glibc/include
Adhemerval Zanella d40ac01cbb stdlib: Make abort/_Exit AS-safe (BZ 26275)
The recursive lock used on abort does not synchronize with a new process
creation (either by fork-like interfaces or posix_spawn ones), nor it
is reinitialized after fork().

Also, the SIGABRT unblock before raise() shows another race condition,
where a fork or posix_spawn() call by another thread, just after the
recursive lock release and before the SIGABRT signal, might create
programs with a non-expected signal mask.  With the default option
(without POSIX_SPAWN_SETSIGDEF), the process can see SIG_DFL for
SIGABRT, where it should be SIG_IGN.

To fix the AS-safe, raise() does not change the process signal mask,
and an AS-safe lock is used if a SIGABRT is installed or the process
is blocked or ignored.  With the signal mask change removal,
there is no need to use a recursive loc.  The lock is also taken on
both _Fork() and posix_spawn(), to avoid the spawn process to see the
abort handler as SIG_DFL.

A read-write lock is used to avoid serialize _Fork and posix_spawn
execution.  Both sigaction (SIGABRT) and abort() requires to lock
as writer (since both change the disposition).

The fallback is also simplified: there is no need to use a loop of
ABORT_INSTRUCTION after _exit() (if the syscall does not terminate the
process, the system is broken).

The proposed fix changes how setjmp works on a SIGABRT handler, where
glibc does not save the signal mask.  So usage like the below will now
always abort.

  static volatile int chk_fail_ok;
  static jmp_buf chk_fail_buf;

  static void
  handler (int sig)
  {
    if (chk_fail_ok)
      {
        chk_fail_ok = 0;
        longjmp (chk_fail_buf, 1);
      }
    else
      _exit (127);
  }
  [...]
  signal (SIGABRT, handler);
  [....]
  chk_fail_ok = 1;
  if (! setjmp (chk_fail_buf))
    {
      // Something that can calls abort, like a failed fortify function.
      chk_fail_ok = 0;
      printf ("FAIL\n");
    }

Such cases will need to use sigsetjmp instead.

The _dl_start_profile calls sigaction through _profil, and to avoid
pulling abort() on loader the call is replaced with __libc_sigaction.

Checked on x86_64-linux-gnu and aarch64-linux-gnu.

Reviewed-by: DJ Delorie <dj@redhat.com>
2024-10-08 14:40:12 -03:00
..
arpa Fix all the remaining misspellings -- BZ 25337 2023-06-02 01:39:48 +00:00
bits stdlib: Make abort/_Exit AS-safe (BZ 26275) 2024-10-08 14:40:12 -03:00
gnu Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
net
netinet nss_files: Consolidate line parse declarations in <nss_files.h> 2020-07-21 07:33:20 +02:00
programs Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
protocols
rpc Handle out-of-memory case in svc_tcp.c/svc_unix.c:rendezvous_request. 2020-12-10 11:11:20 +01:00
rpcsvc Remove --enable-obsolete-nsl configure flag 2020-07-08 17:25:57 +02:00
sys Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
aio.h Linux: Move aio_suspend, aio_suspend64, __aio_suspend_time64 to libc 2021-06-25 11:55:27 +02:00
aliases.h Move 'aliases' routines from 'inet' into 'nss' 2023-10-24 12:30:59 +02:00
alloc_buffer.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
alloca.h Remove macros extend_alloca, extend_alloca_account [BZ #18023] 2018-06-27 19:20:37 +02:00
allocate_once.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
ar.h Add missing header wrappers under include/ 2019-02-16 08:25:16 +01:00
argp-fmtstream.h Mark internal argp functions with attribute_hidden [BZ #18822] 2017-10-01 15:10:27 -07:00
argp.h ldbl-opt: Add argp_error and argp_failure (bug 23983) 2019-03-01 15:21:32 -03:00
argz.h Use libc_hidden_* for argz_next, __argz_next (bug 15105). 2018-02-15 21:00:02 +00:00
array_length.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
assert.h assert: Do not use stderr in libc-internal assert 2022-08-03 11:43:04 +02:00
atomic_wide_counter.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
atomic.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
byteswap.h
clone_internal.h posix: Add pidfd_spawn and pidfd_spawnp (BZ 30349) 2023-09-05 13:08:59 -03:00
complex.h
cpio.h
ctype.h Use libc_hidden_* for tolower, toupper (bug 15105). 2018-02-23 13:54:53 +00:00
des.h
dirent.h Use 64 bit time_t stat internally 2021-06-22 12:09:52 -03:00
dlfcn.h arm: Use _dl_find_object on __gnu_Unwind_Find_exidx (BZ 31405) 2024-02-23 08:50:00 -03:00
dso_handle.h Mark __dso_handle as hidden [BZ #18822] 2017-09-26 16:53:44 -07:00
elf.h elf: Refuse to dlopen PIE objects [BZ #24323] 2019-06-18 16:42:10 +02:00
endian.h
envz.h
err.h ldbl-128ibm-compat: PLT redirects for using ldbl redirects internally 2020-03-25 14:34:23 -05:00
errno.h stdlib: Do not use GLIBC_PRIVATE ABI for errno in libc_nonshared.a 2024-09-06 14:07:00 +02:00
error.h Mark various cold functions as __COLD 2023-05-01 19:33:21 +02:00
execinfo.h
fcntl.h Fix Linux fcntl OFD locks for non-LFS architectures (BZ#20251) 2018-06-26 13:22:53 -03:00
features-time64.h y2038: Add support for 64-bit time on legacy ABIs 2021-06-15 10:42:11 -03:00
features.h Increase version number to 2.40 2024-07-21 18:23:25 +02:00
fenv.h Move fenv.h soft-float inlines from fenv_private.h to include/fenv.h. 2018-09-04 19:52:06 +00:00
file_change_detection.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
filename.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
float.h Make totalorder and totalordermag functions take pointer arguments. 2019-08-15 15:18:34 +00:00
fmtmsg.h
fnmatch.h
fpu_control.h Hide internal __setfpucw function [BZ #18822] 2017-10-01 17:52:15 -07:00
fstab.h Add missing header wrappers under include/ 2019-02-16 08:25:16 +01:00
fts.h io: Add fts64 with 64-bit time_t support 2021-06-15 10:42:11 -03:00
ftw.h io: Add ftw64 with 64-bit time_t support 2021-06-15 10:42:11 -03:00
gconv.h
getopt_int.h
getopt.h
glob.h Fix extra PLT reference in libc.so due to __glob64_time64 if build with gcc 7.5 on 32bit. 2021-07-01 16:46:59 +02:00
gmp.h Apply asm redirection in gmp.h before first use 2022-11-07 10:40:21 -03:00
gnu-versions.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
grp-merge.h Remove 'grp' and merge into 'nss' and 'posix' 2023-10-24 12:30:59 +02:00
grp.h Remove 'grp' and merge into 'nss' and 'posix' 2023-10-24 12:30:59 +02:00
gshadow.h Remove 'gshadow' and merge into 'nss' 2023-10-24 12:30:59 +02:00
iconv.h
idx.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
ifaddrs.h nscd: Do not rebuild getaddrinfo (bug 30709) 2023-08-11 10:10:16 +02:00
ifreq.h Hide internal __ifreq function [BZ #18822] 2017-10-01 17:35:46 -07:00
ifunc-impl-list.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
inline-hashtab.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
intprops.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
inttypes.h Make strtoimax, strtoumax, wcstoimax, wcstoumax into aliases 2020-12-08 18:15:27 +00:00
langinfo.h
lastlog.h Add missing header wrappers under include/ 2019-02-16 08:25:16 +01:00
libc-diag.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
libc-internal.h Define __libc_initial for the static libc 2024-08-09 16:17:14 +02:00
libc-pointer-arith.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
libc-symbols.h riscv: Enable multi-arg ifunc resolvers 2024-03-01 07:14:59 -08:00
libgen.h
libintl.h Document the internal _ and N_ macros 2020-05-06 17:35:40 +02:00
limits.h Refer to C23 in place of C2X in glibc 2024-02-01 11:02:01 +00:00
link.h elf: Avoid re-initializing already allocated TLS in dlopen (bug 31717) 2024-08-05 18:26:52 +02:00
list_t.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
list.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
locale.h
loop_unroll.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
malloc.h Simplify __malloc_initialized 2021-07-22 18:38:04 +05:30
math-narrow-eval.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
math.h Redirect fma calls to __fma in libm 2021-09-15 22:57:35 +00:00
mcheck.h mcheck: Wean away from malloc hooks [BZ #23489] 2021-07-22 18:38:02 +05:30
memory.h
mntent.h Hide internal __hasmntopt function [BZ #18822] 2017-10-01 17:37:42 -07:00
monetary.h Rename __LONG_DOUBLE_USES_FLOAT128 to __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI 2020-04-30 08:52:08 -05:00
mqueue.h Linux: Move mq_send, mq_timedsend, __mq_timedsend_time64 to libc 2021-06-25 12:21:12 +02:00
netdb.h Move 'netgroup' routines from 'inet' into 'nss' 2023-10-24 12:30:59 +02:00
netgroup.h Move 'netgroup' routines from 'inet' into 'nss' 2023-10-24 12:30:59 +02:00
nl_types.h
nss_dns.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
nss_files.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
nss.h nss: Export nscd hash function as __nss_hash [BZ #22459] 2017-11-23 14:08:11 +01:00
nsswitch.h
obstack.h
plural-exp.h Hide internal __gettextparse function [BZ #18822] 2017-10-01 17:31:05 -07:00
poll.h
printf_buffer.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
printf.h stdio-common: Convert vfprintf and related functions to buffers 2022-12-19 18:56:54 +01:00
pthread.h Linux: Move mq_notify from librt to libc 2021-06-25 12:20:47 +02:00
pty.h login: Move libutil into libc 2021-06-30 08:43:37 +02:00
pwd.h Remove 'pwd' and merge into 'nss' 2023-10-24 12:30:59 +02:00
random-bits.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
re_comp.h Add missing header wrappers under include/ 2019-02-16 08:25:16 +01:00
regex.h Fix regex type usage 2023-05-01 09:08:59 -04:00
regexp.h Add missing header wrappers under include/ 2019-02-16 08:25:16 +01:00
register-atfork.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
resolv.h resolv: Add internal __res_binary_hnok function 2022-08-30 10:02:49 +02:00
rounding-mode.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
rtld-malloc.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
sched.h Add hidden prototypes for __sched_getparam, __sched_getscheduler 2020-02-20 08:57:01 +01:00
scratch_buffer.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
search.h misc: Add twalk_r function 2019-05-02 11:42:51 +02:00
set-freeres.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
setjmp.h chk: Add and fix hidden builtin definitions for *_chk 2023-08-03 22:46:48 +02:00
sgtty.h
shadow.h Remove 'shadow' and merge into 'nss' 2023-10-24 12:30:59 +02:00
shlib-compat.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
shm-directory.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
signal.h stdio: Remove the usage of $(fno-unit-at-a-time) for siglist.c 2022-05-13 10:54:41 -03:00
spawn.h posix: Use posix_spawn for wordexp 2019-10-09 17:48:41 -03:00
stab.h
stackinfo.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
stap-probe.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
stdbit.h Implement C23 <stdbit.h> 2024-01-03 12:07:14 +00:00
stdc-predef.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
stdint.h Move inttypes.h and stdint.h to stdlib. 2019-03-13 09:42:09 -04:00
stdio_ext.h
stdio.h posix: Sync tempname with gnulib 2024-04-10 14:53:39 -03:00
stdlib.h stdlib: Make abort/_Exit AS-safe (BZ 26275) 2024-10-08 14:40:12 -03:00
string.h string: Add hidden builtin definition for __strcpy_chk. 2024-02-06 09:17:04 +01:00
strings.h
struct___timeb64.h time: Add 64-bit time_t support for ftime 2020-10-27 09:54:50 -03:00
struct___timespec64.h y2038: include: Move struct __timespec64 definition to a separate file 2020-04-06 23:05:11 +02:00
struct___timeval64.h y2038: include: Move struct __timeval64 definition to a separate file 2020-05-05 19:36:25 +02:00
stubs-prologue.h
syscall.h
sysexits.h
syslog.h
tar.h
termios.h Hide internal __tcgetattr function [BZ #18822] 2017-10-01 17:48:24 -07:00
tgmath.h
time.h Define in_int32_t_range to check if the 64 bit time_t syscall should be used 2022-11-17 14:35:13 -03:00
ttyent.h
uchar.h
ucontext.h
ulimit.h
unistd_ext.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
unistd.h unistd: Avoid PLT entries with _FORTIFY_SOURCE 2023-07-05 16:59:48 +02:00
utime.h
utmp.h login: Move libutil into libc 2021-06-30 08:43:37 +02:00
values.h Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
verify.h posix: Sync regex with gnulib 2019-11-06 09:20:52 -03:00
wait.h Add missing header wrappers under include/ 2019-02-16 08:25:16 +01:00
wchar.h Refer to C23 in place of C2X in glibc 2024-02-01 11:02:01 +00:00
wctype.h
wordexp.h