[PATCH] phy: rockchip: inno-usb2: Fix a double free bug in rockchip_usb2phy_probe()

[PATCH] phy: rockchip: inno-usb2: Fix a double free bug in rockchip_usb2phy_probe()

[Wentao Liang]

The for_each_available_child_of_node() calls of_node_put() to
release child_np in each success loop. After breaking from the
loop with the child_np has been released, the code will jump to
the put_child label and will call the of_node_put() again if the
devm_request_threaded_irq() fails. These cause a double free bug.

Fix by using a separate label to avoid the duplicate of_node_put().

Fixes: ed2b5a8e6b98 ("phy: phy-rockchip-inno-usb2: support muxed interrupts")
Cc: stable@vger.kernel.org
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
---
 drivers/phy/rockchip/phy-rockchip-inno-usb2.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/phy/rockchip/phy-rockchip-inno-usb2.c b/drivers/phy/rockchip/phy-rockchip-inno-usb2.c
index b0f23690ec30..f754c3b1c357 100644
--- a/drivers/phy/rockchip/phy-rockchip-inno-usb2.c
+++ b/drivers/phy/rockchip/phy-rockchip-inno-usb2.c
@@ -1491,7 +1491,7 @@ static int rockchip_usb2phy_probe(struct platform_device *pdev)
 						rphy);
 		if (ret) {
 			dev_err_probe(rphy->dev, ret, "failed to request usb2phy irq handle\n");
-			goto put_child;
+			goto ret_error;
 		}
 	}
 
@@ -1499,6 +1499,7 @@ static int rockchip_usb2phy_probe(struct platform_device *pdev)
 
 put_child:
 	of_node_put(child_np);
+ret_error:
 	return ret;
 }
 
-- 
2.34.1

Re: [PATCH] phy: rockchip: inno-usb2: Fix a double free bug in rockchip_usb2phy_probe()

[Markus Elfring]

…
> Fix by using a separate label to avoid the duplicate of_node_put().

May you return directly?
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/coding-style.rst?h=v6.19-rc2#n532


See also once more:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/submitting-patches.rst?h=v6.19-rc2#n659

Regards,
Markus