Re: [PATCH] ACPI: IORT: validate RMR node array bounds

Hanjun Guo <[email protected]> Tue, 4 Aug 2026 11:40:50 +0800
Newsgroups gmane.linux.acpi.devel,gmane.linux.ports.arm.kernel,gmane.linux.kernel
Message-ID <[email protected]>
Hi Will,

On 2026/7/31 23:42, Will Deacon wrote:
> On Mon, Jul 06, 2026 at 05:43:00PM +0800, Pengpeng Hou wrote:
>> IORT RMR nodes describe reserved-memory ranges through firmware
>> offset and count fields inside the current IORT node.
>>
>> Validate the generic IORT node length before dispatching it, and
>> check both the RMR descriptor array and the ID mapping array before
>> walking them.  This binds each array walk to the current node length
>> instead of only trusting the firmware-provided count.
>>
>> Signed-off-by: Pengpeng Hou <[email protected]>
>> ---
>>   drivers/acpi/arm64/iort.c | 83 +++++++++++++++++++++++++++++++++++++--
>>   1 file changed, 79 insertions(+), 4 deletions(-)
> 
> Hanjun, Lorenzo, any thoughts on this one?

Thanks for reminding.

In my personal opinion, this is not a real issue because if something
wrong with the IORT, the IORT will not work at booting, for example
the device will map to a wrong ITS or SMMU, the device will not work
at all, so those issues will be fixed at the pre-production stage,
correct me if I'm wrong.

But to the patch itself, it's no harm, I will comment on this patch.

Thanks
Hanjun