Re: [PATCH] ntb_hw_switchtec: Fix shift-out-of-bounds in switchtec_ntb_mw_set_trans

[Logan Gunthorpe]

On 2023-08-16 02:33, Yajun Deng wrote:
> 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.
> 
> Fixes: 1e2fd202f859 ("ntb_hw_switchtec: Check for alignment of the buffer in mw_set_trans()")
> Signed-off-by: Yajun Deng <yajun.deng@xxxxxxxxx>

That makes sense. Thanks!

Reviewed-by: Logan Gunthorpe <logang@xxxxxxxxxxxx>

Logan