We are releasing a single msgid, so the order argument to bitmap_release_region must be zero. In practice this was probably harmlessly masked to 0 anyway, which is why it worked, but it trips ubsan. Fixes: 8a06127602de ("Bluetooth: hci_bcm4377: Add new driver for BCM4377 PCIe boards") Reported-by: Aditya Garg <gargaditya08@xxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Hector Martin <marcan@xxxxxxxxx> --- drivers/bluetooth/hci_bcm4377.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/bluetooth/hci_bcm4377.c b/drivers/bluetooth/hci_bcm4377.c index 19ad0e788646..5e9f79235cde 100644 --- a/drivers/bluetooth/hci_bcm4377.c +++ b/drivers/bluetooth/hci_bcm4377.c @@ -715,7 +715,7 @@ static void bcm4377_handle_ack(struct bcm4377_data *bcm4377, ring->events[msgid] = NULL; } - bitmap_release_region(ring->msgids, msgid, ring->n_entries); + bitmap_release_region(ring->msgids, msgid, 0); unlock: spin_unlock_irqrestore(&ring->lock, flags); --- base-commit: ffc253263a1375a65fa6c9f62a893e9767fbebfa change-id: 20231114-bluetooth-msgid-fix-29769be7e45b Best regards, -- Hector Martin <marcan@xxxxxxxxx>