[PATCH] nss_files: Fix /etc/aliases null pointer dereference [BZ #24059]

[Florian Weimer]

* Szabolcs Nagy:

> On 15/01/2019 15:54, Florian Weimer wrote:
>> If /etc/aliases ends with a continuation line (a line that starts
>> with whitespace) which does not have a training newline character,
>> the file parser would crash due to a null pointer dereference.
>> 
>> 2019-01-15  Florian Weimer  <fweimer@redhat.com>
>> 
>> 	[BZ #24059]
>> 	* nss/nss_files/files-alias.c (get_next_alias): Handle
>> 	continuation line without newline at the end.
>> 	* nss/tst-nss-files-alias-truncated.c: New file.
>> 	* nss/Makefile [$(build-shared)] (tests): Add
>> 	tst-nss-files-alias-truncated.
>> 	(tst-nss-files-alias-truncated): Link with libnss_files.so.
>> 	* support/namespace.h (struct support_chroot_configuration): Add
>> 	aliases member.
>> 	(struct support_chroot): Add path_aliases member.
>> 	* support/support_chroot.c (support_chroot_create): Handle
>> 	aliases.
>> 	(support_chroot_free): Free path_aliases.
>
> aarch64 buildbot consistently fails with
>
> FAIL: nss/tst-nss-files-alias-truncated
>
> error: tst-nss-files-alias-truncated.c:34: not true: e != NULL
> error: support_isolate_in_subprocess.c:37: child process exited with status 256
> error: 2 test failures
>
> i'm not yet sure why (passes with ./testrun.sh)

I haven't seen that, and I don't know what could be causing it.  I fear
you have to debug it in the context of the build bot, sorry.

Thanks,
Florian