USB: usbtmc: inhibit corruption
Limit data copied to userspace to amount requested. Prevents a faulty
instrument from overwriting user memory.
Signed-off-by: Steve Holland <sdh4@iastate.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c
index f2fde7c..91d3a94 100644
--- a/drivers/usb/class/usbtmc.c
+++ b/drivers/usb/class/usbtmc.c
@@ -473,6 +473,10 @@
n_characters = this_part;
}
+ /* Bound amount of data received by amount of data requested */
+ if (n_characters > this_part)
+ n_characters = this_part;
+
/* Copy buffer to user space */
if (copy_to_user(buf + done, &buffer[12], n_characters)) {
/* There must have been an addressing problem */
