fdlopen(3)

[Xin LI]

On Thu, Dec 29, 2011 at 3:38 AM, Kostik Belousov <kostikbel at gmail.com> wrote:
> On Thu, Dec 29, 2011 at 03:15:09AM -0800, Xin LI wrote:
>> Hi,
>>
>> On Thu, Dec 29, 2011 at 12:43 AM, Kostik Belousov <kostikbel at gmail.com> wrote:
>> > Hello,
>> > below is the patch to add fdlopen(3) function to rtld. It allows to load
>> > shared object referenced by the opened file descriptor. Intent is to allow
>> > the caller to do some additional checks on the object before committing
>> > to load it, in race-free manner.
>> >
>> > The facility was requested by des@, who also tested the patch.
>> >
>> > I will commit this shortly unless somebody objects.
>>
>> Will this prevent e.g. writes to the .so file after open, but before fdlopen()?
>
> How can it ? Even in theory ?

e.g. process 1 open(), check for permissions, etc., then process 2
open() for write, write something, then process proceed with
fdlopen()?  (We do not have mandatory "lock" on file handles to
prevent writing I think?).

But no, this is not a "major" concern and yes, I think fdlopen() is
something good to have.

Cheers,
-- 
Xin LI <delphij at delphij.net> https://www.delphij.net/
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