[PATCH 2/3] net: phy: fixed_phy: fix use-after-free when checking link GPIO
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Date: 2019-10-04 23:14:13
Also in:
lkml
Subsystem:
ethernet phy library, networking drivers, the rest · Maintainers:
Andrew Lunn, Heiner Kallweit, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
If we fail to locate GPIO for any reason other than deferral or not-found-GPIO, we try to print device tree node info, however if might be freed already as we called of_node_put() on it. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> --- drivers/net/phy/fixed_phy.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-)
diff --git a/drivers/net/phy/fixed_phy.c b/drivers/net/phy/fixed_phy.c
index 7c5265fd2b94..4190f9ed5313 100644
--- a/drivers/net/phy/fixed_phy.c
+++ b/drivers/net/phy/fixed_phy.c@@ -212,16 +212,13 @@ static struct gpio_desc *fixed_phy_get_gpiod(struct device_node *np) */ gpiod = gpiod_get_from_of_node(fixed_link_node, "link-gpios", 0, GPIOD_IN, "mdio"); - of_node_put(fixed_link_node); - if (IS_ERR(gpiod)) { - if (PTR_ERR(gpiod) == -EPROBE_DEFER) - return gpiod; - + if (IS_ERR(gpiod) && PTR_ERR(gpiod) != -EPROBE_DEFER) { if (PTR_ERR(gpiod) != -ENOENT) pr_err("error getting GPIO for fixed link %pOF, proceed without\n", fixed_link_node); gpiod = NULL; } + of_node_put(fixed_link_node); return gpiod; }
--
2.23.0.581.g78d2f28ef7-goog