[PATCH] elf: Align argument of __munmap to page size [BZ #28676]

[H.J. Lu]

On Mon, Dec 13, 2021 at 11:40 PM Florian Weimer <fweimer@redhat.com> wrote:
>
> * H. J. Lu via Libc-alpha:
>
> > On Mon, Dec 13, 2021 at 6:49 PM Rongwei Wang
> > <rongwei.wang@linux.alibaba.com> wrote:
> >>
> >> Hi, HJ
> >>
> >> Thanks for your help to fix this bug. And I just found out that the
> >> patch "elf: Properly align PT_LOAD segments" had been merged into
> >> glibc/master.
> >>
> >> And I saw Florian's email:
> >>
> >>  > We should check munmap failure though and rollback everything if
> >>  > necessary.  It's possible we can undo the initial PROT_NONE mapping even
> >>  > if future munmap calls fail because unmapping the first mapping does not
> >>  > need to split a mapping.
> >>
> >> It seems rollback initial PROT_NONE mapping when munmap fails is good
> >> idea. Nice to have. Of course, IMO, this your patch is also can fix this
> >> munmap failure well. what do you think?
> >>
> >> When this fix is stable in glibc upstream, I will backport it into our
> >> internal glibc repo. So, if you have any improve this fix suggestions, I
> >> will respond immediately. Sorry for my speed is much slower than your.
> >>
> >>
> >
> > Let's wait for a few days.
>
> Can we please fix the regression in some way?  It impacts development,
> particularly at this late stage during the 2.34 cycle.
>
> Either revert the change, or at least add the unchecked __munmap, and
> fix that later.

What is the unchecked __munmap?


-- 
H.J.