From e5f89131a06142e91073b6959d91cea73861d40e Mon Sep 17 00:00:00 2001 From: Krzysztof Kozlowski Date: Tue, 19 Apr 2022 13:34:34 +0200 Subject: rpmsg: Constify local variable in field store macro Memory pointed by variable 'old' in field store macro is not modified, so it can be made a pointer to const. Signed-off-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20220419113435.246203-12-krzysztof.kozlowski@linaro.org Signed-off-by: Greg Kroah-Hartman --- drivers/rpmsg/rpmsg_core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/rpmsg') diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c index 79368a957d89..95fc283f6af7 100644 --- a/drivers/rpmsg/rpmsg_core.c +++ b/drivers/rpmsg/rpmsg_core.c @@ -400,7 +400,8 @@ field##_store(struct device *dev, struct device_attribute *attr, \ const char *buf, size_t sz) \ { \ struct rpmsg_device *rpdev = to_rpmsg_device(dev); \ - char *new, *old; \ + const char *old; \ + char *new; \ \ new = kstrndup(buf, sz, GFP_KERNEL); \ if (!new) \ -- cgit v1.2.3 From 42cd402b8fd4672b692400fe5f9eecd55d2794ac Mon Sep 17 00:00:00 2001 From: Krzysztof Kozlowski Date: Tue, 19 Apr 2022 13:34:35 +0200 Subject: 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 | 13 +++++++++++-- drivers/rpmsg/rpmsg_ns.c | 14 ++++++++++++-- include/linux/rpmsg.h | 6 ++++-- 3 files changed, 27 insertions(+), 6 deletions(-) (limited to 'drivers/rpmsg') 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) { + int ret; + strcpy(rpdev->id.name, "rpmsg_ctrl"); - rpdev->driver_override = "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 rpmsg_register_device(rpdev); + 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; -- cgit v1.2.3 From bb17d110cbf270d5247a6e261c5ad50e362d1675 Mon Sep 17 00:00:00 2001 From: Krzysztof Kozlowski Date: Fri, 29 Apr 2022 21:59:45 +0200 Subject: rpmsg: Fix calling device_lock() on non-initialized device driver_set_override() helper uses device_lock() so it should not be called before rpmsg_register_device() (which calls device_register()). Effect can be seen with CONFIG_DEBUG_MUTEXES: DEBUG_LOCKS_WARN_ON(lock->magic != lock) WARNING: CPU: 3 PID: 57 at kernel/locking/mutex.c:582 __mutex_lock+0x1ec/0x430 ... Call trace: __mutex_lock+0x1ec/0x430 mutex_lock_nested+0x44/0x50 driver_set_override+0x124/0x150 qcom_glink_native_probe+0x30c/0x3b0 glink_rpm_probe+0x274/0x350 platform_probe+0x6c/0xe0 really_probe+0x17c/0x3d0 __driver_probe_device+0x114/0x190 driver_probe_device+0x3c/0xf0 ... Refactor the rpmsg_register_device() function to use two-step device registering (initialization + add) and call driver_set_override() in proper moment. This moves the code around, so while at it also NULL-ify the rpdev->driver_override in error path to be sure it won't be kfree() second time. Fixes: 42cd402b8fd4 ("rpmsg: Fix kfree() of static memory on setting driver_override") Reported-by: Marek Szyprowski Signed-off-by: Krzysztof Kozlowski Tested-by: Marek Szyprowski Link: https://lore.kernel.org/r/20220429195946.1061725-2-krzysztof.kozlowski@linaro.org Signed-off-by: Greg Kroah-Hartman --- drivers/rpmsg/rpmsg_core.c | 33 ++++++++++++++++++++++++++++++--- drivers/rpmsg/rpmsg_internal.h | 14 +------------- drivers/rpmsg/rpmsg_ns.c | 14 +------------- include/linux/rpmsg.h | 8 ++++++++ 4 files changed, 40 insertions(+), 29 deletions(-) (limited to 'drivers/rpmsg') diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c index 95fc283f6af7..4938fc4eff00 100644 --- a/drivers/rpmsg/rpmsg_core.c +++ b/drivers/rpmsg/rpmsg_core.c @@ -593,24 +593,51 @@ static struct bus_type rpmsg_bus = { .remove = rpmsg_dev_remove, }; -int rpmsg_register_device(struct rpmsg_device *rpdev) +/* + * A helper for registering rpmsg device with driver override and name. + * Drivers should not be using it, but instead rpmsg_register_device(). + */ +int rpmsg_register_device_override(struct rpmsg_device *rpdev, + const char *driver_override) { struct device *dev = &rpdev->dev; int ret; + if (driver_override) + strcpy(rpdev->id.name, driver_override); + dev_set_name(&rpdev->dev, "%s.%s.%d.%d", dev_name(dev->parent), rpdev->id.name, rpdev->src, rpdev->dst); rpdev->dev.bus = &rpmsg_bus; - ret = device_register(&rpdev->dev); + device_initialize(dev); + if (driver_override) { + ret = driver_set_override(dev, &rpdev->driver_override, + driver_override, + strlen(driver_override)); + if (ret) { + dev_err(dev, "device_set_override failed: %d\n", ret); + return ret; + } + } + + ret = device_add(dev); if (ret) { - dev_err(dev, "device_register failed: %d\n", ret); + dev_err(dev, "device_add failed: %d\n", ret); + kfree(rpdev->driver_override); + rpdev->driver_override = NULL; put_device(&rpdev->dev); } return ret; } +EXPORT_SYMBOL(rpmsg_register_device_override); + +int rpmsg_register_device(struct rpmsg_device *rpdev) +{ + return rpmsg_register_device_override(rpdev, NULL); +} EXPORT_SYMBOL(rpmsg_register_device); /* diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h index 3e81642238d2..a22cd4abe7d1 100644 --- a/drivers/rpmsg/rpmsg_internal.h +++ b/drivers/rpmsg/rpmsg_internal.h @@ -94,19 +94,7 @@ int rpmsg_release_channel(struct rpmsg_device *rpdev, */ static inline int rpmsg_ctrldev_register_device(struct rpmsg_device *rpdev) { - int ret; - - 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; + return rpmsg_register_device_override(rpdev, "rpmsg_ctrl"); } #endif diff --git a/drivers/rpmsg/rpmsg_ns.c b/drivers/rpmsg/rpmsg_ns.c index 8eb8f328237e..c70ad03ff2e9 100644 --- a/drivers/rpmsg/rpmsg_ns.c +++ b/drivers/rpmsg/rpmsg_ns.c @@ -20,22 +20,10 @@ */ int rpmsg_ns_register_device(struct rpmsg_device *rpdev) { - int ret; - - strcpy(rpdev->id.name, "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; - ret = rpmsg_register_device(rpdev); - if (ret) - kfree(rpdev->driver_override); - - return ret; + return rpmsg_register_device_override(rpdev, "rpmsg_ns"); } EXPORT_SYMBOL(rpmsg_ns_register_device); diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h index 20c8cd1cde21..523c98b96cb4 100644 --- a/include/linux/rpmsg.h +++ b/include/linux/rpmsg.h @@ -165,6 +165,8 @@ static inline __rpmsg64 cpu_to_rpmsg64(struct rpmsg_device *rpdev, u64 val) #if IS_ENABLED(CONFIG_RPMSG) +int rpmsg_register_device_override(struct rpmsg_device *rpdev, + const char *driver_override); int rpmsg_register_device(struct rpmsg_device *rpdev); int rpmsg_unregister_device(struct device *parent, struct rpmsg_channel_info *chinfo); @@ -192,6 +194,12 @@ ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept); #else +static inline int rpmsg_register_device_override(struct rpmsg_device *rpdev, + const char *driver_override) +{ + return -ENXIO; +} + static inline int rpmsg_register_device(struct rpmsg_device *rpdev) { return -ENXIO; -- cgit v1.2.3 From 38ea74eb8fc1b82b39e13a6527095a0036539117 Mon Sep 17 00:00:00 2001 From: Krzysztof Kozlowski Date: Fri, 29 Apr 2022 21:59:46 +0200 Subject: rpmsg: use local 'dev' variable '&rpdev->dev' is already cached as local variable, so use it to simplify the code. Signed-off-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20220429195946.1061725-3-krzysztof.kozlowski@linaro.org Signed-off-by: Greg Kroah-Hartman --- drivers/rpmsg/rpmsg_core.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers/rpmsg') diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c index 4938fc4eff00..290c1f02da10 100644 --- a/drivers/rpmsg/rpmsg_core.c +++ b/drivers/rpmsg/rpmsg_core.c @@ -606,10 +606,10 @@ int rpmsg_register_device_override(struct rpmsg_device *rpdev, if (driver_override) strcpy(rpdev->id.name, driver_override); - dev_set_name(&rpdev->dev, "%s.%s.%d.%d", dev_name(dev->parent), + dev_set_name(dev, "%s.%s.%d.%d", dev_name(dev->parent), rpdev->id.name, rpdev->src, rpdev->dst); - rpdev->dev.bus = &rpmsg_bus; + dev->bus = &rpmsg_bus; device_initialize(dev); if (driver_override) { @@ -627,7 +627,7 @@ int rpmsg_register_device_override(struct rpmsg_device *rpdev, dev_err(dev, "device_add failed: %d\n", ret); kfree(rpdev->driver_override); rpdev->driver_override = NULL; - put_device(&rpdev->dev); + put_device(dev); } return ret; -- cgit v1.2.3