3.16.62-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Ben Hutchings <ben.hutchi...@codethink.co.uk>

commit 7e10f14ebface44a48275c8d6dc1caae3668d5a9 upstream.

If the written data starts with a digit, yurex_write() tries to parse
it as an integer using simple_strtoull().  This requires a null-
terminator, and currently there's no guarantee that there is one.

(The sample program at
https://github.com/NeoCat/YUREX-driver-for-Linux/blob/master/sample/yurex_clock.pl
writes an integer without a null terminator.  It seems like it must
have worked by chance!)

Always add a null byte after the written data.  Enlarge the buffer
to allow for this.

Signed-off-by: Ben Hutchings <ben.hutchi...@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <b...@decadent.org.uk>
---
 drivers/usb/misc/yurex.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

--- a/drivers/usb/misc/yurex.c
+++ b/drivers/usb/misc/yurex.c
@@ -437,13 +437,13 @@ static ssize_t yurex_write(struct file *
 {
        struct usb_yurex *dev;
        int i, set = 0, retval = 0;
-       char buffer[16];
+       char buffer[16 + 1];
        char *data = buffer;
        unsigned long long c, c2 = 0;
        signed long timeout = 0;
        DEFINE_WAIT(wait);
 
-       count = min(sizeof(buffer), count);
+       count = min(sizeof(buffer) - 1, count);
        dev = (struct usb_yurex *)file->private_data;
 
        /* verify that we actually have some data to write */
@@ -462,6 +462,7 @@ static ssize_t yurex_write(struct file *
                retval = -EFAULT;
                goto error;
        }
+       buffer[count] = 0;
        memset(dev->cntl_buffer, CMD_PADDING, YUREX_BUF_SIZE);
 
        switch (buffer[0]) {

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