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3 commits

Author SHA1 Message Date
Minas Harutyunyan
8b76006f7a usb: dwc2: host: Fix remote wakeup from hibernation
commit bae2bc73a59c200db53b6c15fb26bb758e2c6108 upstream.

Starting from core v4.30a changed order of programming
GPWRDN_PMUACTV to 0 in case of exit from hibernation on
remote wakeup signaling from device.

Fixes: c5c403dc4336 ("usb: dwc2: Add host/device hibernation functions")
CC: stable@vger.kernel.org
Signed-off-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Link: https://lore.kernel.org/r/99385ec55ce73445b6fbd0f471c9bd40eb1c9b9e.1708939799.git.Minas.Harutyunyan@synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-19 09:22:42 +01:00
Jia-Ju Bai
b8cc1dc6bb usb: dwc2: fix possible NULL pointer dereference caused by driver concurrency
[ Upstream commit ef307bc6ef04e8c1ea843231db58e3afaafa9fa6 ]

In _dwc2_hcd_urb_enqueue(), "urb->hcpriv = NULL" is executed without
holding the lock "hsotg->lock". In _dwc2_hcd_urb_dequeue():

    spin_lock_irqsave(&hsotg->lock, flags);
    ...
	if (!urb->hcpriv) {
		dev_dbg(hsotg->dev, "## urb->hcpriv is NULL ##\n");
		goto out;
	}
    rc = dwc2_hcd_urb_dequeue(hsotg, urb->hcpriv); // Use urb->hcpriv
    ...
out:
    spin_unlock_irqrestore(&hsotg->lock, flags);

When _dwc2_hcd_urb_enqueue() and _dwc2_hcd_urb_dequeue() are
concurrently executed, the NULL check of "urb->hcpriv" can be executed
before "urb->hcpriv = NULL". After urb->hcpriv is NULL, it can be used
in the function call to dwc2_hcd_urb_dequeue(), which can cause a NULL
pointer dereference.

This possible bug is found by an experimental static analysis tool
developed by myself. This tool analyzes the locking APIs to extract
function pairs that can be concurrently executed, and then analyzes the
instructions in the paired functions to identify possible concurrency
bugs including data races and atomicity violations. The above possible
bug is reported, when my tool analyzes the source code of Linux 6.5.

To fix this possible bug, "urb->hcpriv = NULL" should be executed with
holding the lock "hsotg->lock". After using this patch, my tool never
reports the possible bug, with the kernelconfiguration allyesconfig for
x86_64. Because I have no associated hardware, I cannot test the patch
in runtime testing, and just verify it according to the code logic.

Fixes: 33ad261aa62b ("usb: dwc2: host: spinlock urb_enqueue")
Signed-off-by: Jia-Ju Bai <baijiaju@buaa.edu.cn>
Link: https://lore.kernel.org/r/20230926024404.832096-1-baijiaju@buaa.edu.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-18 11:43:05 +01:00
Gabriel2392
7ed7ee9edf Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00