This is a note to let you know that I've just added the patch titled
usb: gadget: Fix double free of device descriptor pointers
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
usb-gadget-fix-double-free-of-device-descriptor-pointers.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 43c4cab006f55b6ca549dd1214e22f5965a8675f Mon Sep 17 00:00:00 2001
From: Hemant Kumar <hemantk@xxxxxxxxxxxxxx>
Date: Wed, 21 Apr 2021 12:47:32 -0700
Subject: usb: gadget: Fix double free of device descriptor pointers
From: Hemant Kumar <hemantk@xxxxxxxxxxxxxx>
commit 43c4cab006f55b6ca549dd1214e22f5965a8675f upstream.
Upon driver unbind usb_free_all_descriptors() function frees all
speed descriptor pointers without setting them to NULL. In case
gadget speed changes (i.e from super speed plus to super speed)
after driver unbind only upto super speed descriptor pointers get
populated. Super speed plus desc still holds the stale (already
freed) pointer. Fix this issue by setting all descriptor pointers
to NULL after freeing them in usb_free_all_descriptors().
Fixes: f5c61225cf29 ("usb: gadget: Update function for SuperSpeedPlus")
cc: stable@xxxxxxxxxxxxxxx
Reviewed-by: Peter Chen <peter.chen@xxxxxxxxxx>
Signed-off-by: Hemant Kumar <hemantk@xxxxxxxxxxxxxx>
Signed-off-by: Wesley Cheng <wcheng@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/1619034452-17334-1-git-send-email-wcheng@xxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/gadget/config.c | 4 ++++
1 file changed, 4 insertions(+)
--- a/drivers/usb/gadget/config.c
+++ b/drivers/usb/gadget/config.c
@@ -198,9 +198,13 @@ EXPORT_SYMBOL_GPL(usb_assign_descriptors
void usb_free_all_descriptors(struct usb_function *f)
{
usb_free_descriptors(f->fs_descriptors);
+ f->fs_descriptors = NULL;
usb_free_descriptors(f->hs_descriptors);
+ f->hs_descriptors = NULL;
usb_free_descriptors(f->ss_descriptors);
+ f->ss_descriptors = NULL;
usb_free_descriptors(f->ssp_descriptors);
+ f->ssp_descriptors = NULL;
}
EXPORT_SYMBOL_GPL(usb_free_all_descriptors);
Patches currently in stable-queue which might be from hemantk@xxxxxxxxxxxxxx are
queue-4.9/usb-gadget-fix-double-free-of-device-descriptor-pointers.patch
