The class/subclass/protocol options are suspectible to race conditions
as they can be accessed concurrently through configfs.
Use existing mutex to protect these options. This issue was identified
during code inspection.
Fixes: 73517cf49bd4 ("usb: gadget: add RNDIS configfs options for class/subclass/protocol")
Cc: stable@vger.kernel.org
Signed-off-by: Kuen-Han Tsai <khtsai@google.com>
---
drivers/usb/gadget/function/f_rndis.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/drivers/usb/gadget/function/f_rndis.c b/drivers/usb/gadget/function/f_rndis.c
index 8b11d8d6d89c..521b4619d6be 100644
--- a/drivers/usb/gadget/function/f_rndis.c
+++ b/drivers/usb/gadget/function/f_rndis.c
@@ -11,6 +11,7 @@
/* #define VERBOSE_DEBUG */
+#include <linux/cleanup.h>
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/module.h>
@@ -678,9 +679,11 @@ rndis_bind(struct usb_configuration *c, struct usb_function *f)
return -ENOMEM;
}
- rndis_iad_descriptor.bFunctionClass = rndis_opts->class;
- rndis_iad_descriptor.bFunctionSubClass = rndis_opts->subclass;
- rndis_iad_descriptor.bFunctionProtocol = rndis_opts->protocol;
+ scoped_guard(mutex, &rndis_opts->lock) {
+ rndis_iad_descriptor.bFunctionClass = rndis_opts->class;
+ rndis_iad_descriptor.bFunctionSubClass = rndis_opts->subclass;
+ rndis_iad_descriptor.bFunctionProtocol = rndis_opts->protocol;
+ }
/*
* in drivers/usb/gadget/configfs.c:configfs_composite_bind()
--
2.53.0.959.g497ff81fa9-goog