2 files changed, 24 insertions, 8 deletions

diff --git a/drivers/hid/bpf/hid_bpf_dispatch.c b/drivers/hid/bpf/hid_bpf_dispatch.c
index 68a9a2fcbc06..5174dc6d9d18 100644
--- a/drivers/hid/bpf/hid_bpf_dispatch.c
+++ b/drivers/hid/bpf/hid_bpf_dispatch.c
@@ -496,24 +496,32 @@ hid_bpf_hw_output_report(struct hid_bpf_ctx *ctx, __u8 *buf, size_t buf__sz)
  * @buf: a %PTR_TO_MEM buffer
  * @buf__sz: the size of the data to transfer
  *
- * Returns %0 on success, a negative error code otherwise.
+ * Returns %0 on success, a negative error code otherwise. This function will wait for the
+ * device to be available before injecting the event, thus needs to be called in sleepable
+ * context.
  */
 __bpf_kfunc int
 hid_bpf_input_report(struct hid_bpf_ctx *ctx, enum hid_report_type type, u8 *buf,
 		     const size_t buf__sz)
 {
-	struct hid_device *hdev;
 	size_t size = buf__sz;
 	int ret;
 
+	ret = down_interruptible(&ctx->hid->driver_input_lock);
+	if (ret)
+		return ret;
+
 	/* check arguments */
 	ret = __hid_bpf_hw_check_params(ctx, buf, &size, type);
 	if (ret)
 		return ret;
 
-	hdev = (struct hid_device *)ctx->hid; /* discard const */
+	ret = hid_ops->hid_input_report(ctx->hid, type, buf, size, 0, (__u64)ctx,
+					true /* lock_already_taken */);
+
+	up(&ctx->hid->driver_input_lock);
 
-	return hid_ops->hid_input_report(hdev, type, buf, size, 0, (__u64)ctx);
+	return ret;
 }
 __bpf_kfunc_end_defs();
 
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index bb6f334f05bd..e9b5f44683fd 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -2027,7 +2027,8 @@ EXPORT_SYMBOL_GPL(hid_report_raw_event);
 
 
 static int __hid_input_report(struct hid_device *hid, enum hid_report_type type,
-			      u8 *data, u32 size, int interrupt, u64 source)
+			      u8 *data, u32 size, int interrupt, u64 source,
+			      bool lock_already_taken)
 {
 	struct hid_report_enum *report_enum;
 	struct hid_driver *hdrv;
@@ -2037,8 +2038,13 @@ static int __hid_input_report(struct hid_device *hid, enum hid_report_type type,
 	if (!hid)
 		return -ENODEV;
 
-	if (down_trylock(&hid->driver_input_lock))
+	ret = down_trylock(&hid->driver_input_lock);
+	if (lock_already_taken && !ret) {
+		up(&hid->driver_input_lock);
+		return -EINVAL;
+	} else if (!lock_already_taken && ret) {
 		return -EBUSY;
+	}
 
 	if (!hid->driver) {
 		ret = -ENODEV;
@@ -2079,7 +2085,8 @@ static int __hid_input_report(struct hid_device *hid, enum hid_report_type type,
 	ret = hid_report_raw_event(hid, type, data, size, interrupt);
 
 unlock:
-	up(&hid->driver_input_lock);
+	if (!lock_already_taken)
+		up(&hid->driver_input_lock);
 	return ret;
 }
 
@@ -2097,7 +2104,8 @@ unlock:
 int hid_input_report(struct hid_device *hid, enum hid_report_type type, u8 *data, u32 size,
 		     int interrupt)
 {
-	return __hid_input_report(hid, type, data, size, interrupt, 0);
+	return __hid_input_report(hid, type, data, size, interrupt, 0,
+				  false /* lock_already_taken */);
 }
 EXPORT_SYMBOL_GPL(hid_input_report);