Question - intention of UCLIBC_BUILD_NOEXECSTACK?

[Andrew McDonnell]

On 25/08/14 22:56, Andrew McDonnell wrote:
> Hmmm, I am having some trouble repeating my original result.
> 
<snipped>

OK, with a fresh build, the following appears to apply:

* OpenWRT sets UCLIBC_BUILD_NOEXECSTACK=y

* Somehow this ends up with libcrypt, libm, libresolv, libnsl, libthread_db,
libdl and  and libutil actually having the NX flag set in the ELF despite
there being no -Wl,-z,noexecstack linker option specified.

This I really do not understand yet!

* ld-uClibc, librt, libuClibc and libpthread _dont have the NX flag set, which
is what I would have expected when the link was missing the noexecstack option.

* The above was checked before any stripping applied, just in case

Now its gotten too late, so I'll have to re-test my patch that applies the
noexecstack marking to ld-uClibc, librt, libuClibc and libpthread as well
later this week before I submit it.

FWIW this is all done using the OpenWRT buildroot for a carambola2 target

There is another oddity with all of this, as well.

Every single one of libcrypt, libm, libresolv, libnsl, libthread_db, libdl,
libutil, libuClibc, librt and libpthread are all built with -Wl,-z-relro yet
the GNU_RELRO section is only present in libdl, libpthread and libuClibc and
yet all are built with exactly the same set of -Wl,-z options

I am wondering if this is this bug,
https://sourceware.org/bugzilla/show_bug.cgi?id=16322 because OpenWRT binutils
is still 2.23


--Andrew

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