Blob Blame History Raw
From 72035f4954f0bca2d8c47cf31b3629c42116f5b7 Mon Sep 17 00:00:00 2001
From: Tong Zhang <ztong0001@gmail.com>
Date: Wed, 17 Mar 2021 19:04:00 -0400
Subject: [PATCH] usb: gadget: udc: amd5536udc_pci fix null-ptr-dereference
Git-commit: 72035f4954f0bca2d8c47cf31b3629c42116f5b7
Patch-mainline: v5.12-rc6
References: git-fixes

init_dma_pools() calls dma_pool_create(...dev->dev) to create dma pool.
however, dev->dev is actually set after calling init_dma_pools(), which
effectively makes dma_pool_create(..NULL) and cause crash.
To fix this issue, init dma only after dev->dev is set.

[    1.317993] RIP: 0010:dma_pool_create+0x83/0x290
[    1.323257] Call Trace:
[    1.323390]  ? pci_write_config_word+0x27/0x30
[    1.323626]  init_dma_pools+0x41/0x1a0 [snps_udc_core]
[    1.323899]  udc_pci_probe+0x202/0x2b1 [amd5536udc_pci]

Fixes: 7c51247a1f62 (usb: gadget: udc: Provide correct arguments for 'dma_pool_create')
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Tong Zhang <ztong0001@gmail.com>
Link: https://lore.kernel.org/r/20210317230400.357756-1-ztong0001@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/usb/gadget/udc/amd5536udc_pci.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/gadget/udc/amd5536udc_pci.c b/drivers/usb/gadget/udc/amd5536udc_pci.c
index 8d387e0e4d91..c80f9bd51b75 100644
--- a/drivers/usb/gadget/udc/amd5536udc_pci.c
+++ b/drivers/usb/gadget/udc/amd5536udc_pci.c
@@ -153,6 +153,11 @@ static int udc_pci_probe(
 	pci_set_master(pdev);
 	pci_try_set_mwi(pdev);
 
+	dev->phys_addr = resource;
+	dev->irq = pdev->irq;
+	dev->pdev = pdev;
+	dev->dev = &pdev->dev;
+
 	/* init dma pools */
 	if (use_dma) {
 		retval = init_dma_pools(dev);
@@ -160,11 +165,6 @@ static int udc_pci_probe(
 			goto err_dma;
 	}
 
-	dev->phys_addr = resource;
-	dev->irq = pdev->irq;
-	dev->pdev = pdev;
-	dev->dev = &pdev->dev;
-
 	/* general probing */
 	if (udc_probe(dev)) {
 		retval = -ENODEV;
-- 
2.26.2