From 42cd402b8fd4672b692400fe5f9eecd55d2794ac Mon Sep 17 00:00:00 2001 From: Krzysztof Kozlowski Date: Tue, 19 Apr 2022 13:34:35 +0200 Subject: [PATCH] rpmsg: Fix kfree() of static memory on setting driver_override The driver_override field from platform driver should not be initialized from static memory (string literal) because the core later kfree() it, for example when driver_override is set via sysfs. Use dedicated helper to set driver_override properly. Fixes: 950a7388f02b ("rpmsg: Turn name service into a stand alone driver") Fixes: c0cdc19f84a4 ("rpmsg: Driver for user space endpoint interface") Reviewed-by: Bjorn Andersson Signed-off-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20220419113435.246203-13-krzysztof.kozlowski@linaro.org Signed-off-by: Greg Kroah-Hartman --- drivers/rpmsg/rpmsg_internal.h | 15 ++++++++++++--- drivers/rpmsg/rpmsg_ns.c | 14 ++++++++++++-- include/linux/rpmsg.h | 6 ++++-- 3 files changed, 28 insertions(+), 7 deletions(-) diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h index d4b23fd019a8..3e81642238d2 100644 --- a/drivers/rpmsg/rpmsg_internal.h +++ b/drivers/rpmsg/rpmsg_internal.h @@ -94,10 +94,19 @@ int rpmsg_release_channel(struct rpmsg_device *rpdev, */ static inline int rpmsg_ctrldev_register_device(struct rpmsg_device *rpdev) { - strcpy(rpdev->id.name, "rpmsg_ctrl"); - rpdev->driver_override = "rpmsg_ctrl"; + int ret; - return rpmsg_register_device(rpdev); + strcpy(rpdev->id.name, "rpmsg_ctrl"); + ret = driver_set_override(&rpdev->dev, &rpdev->driver_override, + rpdev->id.name, strlen(rpdev->id.name)); + if (ret) + return ret; + + ret = rpmsg_register_device(rpdev); + if (ret) + kfree(rpdev->driver_override); + + return ret; } #endif diff --git a/drivers/rpmsg/rpmsg_ns.c b/drivers/rpmsg/rpmsg_ns.c index 762ff1ae279f..8eb8f328237e 100644 --- a/drivers/rpmsg/rpmsg_ns.c +++ b/drivers/rpmsg/rpmsg_ns.c @@ -20,12 +20,22 @@ */ int rpmsg_ns_register_device(struct rpmsg_device *rpdev) { + int ret; + strcpy(rpdev->id.name, "rpmsg_ns"); - rpdev->driver_override = "rpmsg_ns"; + ret = driver_set_override(&rpdev->dev, &rpdev->driver_override, + rpdev->id.name, strlen(rpdev->id.name)); + if (ret) + return ret; + rpdev->src = RPMSG_NS_ADDR; rpdev->dst = RPMSG_NS_ADDR; - return rpmsg_register_device(rpdev); + ret = rpmsg_register_device(rpdev); + if (ret) + kfree(rpdev->driver_override); + + return ret; } EXPORT_SYMBOL(rpmsg_ns_register_device); diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h index 02fa9116cd60..20c8cd1cde21 100644 --- a/include/linux/rpmsg.h +++ b/include/linux/rpmsg.h @@ -41,7 +41,9 @@ struct rpmsg_channel_info { * rpmsg_device - device that belong to the rpmsg bus * @dev: the device struct * @id: device id (used to match between rpmsg drivers and devices) - * @driver_override: driver name to force a match + * @driver_override: driver name to force a match; do not set directly, + * because core frees it; use driver_set_override() to + * set or clear it. * @src: local address * @dst: destination address * @ept: the rpmsg endpoint of this channel @@ -51,7 +53,7 @@ struct rpmsg_channel_info { struct rpmsg_device { struct device dev; struct rpmsg_device_id id; - char *driver_override; + const char *driver_override; u32 src; u32 dst; struct rpmsg_endpoint *ept;