1 files changed, 20 insertions, 20 deletions

diff --git a/drivers/hid/bpf/hid_bpf_jmp_table.c b/drivers/hid/bpf/hid_bpf_jmp_table.c
index eca34b7372f9..aa8e1c79cdf5 100644
--- a/drivers/hid/bpf/hid_bpf_jmp_table.c
+++ b/drivers/hid/bpf/hid_bpf_jmp_table.c
@@ -196,6 +196,7 @@ static void __hid_bpf_do_release_prog(int map_fd, unsigned int idx)
 static void hid_bpf_release_progs(struct work_struct *work)
 {
 	int i, j, n, map_fd = -1;
+	bool hdev_destroyed;
 
 	if (!jmp_table.map)
 		return;
@@ -220,6 +221,12 @@ static void hid_bpf_release_progs(struct work_struct *work)
 		if (entry->hdev) {
 			hdev = entry->hdev;
 			type = entry->type;
+			/*
+			 * hdev is still valid, even if we are called after hid_destroy_device():
+			 * when hid_bpf_attach() gets called, it takes a ref on the dev through
+			 * bus_find_device()
+			 */
+			hdev_destroyed = hdev->bpf.destroyed;
 
 			hid_bpf_populate_hdev(hdev, type);
 
@@ -232,12 +239,19 @@ static void hid_bpf_release_progs(struct work_struct *work)
 				if (test_bit(next->idx, jmp_table.enabled))
 					continue;
 
-				if (next->hdev == hdev && next->type == type)
+				if (next->hdev == hdev && next->type == type) {
+					/*
+					 * clear the hdev reference and decrement the device ref
+					 * that was taken during bus_find_device() while calling
+					 * hid_bpf_attach()
+					 */
 					next->hdev = NULL;
+					put_device(&hdev->dev);
+				}
 			}
 
-			/* if type was rdesc fixup, reconnect device */
-			if (type == HID_BPF_PROG_TYPE_RDESC_FIXUP)
+			/* if type was rdesc fixup and the device is not gone, reconnect device */
+			if (type == HID_BPF_PROG_TYPE_RDESC_FIXUP && !hdev_destroyed)
 				hid_bpf_reconnect(hdev);
 		}
 	}
@@ -333,15 +347,10 @@ static int hid_bpf_insert_prog(int prog_fd, struct bpf_prog *prog)
 	return err;
 }
 
-int hid_bpf_get_prog_attach_type(int prog_fd)
+int hid_bpf_get_prog_attach_type(struct bpf_prog *prog)
 {
-	struct bpf_prog *prog = NULL;
-	int i;
 	int prog_type = HID_BPF_PROG_TYPE_UNDEF;
-
-	prog = bpf_prog_get(prog_fd);
-	if (IS_ERR(prog))
-		return PTR_ERR(prog);
+	int i;
 
 	for (i = 0; i < HID_BPF_PROG_TYPE_MAX; i++) {
 		if (hid_bpf_btf_ids[i] == prog->aux->attach_btf_id) {
@@ -350,8 +359,6 @@ int hid_bpf_get_prog_attach_type(int prog_fd)
 		}
 	}
 
-	bpf_prog_put(prog);
-
 	return prog_type;
 }
 
@@ -388,19 +395,13 @@ static const struct bpf_link_ops hid_bpf_link_lops = {
 /* called from syscall */
 noinline int
 __hid_bpf_attach_prog(struct hid_device *hdev, enum hid_bpf_prog_type prog_type,
-		      int prog_fd, __u32 flags)
+		      int prog_fd, struct bpf_prog *prog, __u32 flags)
 {
 	struct bpf_link_primer link_primer;
 	struct hid_bpf_link *link;
-	struct bpf_prog *prog = NULL;
 	struct hid_bpf_prog_entry *prog_entry;
 	int cnt, err = -EINVAL, prog_table_idx = -1;
 
-	/* take a ref on the prog itself */
-	prog = bpf_prog_get(prog_fd);
-	if (IS_ERR(prog))
-		return PTR_ERR(prog);
-
 	mutex_lock(&hid_bpf_attach_lock);
 
 	link = kzalloc(sizeof(*link), GFP_USER);
@@ -467,7 +468,6 @@ __hid_bpf_attach_prog(struct hid_device *hdev, enum hid_bpf_prog_type prog_type,
  err_unlock:
 	mutex_unlock(&hid_bpf_attach_lock);
 
-	bpf_prog_put(prog);
 	kfree(link);
 
 	return err;