CVE-2023-53034: Out-of-bounds Read

In the Linux kernel, the following vulnerability has been resolved:

ntb_hw_switchtec: Fix shift-out-of-bounds in switchtec_ntb_mw_set_trans

There is a kernel API ntb_mw_clear_trans() would pass 0 to both addr and size. This would make xlate_pos negative.

[ 23.734156] switchtec switchtec0: MW 0: part 0 addr 0x0000000000000000 size 0x0000000000000000 [ 23.734158] ================================================================================ [ 23.734172] UBSAN: shift-out-of-bounds in drivers/ntb/hw/mscc/ntb_hw_switchtec.c:293:7 [ 23.734418] shift exponent -1 is negative

Ensuring xlate_pos is a positive or zero before BIT.