Merge branch '13-null-pointer-in-the-error-handling-process-of-add_eeprom' into 'master'

Resolve "NULL pointer in the error handling process of add_eeprom"

Closes #13

See merge request be-cem-edl/fec/hardware-modules/fmc!8

drivers/fmc/Kbuild

@@ -12,7 +12,7 @@ endif
 LINUXINCLUDE := -I$(src)/include -I$(src)/../../include -I$(src)/../../include/uapi $(LINUXINCLUDE)
 
 ccflags-y += -DADDITIONAL_VERSIONS="$(SUBMODULE_VERSIONS-y)"
-ccflags-y += -Werror
+ccflags-y += -Werror -ggdb
 ccflags-y += -I$(src)/../../include
 
 obj-$(CONFIG_FMC) = fmc.o

drivers/fmc/fmc-core.c

@@ -87,8 +87,9 @@ static void fmc_slot_release(struct device *dev)
 	struct fmc_slot *slot = to_fmc_slot(dev);
 
 	i2c_put_adapter(slot->adapter);
-
+	slot->adapter = NULL;
 	ida_simple_remove(&fmc_slot_ida, slot->dev.id);
+	slot->dev.id = -1;
 }
 
 static const struct device_type fmc_slot_type = {
@@ -115,6 +116,7 @@ static void fmc_carrier_release(struct device *dev)
 	struct fmc_carrier *carrier = to_fmc_carrier(dev);
 
 	ida_simple_remove(&fmc_carrier_ida, carrier->dev.id);
+	carrier->dev.id = -1;
 }
 
 static const struct device_type fmc_carrier_type = {
@@ -148,39 +150,42 @@ static struct fmc_slot *fmc_carrier_add_slot(struct fmc_carrier *carrier,
 					     struct fmc_slot_info *info)
 {
 	struct fmc_slot *slot;
-	int ret, err, id;
+	int ret, err;
 
 	if (WARN(!info, "Invalid slot info"))
 		return ERR_PTR(-EINVAL);
 
-	id = fmc_slot_id(carrier, info->lun);
-	id = ida_simple_get(&fmc_slot_ida, id, id + 1, GFP_KERNEL);
-	if (id < 0) {
-		dev_err(&carrier->dev,
-			"can't assign ID to slot (LUN: %dGA: 0x%02x)\n",
-			info->lun, info->ga);
-		err = id;
-		goto err_ida;
-	}
-
 	slot = devm_kzalloc(&carrier->dev, sizeof(struct fmc_slot), GFP_KERNEL);
 	if (!slot) {
 		err = -ENOMEM;
 		goto err_alloc;
 	}
 
+
 	slot->ga = info->ga;
 	slot->lun = info->lun;
+	slot->dev.class = &fmc_class;
+	slot->dev.type = &fmc_slot_type;
+	slot->dev.parent = &carrier->dev;
+
+	slot->dev.id = fmc_slot_id(carrier, info->lun);
+	slot->dev.id = ida_simple_get(&fmc_slot_ida,
+				      slot->dev.id, slot->dev.id + 1,
+				      GFP_KERNEL);
+	if (slot->dev.id < 0) {
+		dev_err(&carrier->dev,
+			"can't assign ID to slot (LUN: %dGA: 0x%02x)\n",
+			info->lun, info->ga);
+		err = slot->dev.id;
+		goto err_ida;
+	}
+
 	slot->adapter = i2c_get_adapter(info->i2c_bus_nr);
 	if (!slot->adapter) {
 		err = -ENODEV;
 		goto err_i2c;
 	}
 
-	slot->dev.class = &fmc_class;
-	slot->dev.type = &fmc_slot_type;
-	slot->dev.parent = &carrier->dev;
-	slot->dev.id = id;
 	err = dev_set_name(&slot->dev, "fmc-slot-%d.%d",
 			   carrier->dev.id,
 			   slot->lun);
@@ -209,10 +214,10 @@ err_reg:
 err_name:
 	i2c_put_adapter(slot->adapter);
 err_i2c:
+	ida_simple_remove(&fmc_slot_ida, slot->dev.id);
+err_ida:
 	devm_kfree(&carrier->dev, slot);
 err_alloc:
-	ida_simple_remove(&fmc_slot_ida, id);
-err_ida:
 	return ERR_PTR(err);
 }
 
@@ -248,7 +253,7 @@ int fmc_carrier_register(struct device *parent,
 			 void *priv)
 {
 	struct fmc_carrier *carrier;
-	int err, id, i;
+	int err, i;
 	ssize_t carrier_mem_size;
 	void *tmp_p;
 
@@ -269,13 +274,6 @@ int fmc_carrier_register(struct device *parent,
 		return -EINVAL;
 	}
 
-	id = ida_simple_get(&fmc_carrier_ida, 0, 0, GFP_KERNEL);
-	if (id < 0) {
-		dev_err(parent, "FMC can't assign ID to carrier\n");
-		err = id;
-		goto err_ida;
-	}
-
 	carrier_mem_size = sizeof(struct fmc_carrier);
 	carrier_mem_size += sizeof(struct fmc_slot *) * nr_slot;
 	carrier = devm_kzalloc(parent, carrier_mem_size, GFP_KERNEL);
@@ -292,7 +290,13 @@ int fmc_carrier_register(struct device *parent,
 	carrier->dev.class = &fmc_class;
 	carrier->dev.type = &fmc_carrier_type;
 	carrier->dev.parent = parent;
-	carrier->dev.id = id;
+
+	carrier->dev.id = ida_simple_get(&fmc_carrier_ida, 0, 0, GFP_KERNEL);
+	if (carrier->dev.id < 0) {
+		dev_err(parent, "FMC can't assign ID to carrier\n");
+		err = carrier->dev.id;
+		goto err_ida;
+	}
 	err = dev_set_name(&carrier->dev, "fmc-carrier-%x", carrier->dev.id);
 	if (err)
 		goto err_name;
@@ -320,10 +324,10 @@ err_slot:
 	device_unregister(&carrier->dev);
 err_reg:
 err_name:
+	ida_simple_remove(&fmc_carrier_ida, carrier->dev.id);
+err_ida:
 	devm_kfree(parent, carrier);
 err_alloc:
-	ida_simple_remove(&fmc_carrier_ida, id);
-err_ida:
 	dev_err(parent, "FMC carrier registration: failed %d\n", err);
 	return err;
 }

drivers/fmc/fmc-eeprom.c

@@ -196,6 +196,7 @@ static int __fmc_slot_eeprom_add(struct fmc_slot *slot,
 	if (IS_ERR_OR_NULL(slot->nvmem)) {
 		int err = PTR_ERR(slot->nvmem);
 		slot->nvmem = NULL;
+		dev_err(&slot->dev, "Can't find attached EEPROM (%d)\n", err);
 		return err;
 	}
 #endif