Re: [PATCH v2] phy: tegra: xusb: Fix use-after-free issue

From: Jon Hunter
Date: Tue Jun 06 2023 - 05:40:45 EST


Hi Vinod,

On 08/05/2023 11:03, Haotien Hsu wrote:
From: EJ Hsu <ejh@xxxxxxxxxx>

For the dual-role port, it will assign the phy dev to usb-phy dev and
use the port dev driver as the dev driver of usb-phy.

When we try to destroy the port dev, it will destroy its dev driver
as well. But we did not remove the reference from usb-phy dev. This
might cause the use-after-free issue in KASAN.

Fixes: e8f7d2f409a1 ("phy: tegra: xusb: Add usb-phy support")
Cc: stable@xxxxxxxxxxxxxxx

Signed-off-by: EJ Hsu <ejh@xxxxxxxxxx>
Signed-off-by: Haotien Hsu <haotienh@xxxxxxxxxx>
---
V1 -> V2: Remove extra movements to clarify the change
---
drivers/phy/tegra/xusb.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/phy/tegra/xusb.c b/drivers/phy/tegra/xusb.c
index 78045bd6c214..26b66a668f3b 100644
--- a/drivers/phy/tegra/xusb.c
+++ b/drivers/phy/tegra/xusb.c
@@ -568,6 +568,7 @@ static void tegra_xusb_port_unregister(struct tegra_xusb_port *port)
usb_role_switch_unregister(port->usb_role_sw);
cancel_work_sync(&port->usb_phy_work);
usb_remove_phy(&port->usb_phy);
+ port->usb_phy.dev->driver = NULL;
}
if (port->ops->remove)


Are you OK to pick this up now?

FWIW ...

Acked-by: Jon Hunter <jonathanh@xxxxxxxxxx>

I believe Thierry already ACK'ed V1.

Jon

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