From 5361ad3910c257bc327567be76fde532ed238e42 Mon Sep 17 00:00:00 2001 From: Florian Weimer Date: Fri, 19 Apr 2024 14:38:17 +0200 Subject: login: Use unsigned 32-bit types for seconds-since-epoch These fields store timestamps when the system was running. No Linux systems existed before 1970, so these values are unused. Switching to unsigned types allows continued use of the existing struct layouts beyond the year 2038. The intent is to give distributions more time to switch to improved interfaces that also avoid locking/data corruption issues. Reviewed-by: Adhemerval Zanella --- login/Makefile | 4 +++- login/tst-utmp-unsigned-64.c | 1 + login/tst-utmp-unsigned.c | 40 ++++++++++++++++++++++++++++++++++++++++ 3 files changed, 44 insertions(+), 1 deletion(-) create mode 100644 login/tst-utmp-unsigned-64.c create mode 100644 login/tst-utmp-unsigned.c (limited to 'login') diff --git a/login/Makefile b/login/Makefile index f91190e3dc..84563230ef 100644 --- a/login/Makefile +++ b/login/Makefile @@ -44,9 +44,11 @@ subdir-dirs = programs vpath %.c programs tests := tst-utmp tst-utmpx tst-grantpt tst-ptsname tst-getlogin tst-updwtmpx \ - tst-pututxline-lockfail tst-pututxline-cache tst-utmp-size tst-utmp-size-64 + tst-pututxline-lockfail tst-pututxline-cache tst-utmp-size tst-utmp-size-64 \ + tst-utmp-unsigned tst-utmp-unsigned-64 CFLAGS-tst-utmp-size-64.c += -D_FILE_OFFSET_BITS=64 -D_TIME_BITS=64 +CFLAGS-tst-utmp-unsigned-64.c += -D_FILE_OFFSET_BITS=64 -D_TIME_BITS=64 # Empty compatibility library for old binaries. extra-libs := libutil diff --git a/login/tst-utmp-unsigned-64.c b/login/tst-utmp-unsigned-64.c new file mode 100644 index 0000000000..940e7654f8 --- /dev/null +++ b/login/tst-utmp-unsigned-64.c @@ -0,0 +1 @@ +#include "tst-utmp-unsigned.c" diff --git a/login/tst-utmp-unsigned.c b/login/tst-utmp-unsigned.c new file mode 100644 index 0000000000..27ad03a7d6 --- /dev/null +++ b/login/tst-utmp-unsigned.c @@ -0,0 +1,40 @@ +/* Check that struct utmp, struct utmpx, struct lastlog use unsigned epoch. + Copyright (C) 2024 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include +#include + +/* Undefined. Used to check that the conditions below are optimized away. */ +void link_failure_utmp (void); +void link_failure_utmpx (void); +void link_failure_lastlog (void); + +static int +do_test (void) +{ + if ((struct utmp) { .ut_tv = { 0x80000000U, }, }.ut_tv.tv_sec <= 0) + link_failure_utmp (); + if ((struct utmpx) { .ut_tv = { 0x80000000U, }, }.ut_tv.tv_sec <= 0) + link_failure_utmpx (); + if ((struct lastlog) { .ll_time = 0x80000000U, }.ll_time <= 0) + link_failure_lastlog (); + return 0; +} + +#include -- cgit 1.4.1