Re: [PATCH 1/3] xen/livepatch: simplify and unify logic in prepare_payload()

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

On 23/09/2024 8:46 am, Roger Pau Monné wrote:
> On Sun, Sep 22, 2024 at 11:19:01AM +0200, Andrew Cooper wrote:
>> On 20/09/2024 11:36 am, Roger Pau Monne wrote:
>>> +{
>>> +    const Elf_Note *n = sec->load_addr;
>>> +    int rc;
>>> +
>>> +    ASSERT(sec);
>> This needs to turn back into a runtime check.  Now, if a livepatch is
>> missing one of the sections, we'll dereference NULL below, rather than
>> leaving no data in the struct livepatch_build_id.
> Loading should never get here without those sections being present,
> check_special_sections() called earlier will return error if any of
> the sections is not present, hence the ASSERT() is fine IMO.

Ah, in which case, can we please have:

/* Existence of note sections already confirmed in
check_special_sections() */
ASSERT(sec);

Just to show that someone did think about the provenance of the pointer,
and where to look to check.

With this and the rename, Reviewed-by: Andrew Cooper
<andrew.cooper3@xxxxxxxxxx>