Re: [PATCH] mtd: intel-dg: fix array-index-out-of-bounds in intel_dg_mtd_probe()

Gustavo A. R. Silva
2025-12-20T07:12:50Z

On 12/20/25 16:07, Raag Jadav wrote:
> On Sat, Dec 20, 2025 at 03:41:49PM +0900, Gustavo A. R. Silva wrote:
>> Fix the UBSAN: array-index-out-of-bounds issue below by updating
>> counter nvm->nregions before the first access to flexible-array
>> member nvm->regions[].
>>
>> from kernel bugzilla:
>> https://bugzilla.kernel.org/show_bug.cgi?id=220823
>>
>> Dec 15 22:01:52 orpheus kernel: UBSAN: array-index-out-of-bounds in /var/tmp/portage/sys-kernel/gentoo-kernel-6.18.1/work/linux-6.18/drivers/mtd/devices/mtd_intel_dg.c:750:15
>>
>> Notice that this flexible array is annotated with the counted_by()
>> attribute, hence the counter must always be updated before the
>> first access to the array.
>
> Already fixed[1], but not sure if it's landed yet.
>
> [1] https://lore.kernel.org/linux-mtd/20251111-mtd-nregions-v1-1-61db61e78c63@intel.com/

Great! :)

Thanks
-Gustavo