[pushed] Remove all loaded objects if dlopen fails, ignoring NODELETE [BZ #20839]

[Szabolcs Nagy]

On 27/11/2019 20:30, Sourceware to Gerrit sync (Code Review) wrote:
> Sourceware to Gerrit sync has submitted this change.
> 
> Change URL: https://gnutoolchain-gerrit.osci.io/r/c/glibc/+/471
> ......................................................................
> 
> Remove all loaded objects if dlopen fails, ignoring NODELETE [BZ #20839]
> 
> This introduces a “pending NODELETE” state in the link map, which is
> flipped to the persistent NODELETE state late in dlopen, via
> activate_nodelete.    During initial relocation, symbol binding
> records pending NODELETE state only.  dlclose ignores pending NODELETE
> state.  Taken together, this results that a partially completed dlopen
> is rolled back completely because new NODELETE mappings are unloaded.
> 
> Tested on x86_64-linux-gnu and i386-linux-gnu.
> 
> Change-Id: Ib2a3d86af6f92d75baca65431d74783ee0dbc292
> ---
> M elf/Makefile
> M elf/dl-close.c
> M elf/dl-lookup.c
> M elf/dl-open.c
> M elf/get-dynamic-info.h
> A elf/tst-dlopenfail.c
> A elf/tst-dlopenfaillinkmod.c
> A elf/tst-dlopenfailmod1.c
> A elf/tst-dlopenfailmod2.c
> M include/link.h
> 10 files changed, 328 insertions(+), 38 deletions(-)
> 
> Approvals:
>   Carlos O'Donell: Looks good to me, approved

i see

FAIL: elf/tst-dlopenfail

and

$ cat elf/tst-dlopenfail.out
info: attempting to load tst-dlopenfailmod1.so
tst-dlopenfailmod1 constructor executed

on the aarch64 buildbot