[v6,5/5] posix: Add posix_spawn_file_actions_closefrom_np

Message ID 20210623185115.395812-6-adhemerval.zanella@linaro.org
State Superseded
Headers
Series Add close_range, closefrom, and posix_spawn_file_actions_closefrom_np |

Checks

Context Check Description
dj/TryBot-apply_patch success Patch applied to master at the time it was sent

Commit Message

Adhemerval Zanella June 23, 2021, 6:51 p.m. UTC
  This patch adds a way to close a range of file descriptors on
posix_spawn as a new file action.  The API is similar to the one
provided by Solaris 11 [1], where the file action causes the all open
file descriptors greater than or equal to input on to be closed when
the new process is spawned.

The function posix_spawn_file_actions_closefrom_np is safe to be
implemented by iterating over /proc/self/fd, since the Linux spawni.c
helper process does not use CLONE_FILES, so its has own file descriptor
table and any failure (in /proc operation) aborts the process creation
and returns an error to the caller.

I am aware that this file action might be redundant to the current
approach of POSIX in promoting O_CLOEXEC in more interfaces. However
O_CLOEXEC is still not the default and for some specific usages, the
caller needs to close all possible file descriptors to avoid them
leaking.  Some examples are CPython (discussed in BZ#10353) and OpenJDK
jspawnhelper [2] (where OpenJDK spawns a helper process to exactly
closes all file descriptors).  Most likely any environment which calls
functions that might open file descriptor under the hood and aim to use
posix_spawn might face the same requirement.

Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc64le-linux-gnu, and
aarch64-linux-gnu.

[1] https://docs.oracle.com/cd/E36784_01/html/E36874/posix-spawn-file-actions-addclosefrom-np-3c.html
[2] https://github.com/openjdk/jdk/blob/master/src/java.base/unix/native/libjava/childproc.c#L82
---
 NEWS                                          |   5 +
 include/unistd.h                              |   2 +-
 posix/Makefile                                |   4 +-
 posix/Versions                                |   1 +
 posix/spawn.h                                 |   8 +
 posix/spawn_faction_addclosefrom.c            |  57 ++++
 posix/spawn_faction_destroy.c                 |   1 +
 posix/spawn_int.h                             |   6 +
 posix/tst-spawn5.c                            | 284 ++++++++++++++++++
 sysdeps/generic/spawn_int_def.h               |  24 ++
 sysdeps/mach/hurd/i386/libc.abilist           |   1 +
 sysdeps/mach/hurd/spawni.c                    |   4 +
 sysdeps/posix/spawni.c                        |   4 +
 sysdeps/unix/sysv/linux/aarch64/libc.abilist  |   1 +
 sysdeps/unix/sysv/linux/alpha/libc.abilist    |   1 +
 sysdeps/unix/sysv/linux/arc/libc.abilist      |   1 +
 sysdeps/unix/sysv/linux/arm/be/libc.abilist   |   1 +
 sysdeps/unix/sysv/linux/arm/le/libc.abilist   |   1 +
 sysdeps/unix/sysv/linux/closefrom.c           |   3 +-
 sysdeps/unix/sysv/linux/closefrom_fallback.c  |   8 +-
 sysdeps/unix/sysv/linux/csky/libc.abilist     |   1 +
 sysdeps/unix/sysv/linux/hppa/libc.abilist     |   1 +
 sysdeps/unix/sysv/linux/i386/libc.abilist     |   1 +
 sysdeps/unix/sysv/linux/ia64/libc.abilist     |   1 +
 .../sysv/linux/m68k/coldfire/libc.abilist     |   1 +
 .../unix/sysv/linux/m68k/m680x0/libc.abilist  |   1 +
 .../sysv/linux/microblaze/be/libc.abilist     |   1 +
 .../sysv/linux/microblaze/le/libc.abilist     |   1 +
 .../sysv/linux/mips/mips32/fpu/libc.abilist   |   1 +
 .../sysv/linux/mips/mips32/nofpu/libc.abilist |   1 +
 .../sysv/linux/mips/mips64/n32/libc.abilist   |   1 +
 .../sysv/linux/mips/mips64/n64/libc.abilist   |   1 +
 sysdeps/unix/sysv/linux/nios2/libc.abilist    |   1 +
 .../linux/powerpc/powerpc32/fpu/libc.abilist  |   1 +
 .../powerpc/powerpc32/nofpu/libc.abilist      |   1 +
 .../linux/powerpc/powerpc64/be/libc.abilist   |   1 +
 .../linux/powerpc/powerpc64/le/libc.abilist   |   1 +
 .../unix/sysv/linux/riscv/rv32/libc.abilist   |   1 +
 .../unix/sysv/linux/riscv/rv64/libc.abilist   |   1 +
 .../unix/sysv/linux/s390/s390-32/libc.abilist |   1 +
 .../unix/sysv/linux/s390/s390-64/libc.abilist |   1 +
 sysdeps/unix/sysv/linux/sh/be/libc.abilist    |   1 +
 sysdeps/unix/sysv/linux/sh/le/libc.abilist    |   1 +
 .../sysv/linux/sparc/sparc32/libc.abilist     |   1 +
 .../sysv/linux/sparc/sparc64/libc.abilist     |   1 +
 sysdeps/unix/sysv/linux/spawn_int_def.h       |  25 ++
 sysdeps/unix/sysv/linux/spawni.c              |  34 ++-
 .../unix/sysv/linux/x86_64/64/libc.abilist    |   1 +
 .../unix/sysv/linux/x86_64/x32/libc.abilist   |   1 +
 49 files changed, 482 insertions(+), 21 deletions(-)
 create mode 100644 posix/spawn_faction_addclosefrom.c
 create mode 100644 posix/tst-spawn5.c
 create mode 100644 sysdeps/generic/spawn_int_def.h
 create mode 100644 sysdeps/unix/sysv/linux/spawn_int_def.h
  

Patch

diff --git a/NEWS b/NEWS
index 031898d425..47fe062ed0 100644
--- a/NEWS
+++ b/NEWS
@@ -54,6 +54,11 @@  Major new features:
   greater than given integer.  This function is a GNU extension, although it
   also present in other systems.
 
+* The posix_spawn_file_actions_closefrom_np function has been added, enabling
+  posix_spawn and posix_spawnp to close all file descriptors great than or
+  equal to a giver integer.  This function is a GNU extension, although
+  Solaris also provides a similar function.
+
 Deprecated and removed features, and other changes affecting compatibility:
 
 * The function pthread_mutex_consistent_np has been deprecated; programs
diff --git a/include/unistd.h b/include/unistd.h
index 12044a8531..8bcf164f46 100644
--- a/include/unistd.h
+++ b/include/unistd.h
@@ -156,7 +156,7 @@  extern int __brk (void *__addr) attribute_hidden;
 extern int __close (int __fd);
 libc_hidden_proto (__close)
 extern int __libc_close (int __fd);
-extern _Bool __closefrom_fallback (int __lowfd) attribute_hidden;
+extern _Bool __closefrom_fallback (int __lowfd, _Bool) attribute_hidden;
 extern ssize_t __read (int __fd, void *__buf, size_t __nbytes);
 libc_hidden_proto (__read)
 extern ssize_t __write (int __fd, const void *__buf, size_t __n);
diff --git a/posix/Makefile b/posix/Makefile
index 8d139e54f6..50d17d19de 100644
--- a/posix/Makefile
+++ b/posix/Makefile
@@ -57,6 +57,7 @@  routines :=								      \
 	spawn_faction_init spawn_faction_destroy spawn_faction_addclose	      \
 	spawn_faction_addopen spawn_faction_adddup2 spawn_valid_fd	      \
 	spawn_faction_addchdir spawn_faction_addfchdir			      \
+	spawn_faction_addclosefrom					      \
 	spawnattr_init spawnattr_destroy				      \
 	spawnattr_getdefault spawnattr_setdefault			      \
 	spawnattr_getflags spawnattr_setflags				      \
@@ -106,7 +107,7 @@  tests		:= test-errno tstgetopt testfnm runtests runptests \
 		   tst-sysconf-empty-chroot tst-glob_symlinks tst-fexecve \
 		   tst-glob-tilde test-ssize-max tst-spawn4 bug-regex37 \
 		   bug-regex38 tst-regcomp-truncated tst-spawn-chdir \
-		   tst-wordexp-nocmd tst-execveat
+		   tst-wordexp-nocmd tst-execveat tst-spawn5
 
 # Test for the glob symbol version that was replaced in glibc 2.27.
 ifeq ($(have-GLIBC_2.26)$(build-shared),yesyes)
@@ -275,6 +276,7 @@  tst-exec-static-ARGS = $(tst-exec-ARGS)
 tst-execvpe5-ARGS = -- $(host-test-program-cmd)
 tst-spawn-ARGS = -- $(host-test-program-cmd)
 tst-spawn-static-ARGS = $(tst-spawn-ARGS)
+tst-spawn5-ARGS = -- $(host-test-program-cmd)
 tst-dir-ARGS = `pwd` `cd $(common-objdir)/$(subdir); pwd` `cd $(common-objdir); pwd` $(objpfx)tst-dir
 tst-chmod-ARGS = $(objdir)
 tst-vfork3-ARGS = --test-dir=$(objpfx)
diff --git a/posix/Versions b/posix/Versions
index 5983144d01..f36756b832 100644
--- a/posix/Versions
+++ b/posix/Versions
@@ -153,6 +153,7 @@  libc {
   }
   GLIBC_2.34 {
     execveat;
+    posix_spawn_file_actions_addclosefrom_np;
   }
   GLIBC_PRIVATE {
     __libc_fork; __libc_pread; __libc_pwrite;
diff --git a/posix/spawn.h b/posix/spawn.h
index a29da028cc..990d8a6ba2 100644
--- a/posix/spawn.h
+++ b/posix/spawn.h
@@ -213,6 +213,14 @@  extern int posix_spawn_file_actions_addchdir_np (posix_spawn_file_actions_t *
 extern int posix_spawn_file_actions_addfchdir_np (posix_spawn_file_actions_t *,
 						  int __fd)
      __THROW __nonnull ((1));
+
+/* Add an action to close all file descriptor greater than or equal to FROM
+   during spawn.  This affects the subsequent file actions.  */
+extern int
+posix_spawn_file_actions_addclosefrom_np (posix_spawn_file_actions_t *,
+					  int __from)
+     __THROW __nonnull ((1));
+
 #endif
 
 __END_DECLS
diff --git a/posix/spawn_faction_addclosefrom.c b/posix/spawn_faction_addclosefrom.c
new file mode 100644
index 0000000000..ff35b0519b
--- /dev/null
+++ b/posix/spawn_faction_addclosefrom.c
@@ -0,0 +1,57 @@ 
+/* Add a closefrom to a file action list for posix_spawn.
+   Copyright (C) 2021 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <spawn.h>
+#include <unistd.h>
+#include <spawn_int.h>
+
+int
+__posix_spawn_file_actions_addclosefrom (posix_spawn_file_actions_t
+					 *file_actions, int from)
+{
+#if __SPAWN_SUPPORT_CLOSEFROM
+  struct __spawn_action *rec;
+
+  if (!__spawn_valid_fd (from))
+    return EBADF;
+
+  /* Allocate more memory if needed.  */
+  if (file_actions->__used == file_actions->__allocated
+      && __posix_spawn_file_actions_realloc (file_actions) != 0)
+    /* This can only mean we ran out of memory.  */
+    return ENOMEM;
+
+  /* Add the new value.  */
+  rec = &file_actions->__actions[file_actions->__used];
+  rec->tag = spawn_do_closefrom;
+  rec->action.closefrom_action.from = from;
+
+  /* Account for the new entry.  */
+  ++file_actions->__used;
+
+  return 0;
+#else
+  return EINVAL;
+#endif
+}
+weak_alias (__posix_spawn_file_actions_addclosefrom,
+	    posix_spawn_file_actions_addclosefrom_np)
+#if !__SPAWN_SUPPORT_CLOSEFROM
+stub_warning (posix_spawn_file_actions_addclosefrom_np)
+#endif
diff --git a/posix/spawn_faction_destroy.c b/posix/spawn_faction_destroy.c
index 7776f1a462..1a01b8e80e 100644
--- a/posix/spawn_faction_destroy.c
+++ b/posix/spawn_faction_destroy.c
@@ -39,6 +39,7 @@  __posix_spawn_file_actions_destroy (posix_spawn_file_actions_t *file_actions)
 	case spawn_do_close:
 	case spawn_do_dup2:
 	case spawn_do_fchdir:
+	case spawn_do_closefrom:
 	  /* No cleanup required.  */
 	  break;
 	}
diff --git a/posix/spawn_int.h b/posix/spawn_int.h
index c579cb981d..81d43f2fa3 100644
--- a/posix/spawn_int.h
+++ b/posix/spawn_int.h
@@ -20,6 +20,7 @@ 
 #define _SPAWN_INT_H
 
 #include <spawn.h>
+#include <spawn_int_def.h>
 #include <stdbool.h>
 
 /* Data structure to contain the action information.  */
@@ -32,6 +33,7 @@  struct __spawn_action
     spawn_do_open,
     spawn_do_chdir,
     spawn_do_fchdir,
+    spawn_do_closefrom,
   } tag;
 
   union
@@ -60,6 +62,10 @@  struct __spawn_action
     {
       int fd;
     } fchdir_action;
+    struct
+    {
+      int from;
+    } closefrom_action;
   } action;
 };
 
diff --git a/posix/tst-spawn5.c b/posix/tst-spawn5.c
new file mode 100644
index 0000000000..1e67d071b4
--- /dev/null
+++ b/posix/tst-spawn5.c
@@ -0,0 +1,284 @@ 
+/* Tests for posix_spawn signal handling.
+   Copyright (C) 2021 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include <spawn.h>
+#include <fcntl.h>
+#include <sys/wait.h>
+#include <dirent.h>
+#include <stdbool.h>
+#include <errno.h>
+#include <limits.h>
+
+#include <support/check.h>
+#include <support/xunistd.h>
+#include <support/support.h>
+
+#include <arch-fd_to_filename.h>
+#include <array_length.h>
+
+/* Nonzero if the program gets called via `exec'.  */
+static int restart;
+
+/* Hold the four initial argument used to respawn the process, plus
+   the extra '--direct' and '--restart', and a final NULL.  */
+static char *initial_argv[7];
+
+#define CMDLINE_OPTIONS \
+  { "restart", no_argument, &restart, 1 },
+
+#define NFDS 100
+
+static int
+open_multiple_temp_files (void)
+{
+  /* Check if the temporary file descriptor has no no gaps.  */
+  int lowfd = xopen ("/dev/null", O_RDONLY, 0600);
+  for (int i = 1; i <= NFDS; i++)
+    TEST_COMPARE (xopen ("/dev/null", O_RDONLY, 0600),
+		  lowfd + i);
+  return lowfd;
+}
+
+/* Called on process re-execution.  The arguments are the expected opened
+   file descriptors.  */
+_Noreturn static void
+handle_restart (int argc, char *argv[])
+{
+  size_t nfds = argc > 1 ? argc - 1 : 0;
+  struct fd_t
+  {
+    int fd;
+    _Bool found;
+  } *fds = xmalloc (sizeof (struct fd_t) * nfds);
+  for (int i = 0; i < nfds; i++)
+    {
+      char *endptr;
+      long unsigned int fd = strtoul (argv[i+1], &endptr, 10);
+      if (*endptr != '\0' || fd > INT_MAX)
+        FAIL_EXIT1 ("readdir: invalid file descriptor value: %s", argv[i]);
+
+      fds[i].fd = fd;
+      fds[i].found = false;
+    }
+
+  DIR *dirp = opendir (FD_TO_FILENAME_PREFIX);
+  if (dirp == NULL)
+    FAIL_EXIT1 ("opendir (\"" FD_TO_FILENAME_PREFIX "\"): %m");
+
+  while (true)
+    {
+      errno = 0;
+      struct dirent64 *e = readdir64 (dirp);
+      if (e == NULL)
+        {
+          if (errno != 0)
+            FAIL_EXIT1 ("readdir: %m");
+          break;
+        }
+
+      if (e->d_name[0] == '.')
+        continue;
+
+      char *endptr;
+      long int fd = strtol (e->d_name, &endptr, 10);
+      if (*endptr != '\0' || fd < 0 || fd > INT_MAX)
+        FAIL_EXIT1 ("readdir: invalid file descriptor name: /proc/self/fd/%s",
+                    e->d_name);
+
+      /* Skip the descriptor which is used to enumerate the descriptors.  */
+      if (fd == dirfd (dirp)
+          || fd == STDIN_FILENO
+	  || fd == STDOUT_FILENO
+	  || fd == STDERR_FILENO)
+        continue;
+
+      bool found = false;
+      for (int i = 0; i < nfds; i++)
+	if (fds[i].fd == fd)
+	  fds[i].found = found = true;
+
+      if (!found)
+        FAIL_EXIT1 ("unexpected open file descriptor: %ld", fd);
+    }
+  closedir (dirp);
+
+  for (int i = 0; i < nfds; i++)
+    if (!fds[i].found)
+      FAIL_EXIT1 ("file descriptor %d not opened", fds[i].fd);
+
+  free (fds);
+
+  exit (EXIT_SUCCESS);
+}
+
+static void
+spawn_closefrom_test (posix_spawn_file_actions_t *fa, int lowfd, int highfd,
+		      int *extrafds, size_t nextrafds)
+{
+  /* 6 elements from initial_argv (path to ld.so, '--library-path', the
+     path', application name', '--direct', and '--restart'), up to
+     2 * maximum_fd arguments (the expected open file descriptors), plus
+     NULL.  */
+  enum { argv_size = array_length (initial_argv) + 2 * NFDS + 1 };
+  char *args[argv_size];
+  int argc = 0;
+
+  for (char **arg = initial_argv; *arg != NULL; arg++)
+    args[argc++] = *arg;
+
+  for (int i = lowfd; i < highfd; i++)
+    args[argc++] = xasprintf ("%d", i);
+
+  for (int i = 0; i < nextrafds; i++)
+    args[argc++] = xasprintf ("%d", extrafds[i]);
+
+  args[argc] = NULL;
+  TEST_VERIFY (argc < argv_size);
+
+  pid_t pid;
+  int status;
+
+  TEST_COMPARE (posix_spawn (&pid, args[0], fa, NULL, args, environ), 0);
+  TEST_COMPARE (xwaitpid (pid, &status, 0), pid);
+  TEST_VERIFY (WIFEXITED (status));
+  TEST_VERIFY (!WIFSIGNALED (status));
+  TEST_COMPARE (WEXITSTATUS (status), 0);
+}
+
+static void
+do_test_closefrom (void)
+{
+  int lowfd = open_multiple_temp_files ();
+  const int half_fd = lowfd + NFDS / 2;
+
+  /* Close half of the descriptors and check result.  */
+  {
+    posix_spawn_file_actions_t fa;
+    TEST_COMPARE (posix_spawn_file_actions_init (&fa), 0);
+
+    int ret = posix_spawn_file_actions_addclosefrom_np (&fa, half_fd);
+    if (ret == EINVAL)
+      /* Hurd currently does not support closefrom fileaction.  */
+      FAIL_UNSUPPORTED ("posix_spawn_file_actions_addclosefrom_np unsupported");
+    TEST_COMPARE (ret, 0);
+
+    spawn_closefrom_test (&fa, lowfd, half_fd, NULL, 0);
+
+    TEST_COMPARE (posix_spawn_file_actions_destroy (&fa), 0);
+  }
+
+  /* Create some gaps, close up to a threshold, and check result.  */
+  xclose (lowfd + 57);
+  xclose (lowfd + 78);
+  xclose (lowfd + 81);
+  xclose (lowfd + 82);
+  xclose (lowfd + 84);
+  xclose (lowfd + 90);
+
+  {
+    posix_spawn_file_actions_t fa;
+    TEST_COMPARE (posix_spawn_file_actions_init (&fa), 0);
+
+    TEST_COMPARE (posix_spawn_file_actions_addclosefrom_np (&fa, half_fd), 0);
+
+    spawn_closefrom_test (&fa, lowfd, half_fd, NULL, 0);
+
+    TEST_COMPARE (posix_spawn_file_actions_destroy (&fa), 0);
+  }
+
+  /* Close the remaining but the last one.  */
+  {
+    posix_spawn_file_actions_t fa;
+    TEST_COMPARE (posix_spawn_file_actions_init (&fa), 0);
+
+    TEST_COMPARE (posix_spawn_file_actions_addclosefrom_np (&fa, lowfd + 1), 0);
+
+    spawn_closefrom_test (&fa, lowfd, lowfd + 1, NULL, 0);
+
+    TEST_COMPARE (posix_spawn_file_actions_destroy (&fa), 0);
+  }
+
+  /* Close everything.  */
+  {
+    posix_spawn_file_actions_t fa;
+    TEST_COMPARE (posix_spawn_file_actions_init (&fa), 0);
+
+    TEST_COMPARE (posix_spawn_file_actions_addclosefrom_np (&fa, lowfd), 0);
+
+    spawn_closefrom_test (&fa, lowfd, lowfd, NULL, 0);
+
+    TEST_COMPARE (posix_spawn_file_actions_destroy (&fa), 0);
+  }
+
+  /* Close a range and add some file actions.  */
+  {
+    posix_spawn_file_actions_t fa;
+    TEST_COMPARE (posix_spawn_file_actions_init (&fa), 0);
+
+    TEST_COMPARE (posix_spawn_file_actions_addclosefrom_np (&fa, lowfd + 1), 0);
+    TEST_COMPARE (posix_spawn_file_actions_addopen (&fa, lowfd, "/dev/null",
+						    0666, O_RDONLY), 0);
+    TEST_COMPARE (posix_spawn_file_actions_adddup2 (&fa, lowfd, lowfd + 1), 0);
+    TEST_COMPARE (posix_spawn_file_actions_addopen (&fa, lowfd, "/dev/null",
+						    0666, O_RDONLY), 0);
+
+    spawn_closefrom_test (&fa, lowfd, lowfd, (int[]){lowfd, lowfd + 1}, 2);
+
+    TEST_COMPARE (posix_spawn_file_actions_destroy (&fa), 0);
+  }
+}
+
+static int
+do_test (int argc, char *argv[])
+{
+  /* We must have either:
+
+     - one or four parameters if called initially:
+       + argv[1]: path for ld.so        optional
+       + argv[2]: "--library-path"      optional
+       + argv[3]: the library path      optional
+       + argv[4]: the application name
+
+     - six parameters left if called through re-execution:
+       + argv[1]: the application name
+       + argv[2]: first expected open file descriptor
+       + argv[n]: last expected open file descritptor
+
+     * When built with --enable-hardcoded-path-in-tests or issued without
+       using the loader directly.  */
+
+  if (restart)
+    handle_restart (argc, argv);
+
+  initial_argv[0] = argv[1]; /* path for ld.so  */
+  initial_argv[1] = argv[2]; /* "--library-path"  */
+  initial_argv[2] = argv[3]; /* the library path  */
+  initial_argv[3] = argv[4]; /* the application name  */
+  initial_argv[4] = (char *) "--direct";
+  initial_argv[5] = (char *) "--restart";
+
+  do_test_closefrom ();
+
+  return 0;
+}
+
+#define TEST_FUNCTION_ARGV do_test
+#include <support/test-driver.c>
diff --git a/sysdeps/generic/spawn_int_def.h b/sysdeps/generic/spawn_int_def.h
new file mode 100644
index 0000000000..ef6e03b1ef
--- /dev/null
+++ b/sysdeps/generic/spawn_int_def.h
@@ -0,0 +1,24 @@ 
+/* Internal definitions for posix_spawn functionality.  Generic version.
+   Copyright (C) 2021 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
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _SPAWN_INT_DEF_H
+#define _SPAWN_INT_DEF_H
+
+#define __SPAWN_SUPPORT_CLOSEFROM 0
+
+#endif /* _SPAWN_INT_H */
diff --git a/sysdeps/mach/hurd/i386/libc.abilist b/sysdeps/mach/hurd/i386/libc.abilist
index 76d9e150f2..82c106e181 100644
--- a/sysdeps/mach/hurd/i386/libc.abilist
+++ b/sysdeps/mach/hurd/i386/libc.abilist
@@ -2229,6 +2229,7 @@  GLIBC_2.34 dlopen F
 GLIBC_2.34 dlsym F
 GLIBC_2.34 dlvsym F
 GLIBC_2.34 execveat F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 shm_open F
 GLIBC_2.34 shm_unlink F
 GLIBC_2.34 timespec_getres F
diff --git a/sysdeps/mach/hurd/spawni.c b/sysdeps/mach/hurd/spawni.c
index b5c92365f2..e011c3b34b 100644
--- a/sysdeps/mach/hurd/spawni.c
+++ b/sysdeps/mach/hurd/spawni.c
@@ -613,6 +613,10 @@  retry:
 	  case spawn_do_fchdir:
 	    err = child_fchdir (action->action.fchdir_action.fd);
 	    break;
+
+	  case spawn_do_closefrom:
+	    err = EINVAL;
+	    break;
 	  }
 
 	if (err)
diff --git a/sysdeps/posix/spawni.c b/sysdeps/posix/spawni.c
index fe3b5bb7f6..ad1858fe4e 100644
--- a/sysdeps/posix/spawni.c
+++ b/sysdeps/posix/spawni.c
@@ -231,6 +231,10 @@  __spawni_child (void *arguments)
 	      if (__fchdir (action->action.fchdir_action.fd) != 0)
 		goto fail;
 	      break;
+
+	    case spawn_do_closefrom:
+	      __set_errno (EINVAL);
+	      goto fail;
 	    }
 	}
     }
diff --git a/sysdeps/unix/sysv/linux/aarch64/libc.abilist b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
index e5ec01277d..4460b4078d 100644
--- a/sysdeps/unix/sysv/linux/aarch64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
@@ -2373,6 +2373,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/alpha/libc.abilist b/sysdeps/unix/sysv/linux/alpha/libc.abilist
index 19f7a7fca4..71c5b11f62 100644
--- a/sysdeps/unix/sysv/linux/alpha/libc.abilist
+++ b/sysdeps/unix/sysv/linux/alpha/libc.abilist
@@ -2466,6 +2466,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/arc/libc.abilist b/sysdeps/unix/sysv/linux/arc/libc.abilist
index ce6c13989a..ec81c56141 100644
--- a/sysdeps/unix/sysv/linux/arc/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arc/libc.abilist
@@ -2132,6 +2132,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/arm/be/libc.abilist b/sysdeps/unix/sysv/linux/arm/be/libc.abilist
index 57e8456a3c..59256ad003 100644
--- a/sysdeps/unix/sysv/linux/arm/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arm/be/libc.abilist
@@ -303,6 +303,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/arm/le/libc.abilist b/sysdeps/unix/sysv/linux/arm/le/libc.abilist
index de42eccbba..d6f1607726 100644
--- a/sysdeps/unix/sysv/linux/arm/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arm/le/libc.abilist
@@ -300,6 +300,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/closefrom.c b/sysdeps/unix/sysv/linux/closefrom.c
index f5d7342c2c..372896b775 100644
--- a/sysdeps/unix/sysv/linux/closefrom.c
+++ b/sysdeps/unix/sysv/linux/closefrom.c
@@ -16,6 +16,7 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
+#include <stdbool.h>
 #include <stdio.h>
 #include <sys/param.h>
 #include <unistd.h>
@@ -29,7 +30,7 @@  __closefrom (int lowfd)
   if (r == 0)
     return;
 
-  if (!__closefrom_fallback (l))
+  if (!__closefrom_fallback (l, true))
     __fortify_fail ("closefrom failed to close a file descriptor");
 }
 weak_alias (__closefrom, closefrom)
diff --git a/sysdeps/unix/sysv/linux/closefrom_fallback.c b/sysdeps/unix/sysv/linux/closefrom_fallback.c
index 61e71d388d..9cca55653a 100644
--- a/sysdeps/unix/sysv/linux/closefrom_fallback.c
+++ b/sysdeps/unix/sysv/linux/closefrom_fallback.c
@@ -22,9 +22,11 @@ 
 #include <stdbool.h>
 
 /* Fallback code: iterates over /proc/self/fd, closing each file descriptor
-   that fall on the criteria.  */
+   that fall on the criteria.  If DIRFD_FALLBACK is set, a failure on
+   /proc/self/fd open will trigger a fallback that tries to close a file
+   descriptor before proceed.  */
 _Bool
-__closefrom_fallback (int from)
+__closefrom_fallback (int from, _Bool dirfd_fallback)
 {
   bool ret = false;
 
@@ -33,7 +35,7 @@  __closefrom_fallback (int from)
   if (dirfd == -1)
     {
       /* The closefrom should work even when process can't open new files.  */
-      if (errno == ENOENT)
+      if (errno == ENOENT || !dirfd_fallback)
         goto err;
 
       for (int i = from; i < INT_MAX; i++)
diff --git a/sysdeps/unix/sysv/linux/csky/libc.abilist b/sysdeps/unix/sysv/linux/csky/libc.abilist
index f95d5ebbeb..fc7fff8fd5 100644
--- a/sysdeps/unix/sysv/linux/csky/libc.abilist
+++ b/sysdeps/unix/sysv/linux/csky/libc.abilist
@@ -2392,6 +2392,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/hppa/libc.abilist b/sysdeps/unix/sysv/linux/hppa/libc.abilist
index a9d7fb1a93..53a23e390a 100644
--- a/sysdeps/unix/sysv/linux/hppa/libc.abilist
+++ b/sysdeps/unix/sysv/linux/hppa/libc.abilist
@@ -2346,6 +2346,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/i386/libc.abilist b/sysdeps/unix/sysv/linux/i386/libc.abilist
index 1deab899b1..4d80b531b4 100644
--- a/sysdeps/unix/sysv/linux/i386/libc.abilist
+++ b/sysdeps/unix/sysv/linux/i386/libc.abilist
@@ -2530,6 +2530,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/ia64/libc.abilist b/sysdeps/unix/sysv/linux/ia64/libc.abilist
index 13121df7e0..16762122f8 100644
--- a/sysdeps/unix/sysv/linux/ia64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/ia64/libc.abilist
@@ -2306,6 +2306,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
index e4fb78bf8e..0fb6adf535 100644
--- a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
@@ -304,6 +304,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
index b21d6b04af..77d731b270 100644
--- a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
@@ -2473,6 +2473,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
index 7386b5360c..780be90942 100644
--- a/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
@@ -2443,6 +2443,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
index c4c3f18e4d..7f915cfd11 100644
--- a/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
@@ -2440,6 +2440,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
index b500aa4db3..97800b9f09 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
@@ -2438,6 +2438,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
index 8260c3ba4f..7f4291c7c1 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
@@ -2436,6 +2436,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
index b58b8eef2d..126ffc8431 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
@@ -2444,6 +2444,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
index 3f19142fee..6445e7c407 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
@@ -2362,6 +2362,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/nios2/libc.abilist b/sysdeps/unix/sysv/linux/nios2/libc.abilist
index a1d7b0c25f..a573af9d9f 100644
--- a/sysdeps/unix/sysv/linux/nios2/libc.abilist
+++ b/sysdeps/unix/sysv/linux/nios2/libc.abilist
@@ -2482,6 +2482,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
index 1f81867311..842b466b3f 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
@@ -2500,6 +2500,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
index 9f74a84ead..4dc6470c79 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
@@ -2533,6 +2533,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
index 8add515ff4..e5b0b746c1 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
@@ -2270,6 +2270,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
index ab7489200b..412191fcd7 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
@@ -2569,6 +2569,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist b/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
index 273c579b2d..d681b606e7 100644
--- a/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
@@ -2134,6 +2134,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist b/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
index 9ae1c2ea89..053785d06f 100644
--- a/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
@@ -2334,6 +2334,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
index 622d19d754..7837ce9e95 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
@@ -2498,6 +2498,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
index 464e4cefde..78b99b9d25 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
@@ -2307,6 +2307,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/sh/be/libc.abilist b/sysdeps/unix/sysv/linux/sh/be/libc.abilist
index d75a0ec228..655eec6150 100644
--- a/sysdeps/unix/sysv/linux/sh/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sh/be/libc.abilist
@@ -2353,6 +2353,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/sh/le/libc.abilist b/sysdeps/unix/sysv/linux/sh/le/libc.abilist
index 0eaeffda80..114b650965 100644
--- a/sysdeps/unix/sysv/linux/sh/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sh/le/libc.abilist
@@ -2350,6 +2350,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
index 79e3d5a658..d3f3b83398 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
@@ -2491,6 +2491,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
index 727b767863..106a4a3296 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
@@ -2327,6 +2327,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/spawn_int_def.h b/sysdeps/unix/sysv/linux/spawn_int_def.h
new file mode 100644
index 0000000000..3be65b5711
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/spawn_int_def.h
@@ -0,0 +1,25 @@ 
+/* Internal definitions for posix_spawn functionality.  Linux version.
+   Copyright (C) 2021 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
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _SPAWN_INT_DEF_H
+#define _SPAWN_INT_DEF_H
+
+/* spawni.c implements closefrom by interacting over /proc/self/fd.  */
+#define __SPAWN_SUPPORT_CLOSEFROM 1
+
+#endif /* _SPAWN_INT_H */
diff --git a/sysdeps/unix/sysv/linux/spawni.c b/sysdeps/unix/sysv/linux/spawni.c
index 3b435e6c86..403bf609df 100644
--- a/sysdeps/unix/sysv/linux/spawni.c
+++ b/sysdeps/unix/sysv/linux/spawni.c
@@ -16,22 +16,16 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#include <spawn.h>
-#include <fcntl.h>
-#include <paths.h>
-#include <string.h>
-#include <sys/resource.h>
-#include <sys/wait.h>
-#include <sys/param.h>
-#include <sys/mman.h>
-#include <not-cancel.h>
+#include <internal-signals.h>
+#include <ldsodefs.h>
 #include <local-setxid.h>
+#include <not-cancel.h>
+#include <paths.h>
 #include <shlib-compat.h>
-#include <pthreadP.h>
-#include <dl-sysdep.h>
-#include <libc-pointer-arith.h>
-#include <ldsodefs.h>
-#include "spawn_int.h"
+#include <spawn.h>
+#include <spawn_int.h>
+#include <sysdep.h>
+#include <sys/resource.h>
 
 /* The Linux implementation of posix_spawn{p} uses the clone syscall directly
    with CLONE_VM and CLONE_VFORK flags and an allocated stack.  The new stack
@@ -280,6 +274,14 @@  __spawni_child (void *arguments)
 	      if (__fchdir (action->action.fchdir_action.fd) != 0)
 		goto fail;
 	      break;
+
+	    case spawn_do_closefrom:
+	      {
+		int lowfd = action->action.closefrom_action.from;
+	        int r = INLINE_SYSCALL_CALL (close_range, lowfd, ~0U, 0);
+		if (r != 0 && !__closefrom_fallback (lowfd, false))
+		  goto fail;
+	      } break;
 	    }
 	}
     }
@@ -344,7 +346,9 @@  __spawnix (pid_t * pid, const char *file,
   /* We need at least a few pages in case the compiler's stack checking is
      enabled.  In some configs, it is known to use at least 24KiB.  We use
      32KiB to be "safe" from anything the compiler might do.  Besides, the
-     extra pages won't actually be allocated unless they get used.  */
+     extra pages won't actually be allocated unless they get used.
+     It also acts the slack for spawn_closefrom (including MIPS64 getdents64
+     where it might use about 1k extra stack space.  */
   argv_size += (32 * 1024);
   size_t stack_size = ALIGN_UP (argv_size, GLRO(dl_pagesize));
   void *stack = __mmap (NULL, stack_size, prot,
diff --git a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
index fc84da9bae..00e31c04cd 100644
--- a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
@@ -2285,6 +2285,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
index 2c44f71119..ed7e68ed4a 100644
--- a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
@@ -2388,6 +2388,7 @@  GLIBC_2.34 mtx_lock F
 GLIBC_2.34 mtx_timedlock F
 GLIBC_2.34 mtx_trylock F
 GLIBC_2.34 mtx_unlock F
+GLIBC_2.34 posix_spawn_file_actions_addclosefrom_np F
 GLIBC_2.34 pthread_attr_getaffinity_np F
 GLIBC_2.34 pthread_attr_getguardsize F
 GLIBC_2.34 pthread_attr_getstack F