| Message ID | 20220227135329.145862-5-krzysztof.kozlowski@canonical.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Fix broken usage of driver_override (and kfree of static memory) | expand |
On Sun 27 Feb 07:53 CST 2022, Krzysztof Kozlowski wrote: > 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") > Cc: <stable@vger.kernel.org> > Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> Regards, Bjorn > --- > drivers/rpmsg/rpmsg_core.c | 3 ++- > drivers/rpmsg/rpmsg_internal.h | 13 +++++++++++-- > drivers/rpmsg/rpmsg_ns.c | 14 ++++++++++++-- > include/linux/rpmsg.h | 6 ++++-- > 4 files changed, 29 insertions(+), 7 deletions(-) > > diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c > index d9e612f4f0f2..6e2bf2742973 100644 > --- a/drivers/rpmsg/rpmsg_core.c > +++ b/drivers/rpmsg/rpmsg_core.c > @@ -397,7 +397,8 @@ 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) \ > diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h > index b1245d3ed7c6..31345d6e9a7e 100644 > --- a/drivers/rpmsg/rpmsg_internal.h > +++ b/drivers/rpmsg/rpmsg_internal.h > @@ -92,10 +92,19 @@ int rpmsg_release_channel(struct rpmsg_device *rpdev, > */ > static inline int rpmsg_chrdev_register_device(struct rpmsg_device *rpdev) > { > + int ret; > + > strcpy(rpdev->id.name, "rpmsg_chrdev"); > - rpdev->driver_override = "rpmsg_chrdev"; > + ret = driver_set_override(&rpdev->dev, &rpdev->driver_override, > + "rpmsg_chrdev", strlen("rpmsg_chrdev")); > + 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..95a51543f5ad 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, > + "rpmsg_ns", strlen("rpmsg_ns")); > + 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; > -- > 2.32.0 >
diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c index d9e612f4f0f2..6e2bf2742973 100644 --- a/drivers/rpmsg/rpmsg_core.c +++ b/drivers/rpmsg/rpmsg_core.c @@ -397,7 +397,8 @@ 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) \ diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h index b1245d3ed7c6..31345d6e9a7e 100644 --- a/drivers/rpmsg/rpmsg_internal.h +++ b/drivers/rpmsg/rpmsg_internal.h @@ -92,10 +92,19 @@ int rpmsg_release_channel(struct rpmsg_device *rpdev, */ static inline int rpmsg_chrdev_register_device(struct rpmsg_device *rpdev) { + int ret; + strcpy(rpdev->id.name, "rpmsg_chrdev"); - rpdev->driver_override = "rpmsg_chrdev"; + ret = driver_set_override(&rpdev->dev, &rpdev->driver_override, + "rpmsg_chrdev", strlen("rpmsg_chrdev")); + 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..95a51543f5ad 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, + "rpmsg_ns", strlen("rpmsg_ns")); + 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;
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") Cc: <stable@vger.kernel.org> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> --- drivers/rpmsg/rpmsg_core.c | 3 ++- drivers/rpmsg/rpmsg_internal.h | 13 +++++++++++-- drivers/rpmsg/rpmsg_ns.c | 14 ++++++++++++-- include/linux/rpmsg.h | 6 ++++-- 4 files changed, 29 insertions(+), 7 deletions(-)