[committed,v3] nisplus: Correct pwent parsing issue and resulting build error [BZ #23266]
Commit Message
Copy and null-terminate NIS+ password file UID and GID entries whose
length is non-zero and are not terminated, in addition to empty ones,
fixing a bug and a compilation issue causing an error with GCC 8:
nss_nisplus/nisplus-parser.c: In function '_nss_nisplus_parse_pwent':
nss_nisplus/nisplus-parser.c:90:7: error: 'strncpy' destination unchanged after copying no bytes [-Werror=stringop-truncation]
strncpy (first_unused, numstr, len);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
nss_nisplus/nisplus-parser.c:106:7: error: 'strncpy' destination unchanged after copying no bytes [-Werror=stringop-truncation]
strncpy (first_unused, numstr, len);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
introduced with commit ac05397075f6:
commit ac05397075f621cfdbe1db527c96167a58b6d18e
Author: Ulrich Drepper <drepper@redhat.com>
Date: Sun Apr 30 07:01:26 2006 +0000
* nis/nss_nisplus/nisplus-parser.c: Minor optimizations and
cleanups. Avoid copying data if it can be used in the old place.
(no mailing list reference available). Obviously regardless of the
recently added compiler diagnostics causing a build error this code has
been long non-functional, so I guess NIS+ servers have been supplying
strings that are non-empty and have already been null-terminated.
Which in turn made it unnecessary to make a null-terminated copy,
masking this bug.
[BZ #23266]
* nis/nss_nisplus/nisplus-parser.c (_nss_nisplus_parse_pwent):
Copy and null-terminate entries that are not terminated, in
addition to empty ones.
---
On Mon, 25 Jun 2018, DJ Delorie wrote:
> > Ping for:
> >
> > <https://patchwork.sourceware.org/patch/27908/>
> >
> > Previous discussion:
> >
> > <https://patchwork.sourceware.org/patch/27906/>
>
> LGTM
Thanks, applied now, with two minor updates:
* s/compilation/build/ in the heading so that it fits in 79 columns with
GIT's indentation applied,
* a comma added after "are not terminated" in the description and
ChangeLog, for clarity,
which I have decided that qualify as trivial and therefore not requiring
further consensus.
Here's the actual version committed, for future reference.
Maciej
---
ChangeLog | 7 +++++++
nis/nss_nisplus/nisplus-parser.c | 4 ++--
2 files changed, 9 insertions(+), 2 deletions(-)
Comments
As usual when committing a fix for a bug, please mark the bug as RESOLVED
/ FIXED in Bugzilla with target milestone set to 2.28.
@@ -82,7 +82,7 @@ _nss_nisplus_parse_pwent (nis_result *result, struct passwd *pw,
char *numstr = NISOBJVAL (2, obj);
len = NISOBJLEN (2, obj);
- if (len == 0 && numstr[len - 1] != '\0')
+ if (len == 0 || numstr[len - 1] != '\0')
{
if (len >= room_left)
goto no_more_room;
@@ -98,7 +98,7 @@ _nss_nisplus_parse_pwent (nis_result *result, struct passwd *pw,
numstr = NISOBJVAL (3, obj);
len = NISOBJLEN (3, obj);
- if (len == 0 && numstr[len - 1] != '\0')
+ if (len == 0 || numstr[len - 1] != '\0')
{
if (len >= room_left)
goto no_more_room;