* we must not process garbage */ + if (retval < 2) + goto err_buf;
/* store returned data (more READs to be added) */ switch (request) { @@ -107,6 +110,7 @@ static int vendor_command(struct cypress break; }
+err_buf: kfree(iobuf); error: return retval;