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From: "fweimer at redhat dot com" <sourceware-bugzilla@sourceware.org>
To: glibc-bugs@sourceware.org
Subject: [Bug dynamic-link/31076] Extra struct vm_area_struct with ---p
 created when PAGE_SIZE < max-page-size
Date: Mon, 27 Nov 2023 17:19:25 +0000
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https://sourceware.org/bugzilla/show_bug.cgi?id=3D31076

--- Comment #8 from Florian Weimer <fweimer at redhat dot com> ---
(In reply to Adhemerval Zanella from comment #7)
> So the mprotect is essentially a hardening feature, assuming that the
> dynamic object padding/holes might contain gadgets.  It still does not
> happen for loader and main program itself, since normally they would be
> mapped by the kernel and its does do anything with holes,

There's no expectation that these are contiguous in memory, yes. Such an
expectation exists for shared objects loaded by glibc.

> and IMHO it should
> up to the static linker to fill the padding with NOP/trap instruction to
> avoid such issues.=20

That requires padding to the maximum page size on disk, though.

--=20
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