Re: [syzbot] Re: [syzbot] [bluetooth?] KASAN: vmalloc-out-of-bounds Read in hci_devcd_dump

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***

Subject: Re: [syzbot] [bluetooth?] KASAN: vmalloc-out-of-bounds Read in hci_devcd_dump
Author: ipravdin.official@gmail.com

#syz test

diff --git a/net/bluetooth/coredump.c b/net/bluetooth/coredump.c
index 819eacb38762..720cb79adf96 100644
--- a/net/bluetooth/coredump.c
+++ b/net/bluetooth/coredump.c
@@ -249,15 +249,15 @@ static void hci_devcd_dump(struct hci_dev *hdev)
 
        size = hdev->dump.tail - hdev->dump.head;
 
-       /* Emit a devcoredump with the available data */
-       dev_coredumpv(&hdev->dev, hdev->dump.head, size, GFP_KERNEL);
-
        /* Send a copy to monitor as a diagnostic packet */
        skb = bt_skb_alloc(size, GFP_ATOMIC);
        if (skb) {
                skb_put_data(skb, hdev->dump.head, size);
                hci_recv_diag(hdev, skb);
        }
+
+       /* Emit a devcoredump with the available data */
+       dev_coredumpv(&hdev->dev, hdev->dump.head, size, GFP_KERNEL);
 }

Ivan Pravdin