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From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
To: Florian Weimer <fweimer@redhat.com>
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 17:02:11 -0300	[thread overview]
Message-ID: <ad4a90cf-612a-f22a-72cd-2c5aa1ac074d@linaro.org> (raw)
In-Reply-To: <871r3ddykc.fsf@oldenburg.str.redhat.com>



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?

  reply	other threads:[~2021-11-18 20:02 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 [this message]
2021-11-18 20:05     ` Florian Weimer

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