From: Florian Weimer <fweimer@redhat.com>
To: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Cc: libc-alpha@sourceware.org, "H . J . Lu" <hjl.tools@gmail.com>
Subject: Re: [RFC] elf: Add elf checks for main executable
Date: Thu, 18 Nov 2021 21:05:54 +0100 [thread overview]
Message-ID: <87o86hcjq5.fsf@oldenburg.str.redhat.com> (raw)
In-Reply-To: <ad4a90cf-612a-f22a-72cd-2c5aa1ac074d@linaro.org> (Adhemerval Zanella's message of "Thu, 18 Nov 2021 17:02:11 -0300")
* Adhemerval Zanella:
> On 18/11/2021 17:00, Florian Weimer wrote:
>> * Adhemerval Zanella:
>>
>>> +static inline void
>>> +_dl_check_ehdr (struct link_map *main_map)
>>> +{
>>> + ElfW(Ehdr) *ehdr = (void *) main_map->l_map_start;
>>> + int err = _dl_elfhdr_check (ehdr);
>>> + if (err != DL_ELFHDR_OK)
>>> + _dl_fatal_printf ("program loading error: %s\n", _dl_elfhdr_errstr (err));
>>> +}
>>
>> I think you need to iterate through the load segments and see if there
>> is one with p_offset == 0 and p_memsz > 0 (the ELF header is smaller
>> than a page). That's the one to use for this check. If there is no
>> such segment, we have to skip the check.
>
> Hum, should we set the l_map_start as well only if we found such segment?
No, we need l_map_start in _dl_find_dso_for_object (among other places).
Thanks,
Florian
prev parent reply other threads:[~2021-11-18 20:06 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-11-18 19:55 Adhemerval Zanella
2021-11-18 19:58 ` H.J. Lu
2021-11-18 20:00 ` Adhemerval Zanella
2021-11-18 20:01 ` Florian Weimer
2021-11-18 20:03 ` Adhemerval Zanella
2021-11-18 20:08 ` H.J. Lu
2021-11-19 1:06 ` H.J. Lu
2021-11-18 20:00 ` Florian Weimer
2021-11-18 20:02 ` Adhemerval Zanella
2021-11-18 20:05 ` Florian Weimer [this message]
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