From 43c4cab006f55b6ca549dd1214e22f5965a8675f Mon Sep 17 00:00:00 2001
From: Hemant Kumar <hemantk@codeaurora.org>
Date: Wed, 21 Apr 2021 12:47:32 -0700
Subject: [PATCH] usb: gadget: Fix double free of device descriptor pointers
Git-commit: 43c4cab006f55b6ca549dd1214e22f5965a8675f
Patch-mainline: v5.13-rc1
References: git-fixes

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@vger.kernel.org
Reviewed-by: Peter Chen <peter.chen@kernel.org>
Signed-off-by: Hemant Kumar <hemantk@codeaurora.org>
Signed-off-by: Wesley Cheng <wcheng@codeaurora.org>
Link: https://lore.kernel.org/r/1619034452-17334-1-git-send-email-wcheng@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/usb/gadget/config.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/usb/gadget/config.c b/drivers/usb/gadget/config.c
index 2d115353424c..8bb25773b61e 100644
--- a/drivers/usb/gadget/config.c
+++ b/drivers/usb/gadget/config.c
@@ -194,9 +194,13 @@ 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);
 
-- 
2.26.2