[PATCH 6.1 0/2] Backport to fix CVE-2024-37021 and CVE-2024-36479

[PATCH 6.1 0/2] Backport to fix CVE-2024-37021 and CVE-2024-36479

[Xiangyu Chen]

From: Xiangyu Chen <xiangyu.chen@windriver.com>

The fix of CVE-2024-36479:
fpga: bridge: add owner module and take its refcount
master rev 1da11f822042eb6ef4b6064dc048f157a7852529

The fix of CVE-2024-37021:
fpga: manager: add owner module and take its refcount
master rev 4d4d2d4346857bf778fafaa97d6f76bb1663e3c9


Marco Pagani (2):
  fpga: bridge: add owner module and take its refcount
  fpga: manager: add owner module and take its refcount

 Documentation/driver-api/fpga/fpga-bridge.rst |  7 +-
 Documentation/driver-api/fpga/fpga-mgr.rst    | 34 ++++----
 drivers/fpga/fpga-bridge.c                    | 57 +++++++------
 drivers/fpga/fpga-mgr.c                       | 82 +++++++++++--------
 include/linux/fpga/fpga-bridge.h              | 10 ++-
 include/linux/fpga/fpga-mgr.h                 | 26 ++++--
 6 files changed, 132 insertions(+), 84 deletions(-)

-- 
2.43.0

[PATCH 6.1 1/2] fpga: bridge: add owner module and take its refcount

[Xiangyu Chen]

From: Marco Pagani <marpagan@redhat.com>

[ Upstream commit 1da11f822042eb6ef4b6064dc048f157a7852529 ]

The current implementation of the fpga bridge assumes that the low-level
module registers a driver for the parent device and uses its owner pointer
to take the module's refcount. This approach is problematic since it can
lead to a null pointer dereference while attempting to get the bridge if
the parent device does not have a driver.

To address this problem, add a module owner pointer to the fpga_bridge
struct and use it to take the module's refcount. Modify the function for
registering a bridge to take an additional owner module parameter and
rename it to avoid conflicts. Use the old function name for a helper macro
that automatically sets the module that registers the bridge as the owner.
This ensures compatibility with existing low-level control modules and
reduces the chances of registering a bridge without setting the owner.

Also, update the documentation to keep it consistent with the new interface
for registering an fpga bridge.

Other changes: opportunistically move put_device() from __fpga_bridge_get()
to fpga_bridge_get() and of_fpga_bridge_get() to improve code clarity since
the bridge device is taken in these functions.

Fixes: 21aeda950c5f ("fpga: add fpga bridge framework")
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: Xu Yilun <yilun.xu@intel.com>
Reviewed-by: Russ Weight <russ.weight@linux.dev>
Signed-off-by: Marco Pagani <marpagan@redhat.com>
Acked-by: Xu Yilun <yilun.xu@intel.com>
Link: https://lore.kernel.org/r/20240322171839.233864-1-marpagan@redhat.com
Signed-off-by: Xu Yilun <yilun.xu@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Xiangyu Chen <xiangyu.chen@windriver.com>
---
 Documentation/driver-api/fpga/fpga-bridge.rst |  7 ++-
 drivers/fpga/fpga-bridge.c                    | 57 ++++++++++---------
 include/linux/fpga/fpga-bridge.h              | 10 +++-
 3 files changed, 43 insertions(+), 31 deletions(-)

diff --git a/Documentation/driver-api/fpga/fpga-bridge.rst b/Documentation/driver-api/fpga/fpga-bridge.rst
index 604208534095..833f68fb0700 100644
--- a/Documentation/driver-api/fpga/fpga-bridge.rst
+++ b/Documentation/driver-api/fpga/fpga-bridge.rst
@@ -6,9 +6,12 @@ API to implement a new FPGA bridge
 
 * struct fpga_bridge - The FPGA Bridge structure
 * struct fpga_bridge_ops - Low level Bridge driver ops
-* fpga_bridge_register() - Create and register a bridge
+* __fpga_bridge_register() - Create and register a bridge
 * fpga_bridge_unregister() - Unregister a bridge
 
+The helper macro ``fpga_bridge_register()`` automatically sets
+the module that registers the FPGA bridge as the owner.
+
 .. kernel-doc:: include/linux/fpga/fpga-bridge.h
    :functions: fpga_bridge
 
@@ -16,7 +19,7 @@ API to implement a new FPGA bridge
    :functions: fpga_bridge_ops
 
 .. kernel-doc:: drivers/fpga/fpga-bridge.c
-   :functions: fpga_bridge_register
+   :functions: __fpga_bridge_register
 
 .. kernel-doc:: drivers/fpga/fpga-bridge.c
    :functions: fpga_bridge_unregister
diff --git a/drivers/fpga/fpga-bridge.c b/drivers/fpga/fpga-bridge.c
index 833ce13ff6f8..698d6cbf782a 100644
--- a/drivers/fpga/fpga-bridge.c
+++ b/drivers/fpga/fpga-bridge.c
@@ -55,33 +55,26 @@ int fpga_bridge_disable(struct fpga_bridge *bridge)
 }
 EXPORT_SYMBOL_GPL(fpga_bridge_disable);
 
-static struct fpga_bridge *__fpga_bridge_get(struct device *dev,
+static struct fpga_bridge *__fpga_bridge_get(struct device *bridge_dev,
 					     struct fpga_image_info *info)
 {
 	struct fpga_bridge *bridge;
-	int ret = -ENODEV;
 
-	bridge = to_fpga_bridge(dev);
+	bridge = to_fpga_bridge(bridge_dev);
 
 	bridge->info = info;
 
-	if (!mutex_trylock(&bridge->mutex)) {
-		ret = -EBUSY;
-		goto err_dev;
-	}
+	if (!mutex_trylock(&bridge->mutex))
+		return ERR_PTR(-EBUSY);
 
-	if (!try_module_get(dev->parent->driver->owner))
-		goto err_ll_mod;
+	if (!try_module_get(bridge->br_ops_owner)) {
+		mutex_unlock(&bridge->mutex);
+		return ERR_PTR(-ENODEV);
+	}
 
 	dev_dbg(&bridge->dev, "get\n");
 
 	return bridge;
-
-err_ll_mod:
-	mutex_unlock(&bridge->mutex);
-err_dev:
-	put_device(dev);
-	return ERR_PTR(ret);
 }
 
 /**
@@ -97,13 +90,18 @@ static struct fpga_bridge *__fpga_bridge_get(struct device *dev,
 struct fpga_bridge *of_fpga_bridge_get(struct device_node *np,
 				       struct fpga_image_info *info)
 {
-	struct device *dev;
+	struct fpga_bridge *bridge;
+	struct device *bridge_dev;
 
-	dev = class_find_device_by_of_node(fpga_bridge_class, np);
-	if (!dev)
+	bridge_dev = class_find_device_by_of_node(fpga_bridge_class, np);
+	if (!bridge_dev)
 		return ERR_PTR(-ENODEV);
 
-	return __fpga_bridge_get(dev, info);
+	bridge = __fpga_bridge_get(bridge_dev, info);
+	if (IS_ERR(bridge))
+		put_device(bridge_dev);
+
+	return bridge;
 }
 EXPORT_SYMBOL_GPL(of_fpga_bridge_get);
 
@@ -124,6 +122,7 @@ static int fpga_bridge_dev_match(struct device *dev, const void *data)
 struct fpga_bridge *fpga_bridge_get(struct device *dev,
 				    struct fpga_image_info *info)
 {
+	struct fpga_bridge *bridge;
 	struct device *bridge_dev;
 
 	bridge_dev = class_find_device(fpga_bridge_class, NULL, dev,
@@ -131,7 +130,11 @@ struct fpga_bridge *fpga_bridge_get(struct device *dev,
 	if (!bridge_dev)
 		return ERR_PTR(-ENODEV);
 
-	return __fpga_bridge_get(bridge_dev, info);
+	bridge = __fpga_bridge_get(bridge_dev, info);
+	if (IS_ERR(bridge))
+		put_device(bridge_dev);
+
+	return bridge;
 }
 EXPORT_SYMBOL_GPL(fpga_bridge_get);
 
@@ -145,7 +148,7 @@ void fpga_bridge_put(struct fpga_bridge *bridge)
 	dev_dbg(&bridge->dev, "put\n");
 
 	bridge->info = NULL;
-	module_put(bridge->dev.parent->driver->owner);
+	module_put(bridge->br_ops_owner);
 	mutex_unlock(&bridge->mutex);
 	put_device(&bridge->dev);
 }
@@ -312,18 +315,19 @@ static struct attribute *fpga_bridge_attrs[] = {
 ATTRIBUTE_GROUPS(fpga_bridge);
 
 /**
- * fpga_bridge_register - create and register an FPGA Bridge device
+ * __fpga_bridge_register - create and register an FPGA Bridge device
  * @parent:	FPGA bridge device from pdev
  * @name:	FPGA bridge name
  * @br_ops:	pointer to structure of fpga bridge ops
  * @priv:	FPGA bridge private data
+ * @owner:	owner module containing the br_ops
  *
  * Return: struct fpga_bridge pointer or ERR_PTR()
  */
 struct fpga_bridge *
-fpga_bridge_register(struct device *parent, const char *name,
-		     const struct fpga_bridge_ops *br_ops,
-		     void *priv)
+__fpga_bridge_register(struct device *parent, const char *name,
+		       const struct fpga_bridge_ops *br_ops,
+		       void *priv, struct module *owner)
 {
 	struct fpga_bridge *bridge;
 	int id, ret;
@@ -353,6 +357,7 @@ fpga_bridge_register(struct device *parent, const char *name,
 
 	bridge->name = name;
 	bridge->br_ops = br_ops;
+	bridge->br_ops_owner = owner;
 	bridge->priv = priv;
 
 	bridge->dev.groups = br_ops->groups;
@@ -382,7 +387,7 @@ fpga_bridge_register(struct device *parent, const char *name,
 
 	return ERR_PTR(ret);
 }
-EXPORT_SYMBOL_GPL(fpga_bridge_register);
+EXPORT_SYMBOL_GPL(__fpga_bridge_register);
 
 /**
  * fpga_bridge_unregister - unregister an FPGA bridge
diff --git a/include/linux/fpga/fpga-bridge.h b/include/linux/fpga/fpga-bridge.h
index 223da48a6d18..94c4edd047e5 100644
--- a/include/linux/fpga/fpga-bridge.h
+++ b/include/linux/fpga/fpga-bridge.h
@@ -45,6 +45,7 @@ struct fpga_bridge_info {
  * @dev: FPGA bridge device
  * @mutex: enforces exclusive reference to bridge
  * @br_ops: pointer to struct of FPGA bridge ops
+ * @br_ops_owner: module containing the br_ops
  * @info: fpga image specific information
  * @node: FPGA bridge list node
  * @priv: low level driver private date
@@ -54,6 +55,7 @@ struct fpga_bridge {
 	struct device dev;
 	struct mutex mutex; /* for exclusive reference to bridge */
 	const struct fpga_bridge_ops *br_ops;
+	struct module *br_ops_owner;
 	struct fpga_image_info *info;
 	struct list_head node;
 	void *priv;
@@ -79,10 +81,12 @@ int of_fpga_bridge_get_to_list(struct device_node *np,
 			       struct fpga_image_info *info,
 			       struct list_head *bridge_list);
 
+#define fpga_bridge_register(parent, name, br_ops, priv) \
+	__fpga_bridge_register(parent, name, br_ops, priv, THIS_MODULE)
 struct fpga_bridge *
-fpga_bridge_register(struct device *parent, const char *name,
-		     const struct fpga_bridge_ops *br_ops,
-		     void *priv);
+__fpga_bridge_register(struct device *parent, const char *name,
+		       const struct fpga_bridge_ops *br_ops, void *priv,
+		       struct module *owner);
 void fpga_bridge_unregister(struct fpga_bridge *br);
 
 #endif /* _LINUX_FPGA_BRIDGE_H */
-- 
2.43.0

[PATCH 6.1 2/2] fpga: manager: add owner module and take its refcount

[Xiangyu Chen]

From: Marco Pagani <marpagan@redhat.com>

[ Upstream commit 4d4d2d4346857bf778fafaa97d6f76bb1663e3c9 ]

The current implementation of the fpga manager assumes that the low-level
module registers a driver for the parent device and uses its owner pointer
to take the module's refcount. This approach is problematic since it can
lead to a null pointer dereference while attempting to get the manager if
the parent device does not have a driver.

To address this problem, add a module owner pointer to the fpga_manager
struct and use it to take the module's refcount. Modify the functions for
registering the manager to take an additional owner module parameter and
rename them to avoid conflicts. Use the old function names for helper
macros that automatically set the module that registers the manager as the
owner. This ensures compatibility with existing low-level control modules
and reduces the chances of registering a manager without setting the owner.

Also, update the documentation to keep it consistent with the new interface
for registering an fpga manager.

Other changes: opportunistically move put_device() from __fpga_mgr_get() to
fpga_mgr_get() and of_fpga_mgr_get() to improve code clarity since the
manager device is taken in these functions.

Fixes: 654ba4cc0f3e ("fpga manager: ensure lifetime with of_fpga_mgr_get")
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: Xu Yilun <yilun.xu@intel.com>
Signed-off-by: Marco Pagani <marpagan@redhat.com>
Acked-by: Xu Yilun <yilun.xu@intel.com>
Link: https://lore.kernel.org/r/20240305192926.84886-1-marpagan@redhat.com
Signed-off-by: Xu Yilun <yilun.xu@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Xiangyu Chen <xiangyu.chen@windriver.com>
---
 Documentation/driver-api/fpga/fpga-mgr.rst | 34 +++++----
 drivers/fpga/fpga-mgr.c                    | 82 +++++++++++++---------
 include/linux/fpga/fpga-mgr.h              | 26 +++++--
 3 files changed, 89 insertions(+), 53 deletions(-)

diff --git a/Documentation/driver-api/fpga/fpga-mgr.rst b/Documentation/driver-api/fpga/fpga-mgr.rst
index 49c0a9512653..8d2b79f696c1 100644
--- a/Documentation/driver-api/fpga/fpga-mgr.rst
+++ b/Documentation/driver-api/fpga/fpga-mgr.rst
@@ -24,7 +24,8 @@ How to support a new FPGA device
 --------------------------------
 
 To add another FPGA manager, write a driver that implements a set of ops.  The
-probe function calls fpga_mgr_register() or fpga_mgr_register_full(), such as::
+probe function calls ``fpga_mgr_register()`` or ``fpga_mgr_register_full()``,
+such as::
 
 	static const struct fpga_manager_ops socfpga_fpga_ops = {
 		.write_init = socfpga_fpga_ops_configure_init,
@@ -69,10 +70,11 @@ probe function calls fpga_mgr_register() or fpga_mgr_register_full(), such as::
 	}
 
 Alternatively, the probe function could call one of the resource managed
-register functions, devm_fpga_mgr_register() or devm_fpga_mgr_register_full().
-When these functions are used, the parameter syntax is the same, but the call
-to fpga_mgr_unregister() should be removed. In the above example, the
-socfpga_fpga_remove() function would not be required.
+register functions, ``devm_fpga_mgr_register()`` or
+``devm_fpga_mgr_register_full()``.  When these functions are used, the
+parameter syntax is the same, but the call to ``fpga_mgr_unregister()`` should be
+removed. In the above example, the ``socfpga_fpga_remove()`` function would not be
+required.
 
 The ops will implement whatever device specific register writes are needed to
 do the programming sequence for this particular FPGA.  These ops return 0 for
@@ -125,15 +127,19 @@ API for implementing a new FPGA Manager driver
 * struct fpga_manager -  the FPGA manager struct
 * struct fpga_manager_ops -  Low level FPGA manager driver ops
 * struct fpga_manager_info -  Parameter structure for fpga_mgr_register_full()
-* fpga_mgr_register_full() -  Create and register an FPGA manager using the
+* __fpga_mgr_register_full() -  Create and register an FPGA manager using the
   fpga_mgr_info structure to provide the full flexibility of options
-* fpga_mgr_register() -  Create and register an FPGA manager using standard
+* __fpga_mgr_register() -  Create and register an FPGA manager using standard
   arguments
-* devm_fpga_mgr_register_full() -  Resource managed version of
-  fpga_mgr_register_full()
-* devm_fpga_mgr_register() -  Resource managed version of fpga_mgr_register()
+* __devm_fpga_mgr_register_full() -  Resource managed version of
+  __fpga_mgr_register_full()
+* __devm_fpga_mgr_register() -  Resource managed version of __fpga_mgr_register()
 * fpga_mgr_unregister() -  Unregister an FPGA manager
 
+Helper macros ``fpga_mgr_register_full()``, ``fpga_mgr_register()``,
+``devm_fpga_mgr_register_full()``, and ``devm_fpga_mgr_register()`` are available
+to ease the registration.
+
 .. kernel-doc:: include/linux/fpga/fpga-mgr.h
    :functions: fpga_mgr_states
 
@@ -147,16 +153,16 @@ API for implementing a new FPGA Manager driver
    :functions: fpga_manager_info
 
 .. kernel-doc:: drivers/fpga/fpga-mgr.c
-   :functions: fpga_mgr_register_full
+   :functions: __fpga_mgr_register_full
 
 .. kernel-doc:: drivers/fpga/fpga-mgr.c
-   :functions: fpga_mgr_register
+   :functions: __fpga_mgr_register
 
 .. kernel-doc:: drivers/fpga/fpga-mgr.c
-   :functions: devm_fpga_mgr_register_full
+   :functions: __devm_fpga_mgr_register_full
 
 .. kernel-doc:: drivers/fpga/fpga-mgr.c
-   :functions: devm_fpga_mgr_register
+   :functions: __devm_fpga_mgr_register
 
 .. kernel-doc:: drivers/fpga/fpga-mgr.c
    :functions: fpga_mgr_unregister
diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
index 8efa67620e21..0c71d91ba7f6 100644
--- a/drivers/fpga/fpga-mgr.c
+++ b/drivers/fpga/fpga-mgr.c
@@ -664,20 +664,16 @@ static struct attribute *fpga_mgr_attrs[] = {
 };
 ATTRIBUTE_GROUPS(fpga_mgr);
 
-static struct fpga_manager *__fpga_mgr_get(struct device *dev)
+static struct fpga_manager *__fpga_mgr_get(struct device *mgr_dev)
 {
 	struct fpga_manager *mgr;
 
-	mgr = to_fpga_manager(dev);
+	mgr = to_fpga_manager(mgr_dev);
 
-	if (!try_module_get(dev->parent->driver->owner))
-		goto err_dev;
+	if (!try_module_get(mgr->mops_owner))
+		mgr = ERR_PTR(-ENODEV);
 
 	return mgr;
-
-err_dev:
-	put_device(dev);
-	return ERR_PTR(-ENODEV);
 }
 
 static int fpga_mgr_dev_match(struct device *dev, const void *data)
@@ -693,12 +689,18 @@ static int fpga_mgr_dev_match(struct device *dev, const void *data)
  */
 struct fpga_manager *fpga_mgr_get(struct device *dev)
 {
-	struct device *mgr_dev = class_find_device(fpga_mgr_class, NULL, dev,
-						   fpga_mgr_dev_match);
+	struct fpga_manager *mgr;
+	struct device *mgr_dev;
+
+	mgr_dev = class_find_device(fpga_mgr_class, NULL, dev, fpga_mgr_dev_match);
 	if (!mgr_dev)
 		return ERR_PTR(-ENODEV);
 
-	return __fpga_mgr_get(mgr_dev);
+	mgr = __fpga_mgr_get(mgr_dev);
+	if (IS_ERR(mgr))
+		put_device(mgr_dev);
+
+	return mgr;
 }
 EXPORT_SYMBOL_GPL(fpga_mgr_get);
 
@@ -711,13 +713,18 @@ EXPORT_SYMBOL_GPL(fpga_mgr_get);
  */
 struct fpga_manager *of_fpga_mgr_get(struct device_node *node)
 {
-	struct device *dev;
+	struct fpga_manager *mgr;
+	struct device *mgr_dev;
 
-	dev = class_find_device_by_of_node(fpga_mgr_class, node);
-	if (!dev)
+	mgr_dev = class_find_device_by_of_node(fpga_mgr_class, node);
+	if (!mgr_dev)
 		return ERR_PTR(-ENODEV);
 
-	return __fpga_mgr_get(dev);
+	mgr = __fpga_mgr_get(mgr_dev);
+	if (IS_ERR(mgr))
+		put_device(mgr_dev);
+
+	return mgr;
 }
 EXPORT_SYMBOL_GPL(of_fpga_mgr_get);
 
@@ -727,7 +734,7 @@ EXPORT_SYMBOL_GPL(of_fpga_mgr_get);
  */
 void fpga_mgr_put(struct fpga_manager *mgr)
 {
-	module_put(mgr->dev.parent->driver->owner);
+	module_put(mgr->mops_owner);
 	put_device(&mgr->dev);
 }
 EXPORT_SYMBOL_GPL(fpga_mgr_put);
@@ -766,9 +773,10 @@ void fpga_mgr_unlock(struct fpga_manager *mgr)
 EXPORT_SYMBOL_GPL(fpga_mgr_unlock);
 
 /**
- * fpga_mgr_register_full - create and register an FPGA Manager device
+ * __fpga_mgr_register_full - create and register an FPGA Manager device
  * @parent:	fpga manager device from pdev
  * @info:	parameters for fpga manager
+ * @owner:	owner module containing the ops
  *
  * The caller of this function is responsible for calling fpga_mgr_unregister().
  * Using devm_fpga_mgr_register_full() instead is recommended.
@@ -776,7 +784,8 @@ EXPORT_SYMBOL_GPL(fpga_mgr_unlock);
  * Return: pointer to struct fpga_manager pointer or ERR_PTR()
  */
 struct fpga_manager *
-fpga_mgr_register_full(struct device *parent, const struct fpga_manager_info *info)
+__fpga_mgr_register_full(struct device *parent, const struct fpga_manager_info *info,
+			 struct module *owner)
 {
 	const struct fpga_manager_ops *mops = info->mops;
 	struct fpga_manager *mgr;
@@ -804,6 +813,8 @@ fpga_mgr_register_full(struct device *parent, const struct fpga_manager_info *in
 
 	mutex_init(&mgr->ref_mutex);
 
+	mgr->mops_owner = owner;
+
 	mgr->name = info->name;
 	mgr->mops = info->mops;
 	mgr->priv = info->priv;
@@ -841,14 +852,15 @@ fpga_mgr_register_full(struct device *parent, const struct fpga_manager_info *in
 
 	return ERR_PTR(ret);
 }
-EXPORT_SYMBOL_GPL(fpga_mgr_register_full);
+EXPORT_SYMBOL_GPL(__fpga_mgr_register_full);
 
 /**
- * fpga_mgr_register - create and register an FPGA Manager device
+ * __fpga_mgr_register - create and register an FPGA Manager device
  * @parent:	fpga manager device from pdev
  * @name:	fpga manager name
  * @mops:	pointer to structure of fpga manager ops
  * @priv:	fpga manager private data
+ * @owner:	owner module containing the ops
  *
  * The caller of this function is responsible for calling fpga_mgr_unregister().
  * Using devm_fpga_mgr_register() instead is recommended. This simple
@@ -859,8 +871,8 @@ EXPORT_SYMBOL_GPL(fpga_mgr_register_full);
  * Return: pointer to struct fpga_manager pointer or ERR_PTR()
  */
 struct fpga_manager *
-fpga_mgr_register(struct device *parent, const char *name,
-		  const struct fpga_manager_ops *mops, void *priv)
+__fpga_mgr_register(struct device *parent, const char *name,
+		    const struct fpga_manager_ops *mops, void *priv, struct module *owner)
 {
 	struct fpga_manager_info info = { 0 };
 
@@ -868,9 +880,9 @@ fpga_mgr_register(struct device *parent, const char *name,
 	info.mops = mops;
 	info.priv = priv;
 
-	return fpga_mgr_register_full(parent, &info);
+	return __fpga_mgr_register_full(parent, &info, owner);
 }
-EXPORT_SYMBOL_GPL(fpga_mgr_register);
+EXPORT_SYMBOL_GPL(__fpga_mgr_register);
 
 /**
  * fpga_mgr_unregister - unregister an FPGA manager
@@ -900,9 +912,10 @@ static void devm_fpga_mgr_unregister(struct device *dev, void *res)
 }
 
 /**
- * devm_fpga_mgr_register_full - resource managed variant of fpga_mgr_register()
+ * __devm_fpga_mgr_register_full - resource managed variant of fpga_mgr_register()
  * @parent:	fpga manager device from pdev
  * @info:	parameters for fpga manager
+ * @owner:	owner module containing the ops
  *
  * Return:  fpga manager pointer on success, negative error code otherwise.
  *
@@ -910,7 +923,8 @@ static void devm_fpga_mgr_unregister(struct device *dev, void *res)
  * function will be called automatically when the managing device is detached.
  */
 struct fpga_manager *
-devm_fpga_mgr_register_full(struct device *parent, const struct fpga_manager_info *info)
+__devm_fpga_mgr_register_full(struct device *parent, const struct fpga_manager_info *info,
+			      struct module *owner)
 {
 	struct fpga_mgr_devres *dr;
 	struct fpga_manager *mgr;
@@ -919,7 +933,7 @@ devm_fpga_mgr_register_full(struct device *parent, const struct fpga_manager_inf
 	if (!dr)
 		return ERR_PTR(-ENOMEM);
 
-	mgr = fpga_mgr_register_full(parent, info);
+	mgr = __fpga_mgr_register_full(parent, info, owner);
 	if (IS_ERR(mgr)) {
 		devres_free(dr);
 		return mgr;
@@ -930,14 +944,15 @@ devm_fpga_mgr_register_full(struct device *parent, const struct fpga_manager_inf
 
 	return mgr;
 }
-EXPORT_SYMBOL_GPL(devm_fpga_mgr_register_full);
+EXPORT_SYMBOL_GPL(__devm_fpga_mgr_register_full);
 
 /**
- * devm_fpga_mgr_register - resource managed variant of fpga_mgr_register()
+ * __devm_fpga_mgr_register - resource managed variant of fpga_mgr_register()
  * @parent:	fpga manager device from pdev
  * @name:	fpga manager name
  * @mops:	pointer to structure of fpga manager ops
  * @priv:	fpga manager private data
+ * @owner:	owner module containing the ops
  *
  * Return:  fpga manager pointer on success, negative error code otherwise.
  *
@@ -946,8 +961,9 @@ EXPORT_SYMBOL_GPL(devm_fpga_mgr_register_full);
  * device is detached.
  */
 struct fpga_manager *
-devm_fpga_mgr_register(struct device *parent, const char *name,
-		       const struct fpga_manager_ops *mops, void *priv)
+__devm_fpga_mgr_register(struct device *parent, const char *name,
+			 const struct fpga_manager_ops *mops, void *priv,
+			 struct module *owner)
 {
 	struct fpga_manager_info info = { 0 };
 
@@ -955,9 +971,9 @@ devm_fpga_mgr_register(struct device *parent, const char *name,
 	info.mops = mops;
 	info.priv = priv;
 
-	return devm_fpga_mgr_register_full(parent, &info);
+	return __devm_fpga_mgr_register_full(parent, &info, owner);
 }
-EXPORT_SYMBOL_GPL(devm_fpga_mgr_register);
+EXPORT_SYMBOL_GPL(__devm_fpga_mgr_register);
 
 static void fpga_mgr_dev_release(struct device *dev)
 {
diff --git a/include/linux/fpga/fpga-mgr.h b/include/linux/fpga/fpga-mgr.h
index 54f63459efd6..0d4fe068f3d8 100644
--- a/include/linux/fpga/fpga-mgr.h
+++ b/include/linux/fpga/fpga-mgr.h
@@ -201,6 +201,7 @@ struct fpga_manager_ops {
  * @state: state of fpga manager
  * @compat_id: FPGA manager id for compatibility check.
  * @mops: pointer to struct of fpga manager ops
+ * @mops_owner: module containing the mops
  * @priv: low level driver private date
  */
 struct fpga_manager {
@@ -210,6 +211,7 @@ struct fpga_manager {
 	enum fpga_mgr_states state;
 	struct fpga_compat_id *compat_id;
 	const struct fpga_manager_ops *mops;
+	struct module *mops_owner;
 	void *priv;
 };
 
@@ -230,18 +232,30 @@ struct fpga_manager *fpga_mgr_get(struct device *dev);
 
 void fpga_mgr_put(struct fpga_manager *mgr);
 
+#define fpga_mgr_register_full(parent, info) \
+	__fpga_mgr_register_full(parent, info, THIS_MODULE)
 struct fpga_manager *
-fpga_mgr_register_full(struct device *parent, const struct fpga_manager_info *info);
+__fpga_mgr_register_full(struct device *parent, const struct fpga_manager_info *info,
+			 struct module *owner);
 
+#define fpga_mgr_register(parent, name, mops, priv) \
+	__fpga_mgr_register(parent, name, mops, priv, THIS_MODULE)
 struct fpga_manager *
-fpga_mgr_register(struct device *parent, const char *name,
-		  const struct fpga_manager_ops *mops, void *priv);
+__fpga_mgr_register(struct device *parent, const char *name,
+		    const struct fpga_manager_ops *mops, void *priv, struct module *owner);
+
 void fpga_mgr_unregister(struct fpga_manager *mgr);
 
+#define devm_fpga_mgr_register_full(parent, info) \
+	__devm_fpga_mgr_register_full(parent, info, THIS_MODULE)
 struct fpga_manager *
-devm_fpga_mgr_register_full(struct device *parent, const struct fpga_manager_info *info);
+__devm_fpga_mgr_register_full(struct device *parent, const struct fpga_manager_info *info,
+			      struct module *owner);
+#define devm_fpga_mgr_register(parent, name, mops, priv) \
+	__devm_fpga_mgr_register(parent, name, mops, priv, THIS_MODULE)
 struct fpga_manager *
-devm_fpga_mgr_register(struct device *parent, const char *name,
-		       const struct fpga_manager_ops *mops, void *priv);
+__devm_fpga_mgr_register(struct device *parent, const char *name,
+			 const struct fpga_manager_ops *mops, void *priv,
+			 struct module *owner);
 
 #endif /*_LINUX_FPGA_MGR_H */
-- 
2.43.0

Re: [PATCH 6.1 2/2] fpga: manager: add owner module and take its refcount

[Sasha Levin]

[ Sasha's backport helper bot ]

Hi,

The upstream commit SHA1 provided is correct: 4d4d2d4346857bf778fafaa97d6f76bb1663e3c9

WARNING: Author mismatch between patch and upstream commit:
Backport author: Xiangyu Chen <xiangyu.chen@eng.windriver.com>
Commit author: Marco Pagani <marpagan@redhat.com>


Status in newer kernel trees:
6.12.y | Present (exact SHA1)
6.11.y | Present (exact SHA1)
6.6.y | Present (different SHA1: 2da62a139a62)
6.1.y | Not found

Note: The patch differs from the upstream commit:
---
--- -	2024-11-25 10:08:25.352634693 -0500
+++ /tmp/tmp.mxHKcERVgS	2024-11-25 10:08:25.345028939 -0500
@@ -1,3 +1,5 @@
+[ Upstream commit 4d4d2d4346857bf778fafaa97d6f76bb1663e3c9 ]
+
 The current implementation of the fpga manager assumes that the low-level
 module registers a driver for the parent device and uses its owner pointer
 to take the module's refcount. This approach is problematic since it can
@@ -26,6 +28,8 @@
 Acked-by: Xu Yilun <yilun.xu@intel.com>
 Link: https://lore.kernel.org/r/20240305192926.84886-1-marpagan@redhat.com
 Signed-off-by: Xu Yilun <yilun.xu@linux.intel.com>
+Signed-off-by: Sasha Levin <sashal@kernel.org>
+Signed-off-by: Xiangyu Chen <xiangyu.chen@windriver.com>
 ---
  Documentation/driver-api/fpga/fpga-mgr.rst | 34 +++++----
  drivers/fpga/fpga-mgr.c                    | 82 +++++++++++++---------
@@ -33,7 +37,7 @@
  3 files changed, 89 insertions(+), 53 deletions(-)
 
 diff --git a/Documentation/driver-api/fpga/fpga-mgr.rst b/Documentation/driver-api/fpga/fpga-mgr.rst
-index 49c0a95126532..8d2b79f696c1f 100644
+index 49c0a9512653..8d2b79f696c1 100644
 --- a/Documentation/driver-api/fpga/fpga-mgr.rst
 +++ b/Documentation/driver-api/fpga/fpga-mgr.rst
 @@ -24,7 +24,8 @@ How to support a new FPGA device
@@ -109,7 +113,7 @@
  .. kernel-doc:: drivers/fpga/fpga-mgr.c
     :functions: fpga_mgr_unregister
 diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
-index 06651389c5926..0f4035b089a2e 100644
+index 8efa67620e21..0c71d91ba7f6 100644
 --- a/drivers/fpga/fpga-mgr.c
 +++ b/drivers/fpga/fpga-mgr.c
 @@ -664,20 +664,16 @@ static struct attribute *fpga_mgr_attrs[] = {
@@ -141,12 +145,12 @@
   */
  struct fpga_manager *fpga_mgr_get(struct device *dev)
  {
--	struct device *mgr_dev = class_find_device(&fpga_mgr_class, NULL, dev,
+-	struct device *mgr_dev = class_find_device(fpga_mgr_class, NULL, dev,
 -						   fpga_mgr_dev_match);
 +	struct fpga_manager *mgr;
 +	struct device *mgr_dev;
 +
-+	mgr_dev = class_find_device(&fpga_mgr_class, NULL, dev, fpga_mgr_dev_match);
++	mgr_dev = class_find_device(fpga_mgr_class, NULL, dev, fpga_mgr_dev_match);
  	if (!mgr_dev)
  		return ERR_PTR(-ENODEV);
  
@@ -167,9 +171,9 @@
 +	struct fpga_manager *mgr;
 +	struct device *mgr_dev;
  
--	dev = class_find_device_by_of_node(&fpga_mgr_class, node);
+-	dev = class_find_device_by_of_node(fpga_mgr_class, node);
 -	if (!dev)
-+	mgr_dev = class_find_device_by_of_node(&fpga_mgr_class, node);
++	mgr_dev = class_find_device_by_of_node(fpga_mgr_class, node);
 +	if (!mgr_dev)
  		return ERR_PTR(-ENODEV);
  
@@ -337,7 +341,7 @@
  static void fpga_mgr_dev_release(struct device *dev)
  {
 diff --git a/include/linux/fpga/fpga-mgr.h b/include/linux/fpga/fpga-mgr.h
-index 54f63459efd6e..0d4fe068f3d8a 100644
+index 54f63459efd6..0d4fe068f3d8 100644
 --- a/include/linux/fpga/fpga-mgr.h
 +++ b/include/linux/fpga/fpga-mgr.h
 @@ -201,6 +201,7 @@ struct fpga_manager_ops {
@@ -393,3 +397,6 @@
 +			 struct module *owner);
  
  #endif /*_LINUX_FPGA_MGR_H */
+-- 
+2.43.0
+
---

Results of testing on various branches:

| Branch                    | Patch Apply | Build Test |
|---------------------------|-------------|------------|
| stable/linux-6.1.y        |  Success    |  Success   |

Re: [PATCH 6.1 1/2] fpga: bridge: add owner module and take its refcount

[Sasha Levin]

[ Sasha's backport helper bot ]

Hi,

The upstream commit SHA1 provided is correct: 1da11f822042eb6ef4b6064dc048f157a7852529

WARNING: Author mismatch between patch and upstream commit:
Backport author: Xiangyu Chen <xiangyu.chen@eng.windriver.com>
Commit author: Marco Pagani <marpagan@redhat.com>


Status in newer kernel trees:
6.12.y | Present (exact SHA1)
6.11.y | Present (exact SHA1)
6.6.y | Present (different SHA1: d7c4081c54a1)
6.1.y | Not found

Note: The patch differs from the upstream commit:
---
--- -	2024-11-25 10:03:24.580903183 -0500
+++ /tmp/tmp.dgudhG3mc3	2024-11-25 10:03:24.569117471 -0500
@@ -1,3 +1,5 @@
+[ Upstream commit 1da11f822042eb6ef4b6064dc048f157a7852529 ]
+
 The current implementation of the fpga bridge assumes that the low-level
 module registers a driver for the parent device and uses its owner pointer
 to take the module's refcount. This approach is problematic since it can
@@ -27,6 +29,8 @@
 Acked-by: Xu Yilun <yilun.xu@intel.com>
 Link: https://lore.kernel.org/r/20240322171839.233864-1-marpagan@redhat.com
 Signed-off-by: Xu Yilun <yilun.xu@linux.intel.com>
+Signed-off-by: Sasha Levin <sashal@kernel.org>
+Signed-off-by: Xiangyu Chen <xiangyu.chen@windriver.com>
 ---
  Documentation/driver-api/fpga/fpga-bridge.rst |  7 ++-
  drivers/fpga/fpga-bridge.c                    | 57 ++++++++++---------
@@ -34,7 +38,7 @@
  3 files changed, 43 insertions(+), 31 deletions(-)
 
 diff --git a/Documentation/driver-api/fpga/fpga-bridge.rst b/Documentation/driver-api/fpga/fpga-bridge.rst
-index 6042085340953..833f68fb07008 100644
+index 604208534095..833f68fb0700 100644
 --- a/Documentation/driver-api/fpga/fpga-bridge.rst
 +++ b/Documentation/driver-api/fpga/fpga-bridge.rst
 @@ -6,9 +6,12 @@ API to implement a new FPGA bridge
@@ -61,7 +65,7 @@
  .. kernel-doc:: drivers/fpga/fpga-bridge.c
     :functions: fpga_bridge_unregister
 diff --git a/drivers/fpga/fpga-bridge.c b/drivers/fpga/fpga-bridge.c
-index 79c473b3c7c3d..8ef395b49bf8a 100644
+index 833ce13ff6f8..698d6cbf782a 100644
 --- a/drivers/fpga/fpga-bridge.c
 +++ b/drivers/fpga/fpga-bridge.c
 @@ -55,33 +55,26 @@ int fpga_bridge_disable(struct fpga_bridge *bridge)
@@ -106,7 +110,7 @@
  }
  
  /**
-@@ -98,13 +91,18 @@ static struct fpga_bridge *__fpga_bridge_get(struct device *dev,
+@@ -97,13 +90,18 @@ static struct fpga_bridge *__fpga_bridge_get(struct device *dev,
  struct fpga_bridge *of_fpga_bridge_get(struct device_node *np,
  				       struct fpga_image_info *info)
  {
@@ -114,9 +118,9 @@
 +	struct fpga_bridge *bridge;
 +	struct device *bridge_dev;
  
--	dev = class_find_device_by_of_node(&fpga_bridge_class, np);
+-	dev = class_find_device_by_of_node(fpga_bridge_class, np);
 -	if (!dev)
-+	bridge_dev = class_find_device_by_of_node(&fpga_bridge_class, np);
++	bridge_dev = class_find_device_by_of_node(fpga_bridge_class, np);
 +	if (!bridge_dev)
  		return ERR_PTR(-ENODEV);
  
@@ -129,15 +133,15 @@
  }
  EXPORT_SYMBOL_GPL(of_fpga_bridge_get);
  
-@@ -125,6 +123,7 @@ static int fpga_bridge_dev_match(struct device *dev, const void *data)
+@@ -124,6 +122,7 @@ static int fpga_bridge_dev_match(struct device *dev, const void *data)
  struct fpga_bridge *fpga_bridge_get(struct device *dev,
  				    struct fpga_image_info *info)
  {
 +	struct fpga_bridge *bridge;
  	struct device *bridge_dev;
  
- 	bridge_dev = class_find_device(&fpga_bridge_class, NULL, dev,
-@@ -132,7 +131,11 @@ struct fpga_bridge *fpga_bridge_get(struct device *dev,
+ 	bridge_dev = class_find_device(fpga_bridge_class, NULL, dev,
+@@ -131,7 +130,11 @@ struct fpga_bridge *fpga_bridge_get(struct device *dev,
  	if (!bridge_dev)
  		return ERR_PTR(-ENODEV);
  
@@ -150,7 +154,7 @@
  }
  EXPORT_SYMBOL_GPL(fpga_bridge_get);
  
-@@ -146,7 +149,7 @@ void fpga_bridge_put(struct fpga_bridge *bridge)
+@@ -145,7 +148,7 @@ void fpga_bridge_put(struct fpga_bridge *bridge)
  	dev_dbg(&bridge->dev, "put\n");
  
  	bridge->info = NULL;
@@ -159,7 +163,7 @@
  	mutex_unlock(&bridge->mutex);
  	put_device(&bridge->dev);
  }
-@@ -316,18 +319,19 @@ static struct attribute *fpga_bridge_attrs[] = {
+@@ -312,18 +315,19 @@ static struct attribute *fpga_bridge_attrs[] = {
  ATTRIBUTE_GROUPS(fpga_bridge);
  
  /**
@@ -183,7 +187,7 @@
  {
  	struct fpga_bridge *bridge;
  	int id, ret;
-@@ -357,6 +361,7 @@ fpga_bridge_register(struct device *parent, const char *name,
+@@ -353,6 +357,7 @@ fpga_bridge_register(struct device *parent, const char *name,
  
  	bridge->name = name;
  	bridge->br_ops = br_ops;
@@ -191,7 +195,7 @@
  	bridge->priv = priv;
  
  	bridge->dev.groups = br_ops->groups;
-@@ -386,7 +391,7 @@ fpga_bridge_register(struct device *parent, const char *name,
+@@ -382,7 +387,7 @@ fpga_bridge_register(struct device *parent, const char *name,
  
  	return ERR_PTR(ret);
  }
@@ -201,7 +205,7 @@
  /**
   * fpga_bridge_unregister - unregister an FPGA bridge
 diff --git a/include/linux/fpga/fpga-bridge.h b/include/linux/fpga/fpga-bridge.h
-index 223da48a6d18b..94c4edd047e54 100644
+index 223da48a6d18..94c4edd047e5 100644
 --- a/include/linux/fpga/fpga-bridge.h
 +++ b/include/linux/fpga/fpga-bridge.h
 @@ -45,6 +45,7 @@ struct fpga_bridge_info {
@@ -236,3 +240,6 @@
  void fpga_bridge_unregister(struct fpga_bridge *br);
  
  #endif /* _LINUX_FPGA_BRIDGE_H */
+-- 
+2.43.0
+
---

Results of testing on various branches:

| Branch                    | Patch Apply | Build Test |
|---------------------------|-------------|------------|
| stable/linux-6.1.y        |  Success    |  Success   |