linux-kernel - [PATCH for v4.9 LTS 27/87] usb: dwc3: omap: fix race of pm runtime with irq handler in probe

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Sat, 15 Jul 2017 01:26:06 +0000
From:   "Levin, Alexander (Sasha Levin)" <alexander.levin@...izon.com>
To:     "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "stable@...r.kernel.org" <stable@...r.kernel.org>
Cc:     Grygorii Strashko <grygorii.strashko@...com>,
        Felipe Balbi <felipe.balbi@...ux.intel.com>,
        "Levin, Alexander (Sasha Levin)" <alexander.levin@...izon.com>
Subject: [PATCH for v4.9 LTS 27/87] usb: dwc3: omap: fix race of pm runtime
 with irq handler in probe

From: Grygorii Strashko <grygorii.strashko@...com>

[ Upstream commit 12a7f17fac5b370bec87259e4c718faf563ce900 ]

Now races can happen between interrupt handler execution and PM runtime in
error handling code path in probe and in dwc3_omap_remove() which will lead
to system crash:

in probe:
...
 err1:
	pm_runtime_put_sync(dev);
^^ PM runtime can race with IRQ handler when deferred probing happening
   due to extcon
	pm_runtime_disable(dev);

	return ret;

in dwc3_omap_remove:
...
	dwc3_omap_disable_irqs(omap);
^^ IRQs are disabled in HW, but handler may still run
	of_platform_depopulate(omap->dev);
	pm_runtime_put_sync(&pdev->dev);
^^ PM runtime can race with IRQ handler
	pm_runtime_disable(&pdev->dev);

	return 0;

So, OMAP DWC3 IRQ need to be disabled before calling
pm_runtime_put() in probe and in dwc3_omap_remove().

Acked-by: Tony Lindgren <tony@...mide.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@...com>
Signed-off-by: Felipe Balbi <felipe.balbi@...ux.intel.com>
Signed-off-by: Sasha Levin <alexander.levin@...izon.com>
---
 drivers/usb/dwc3/dwc3-omap.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/dwc3/dwc3-omap.c b/drivers/usb/dwc3/dwc3-omap.c
index 5dd1832564c7..35b63518baf6 100644
--- a/drivers/usb/dwc3/dwc3-omap.c
+++ b/drivers/usb/dwc3/dwc3-omap.c
@@ -19,6 +19,7 @@
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/slab.h>
+#include <linux/irq.h>
 #include <linux/interrupt.h>
 #include <linux/platform_device.h>
 #include <linux/platform_data/dwc3-omap.h>
@@ -511,7 +512,7 @@ static int dwc3_omap_probe(struct platform_device *pdev)
 
 	/* check the DMA Status */
 	reg = dwc3_omap_readl(omap->base, USBOTGSS_SYSCONFIG);
-
+	irq_set_status_flags(omap->irq, IRQ_NOAUTOEN);
 	ret = devm_request_threaded_irq(dev, omap->irq, dwc3_omap_interrupt,
 					dwc3_omap_interrupt_thread, IRQF_SHARED,
 					"dwc3-omap", omap);
@@ -532,7 +533,7 @@ static int dwc3_omap_probe(struct platform_device *pdev)
 	}
 
 	dwc3_omap_enable_irqs(omap);
-
+	enable_irq(omap->irq);
 	return 0;
 
 err2:
@@ -553,6 +554,7 @@ static int dwc3_omap_remove(struct platform_device *pdev)
 	extcon_unregister_notifier(omap->edev, EXTCON_USB, &omap->vbus_nb);
 	extcon_unregister_notifier(omap->edev, EXTCON_USB_HOST, &omap->id_nb);
 	dwc3_omap_disable_irqs(omap);
+	disable_irq(omap->irq);
 	of_platform_depopulate(omap->dev);
 	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
-- 
2.11.0