HID: hidraw: add proper error handling to raw event reporting

If kmemdup() in hidraw_report_event() fails, we are not propagating
this fact properly.

Let hidraw_report_event() and hid_report_raw_event() return an error
value to the caller.

Reported-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

4 files changed, 27 insertions, 14 deletions

diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 8be458b79b2c..0cddcaa3fe7f 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -1032,7 +1032,7 @@ static struct hid_report *hid_get_report(struct hid_report_enum *report_enum,
         return report;
 }
 
-void hid_report_raw_event(struct hid_device *hid, int type, u8 *data, int size,
+int hid_report_raw_event(struct hid_device *hid, int type, u8 *data, int size,
                 int interrupt)
 {
         struct hid_report_enum *report_enum = hid->report_enum + type;
@@ -1040,10 +1040,11 @@ void hid_report_raw_event(struct hid_device *hid, int type, u8 *data, int size,
         unsigned int a;
         int rsize, csize = size;
         u8 *cdata = data;
+        int ret = 0;
 
         report = hid_get_report(report_enum, data);
         if (!report)
-                return;
+                goto out;
 
         if (report_enum->numbered) {
                 cdata++;
@@ -1063,14 +1064,19 @@ void hid_report_raw_event(struct hid_device *hid, int type, u8 *data, int size,
 
         if ((hid->claimed & HID_CLAIMED_HIDDEV) && hid->hiddev_report_event)
                 hid->hiddev_report_event(hid, report);
-        if (hid->claimed & HID_CLAIMED_HIDRAW)
-                hidraw_report_event(hid, data, size);
+        if (hid->claimed & HID_CLAIMED_HIDRAW) {
+                ret = hidraw_report_event(hid, data, size);
+                if (ret)
+                        goto out;
+        }
 
         for (a = 0; a < report->maxfield; a++)
                 hid_input_field(hid, report->field[a], cdata, interrupt);
 
         if (hid->claimed & HID_CLAIMED_INPUT)
                 hidinput_report_event(hid, report);
+out:
+        return ret;
 }
 EXPORT_SYMBOL_GPL(hid_report_raw_event);
 
@@ -1147,7 +1153,7 @@ nomem:
                 }
         }
 
-        hid_report_raw_event(hid, type, data, size, interrupt);
+        ret = hid_report_raw_event(hid, type, data, size, interrupt);
 
 unlock:
         up(&hid->driver_lock);
diff --git a/drivers/hid/hidraw.c b/drivers/hid/hidraw.c
index cf7d6d58e79f..36fa77b40ffb 100644
--- a/drivers/hid/hidraw.c
+++ b/drivers/hid/hidraw.c
@@ -87,11 +87,13 @@ static ssize_t hidraw_read(struct file *file, char __user *buffer, size_t count,
                 len = list->buffer[list->tail].len > count ?
                         count : list->buffer[list->tail].len;
 
-                if (copy_to_user(buffer, list->buffer[list->tail].value, len)) {
-                        ret = -EFAULT;
-                        goto out;
+                if (list->buffer[list->tail].value) {
+                        if (copy_to_user(buffer, list->buffer[list->tail].value, len)) {
+                                ret = -EFAULT;
+                                goto out;
+                        }
+                        ret = len;
                 }
-                ret = len;
 
                 kfree(list->buffer[list->tail].value);
                 list->tail = (list->tail + 1) & (HIDRAW_BUFFER_SIZE - 1);
@@ -437,19 +439,24 @@ static const struct file_operations hidraw_ops = {
         .llseek =       noop_llseek,
 };
 
-void hidraw_report_event(struct hid_device *hid, u8 *data, int len)
+int hidraw_report_event(struct hid_device *hid, u8 *data, int len)
 {
         struct hidraw *dev = hid->hidraw;
         struct hidraw_list *list;
+        int ret = 0;
 
         list_for_each_entry(list, &dev->list, node) {
-                list->buffer[list->head].value = kmemdup(data, len, GFP_ATOMIC);
+                if (!(list->buffer[list->head].value = kmemdup(data, len, GFP_ATOMIC))) {
+                        ret = -ENOMEM;
+                        break;
+                }
                 list->buffer[list->head].len = len;
                 list->head = (list->head + 1) & (HIDRAW_BUFFER_SIZE - 1);
                 kill_fasync(&list->fasync, SIGIO, POLL_IN);
         }
 
         wake_up_interruptible(&dev->wait);
+        return ret;
 }
 EXPORT_SYMBOL_GPL(hidraw_report_event);
 
diff --git a/include/linux/hid.h b/include/linux/hid.h
index 3a95da60fd3e..58b3857dc51c 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -896,7 +896,7 @@ static inline int hid_hw_power(struct hid_device *hdev, int level)
         return hdev->ll_driver->power ? hdev->ll_driver->power(hdev, level) : 0;
 }
 
-void hid_report_raw_event(struct hid_device *hid, int type, u8 *data, int size,
+int hid_report_raw_event(struct hid_device *hid, int type, u8 *data, int size,
                 int interrupt);
 
 extern int hid_generic_init(void);
diff --git a/include/linux/hidraw.h b/include/linux/hidraw.h
index 4b88e697c4e9..9cdc9b67ff49 100644
--- a/include/linux/hidraw.h
+++ b/include/linux/hidraw.h
@@ -76,13 +76,13 @@ struct hidraw_list {
 #ifdef CONFIG_HIDRAW
 int hidraw_init(void);
 void hidraw_exit(void);
-void hidraw_report_event(struct hid_device *, u8 *, int);
+int hidraw_report_event(struct hid_device *, u8 *, int);
 int hidraw_connect(struct hid_device *);
 void hidraw_disconnect(struct hid_device *);
 #else
 static inline int hidraw_init(void) { return 0; }
 static inline void hidraw_exit(void) { }
-static inline void hidraw_report_event(struct hid_device *hid, u8 *data, int len) { }
+static inline int hidraw_report_event(struct hid_device *hid, u8 *data, int len) { }
 static inline int hidraw_connect(struct hid_device *hid) { return -1; }
 static inline void hidraw_disconnect(struct hid_device *hid) { }
 #endif