[v7,2/4] linux: Add close_range

Message ID 20210706145839.1658623-3-adhemerval.zanella@linaro.org
State New
Headers show
Series
  • Add close_range, closefrom, and posix_spawn_file_actions_closefrom_np
Related show

Commit Message

Adhemerval Zanella via Libc-alpha July 6, 2021, 2:58 p.m.
Changes from previous version:

  - Fixed manual entry and added ENOSYS returned code.

--

It was added on Linux 5.9 (278a5fbaed89) with CLOSE_RANGE_CLOEXEC
added on 5.11 (582f1fb6b721f).  Although FreeBSD has added the same
syscall, this only adds the symbol on Linux ports.  This syscall is
required to provided a fail-safe way to implement the closefrom
symbol (BZ #10353).

Checked on x86_64-linux-gnu on kernel v5.9 and v5.4.
---
 NEWS                                          |   3 +
 include/bits/unistd_ext.h                     |   6 +
 manual/llio.texi                              |  49 +++
 sysdeps/unix/sysv/linux/Makefile              |   3 +-
 sysdeps/unix/sysv/linux/Versions              |   1 +
 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/bits/unistd_ext.h     |  22 ++
 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/syscalls.list         |   1 +
 sysdeps/unix/sysv/linux/tst-close_range.c     | 303 ++++++++++++++++++
 .../unix/sysv/linux/x86_64/64/libc.abilist    |   1 +
 .../unix/sysv/linux/x86_64/x32/libc.abilist   |   1 +
 40 files changed, 419 insertions(+), 1 deletion(-)
 create mode 100644 include/bits/unistd_ext.h
 create mode 100644 sysdeps/unix/sysv/linux/tst-close_range.c

-- 
2.30.2

Comments

Adhemerval Zanella via Libc-alpha July 7, 2021, 10:22 a.m. | #1
* Adhemerval Zanella via Libc-alpha:


> diff --git a/manual/llio.texi b/manual/llio.texi

> index eafc27120d..ea6d34dd5a 100644

> --- a/manual/llio.texi

> +++ b/manual/llio.texi

> @@ -284,6 +284,55 @@ of trying to close its underlying file descriptor with @code{close}.

>  This flushes any buffered output and updates the stream object to

>  indicate that it is closed.

>  

> +@deftypefun int close_range (unsigned int @var{lowfd}, unsigned int @var{maxfd}, int @var{flags})

> +@standards{Linux, unistd.h}

> +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{@acsfd{}}}

> +@c This is a syscall for Linux v5.9.  There is no fallback emulation for

> +@c older kernels.

> +

> +The function @code{close_range} closes the file descriptor from @var{lowfd}

> +to @var{maxfd} (inclusive).  This function is similar to call @code{close} in

> +specified file descriptor range depending on the @var{flags}.

> +

> +This is function is only supported on recent Linux versions and @theglibc{}

> +does not provide any fallback (the application will need to handle possible

> +@code{ENOSYS}).

> +

> +The @var{flags} add options on how the files are closes.  Linux currently

> +supports:

> +

> +@vtable @code

> +@item CLOSE_RANGE_UNSHARE

> +Unshare the file descriptor table before closing file descriptors.

> +

> +@item CLOSE_RANGE_CLOEXEC

> +Set the @code{FD_CLOEXEC} bit instead of closing the file descriptor.

> +@end vtable

> +

> +The normal return value from @code{close_range} is @math{0}; a value

> +of @math{-1} is returned in case of failure.  The following @code{errno} error

> +conditions are defined for this function:

> +

> +@table @code

> +@item EINVAL

> +The @var{lowfd} value is larger than @var{maxfd} or an unsupported @var{flags}

> +is used.

> +

> +@item ENOMEM

> +Either there is not enough memory for the operation, or the process is

> +out of address space.


I think the address space limitation does not apply here, and this error
can only happen for CLOSE_RANGE_UNSHARE.  This is important information
because plain close cannot fail, either.  No possibility of failure is a
requirement in many cases to use this interface.

> +@item EMFILE

> +The process has too many files open.

> +The maximum number of file descriptors is controlled by the

> +@code{RLIMIT_NOFILE} resource limit; @pxref{Limits on Resources}.


Can EMFILE (or ENFILE) really happen even with CLOSE_RANGE_UNSHARE?  I
don't think so.

> diff --git a/sysdeps/unix/sysv/linux/bits/unistd_ext.h b/sysdeps/unix/sysv/linux/bits/unistd_ext.h

> index 2e529be577..bf313e8af8 100644

> --- a/sysdeps/unix/sysv/linux/bits/unistd_ext.h

> +++ b/sysdeps/unix/sysv/linux/bits/unistd_ext.h

> @@ -33,4 +33,26 @@

>     not detached and has not been joined.  */

>  extern __pid_t gettid (void) __THROW;

>  

> +#ifdef __has_include

> +# if __has_include ("linux/close_range.h")

> +#  include "linux/close_range.h"

> +# endif

>  #endif

> +/* Unshare the file descriptor table before closing file descriptors.  */

> +#ifndef CLOSE_RANGE_UNSHARE

> +# define CLOSE_RANGE_UNSHARE (1U << 1)

> +#endif

> +/* Set the FD_CLOEXEC bit instead of closing the file descriptor.  */

> +#ifndef CLOSE_RANGE_CLOEXEC

> +# define CLOSE_RANGE_CLOEXEC (1U << 2)

> +#endif

> +

> +/* Close all file descriptors in the range FD up to MAX_FD.  The flag FLAGS

> +   are define by the CLOSE_RANGE prefix.  This function behaves like close

> +   on the range, but in a fail-safe where it will either fail and not close

> +   any file descriptor or close all of them.  Returns 0 on successor or -1

> +   for failure (and sets errno accordingly).  */

> +extern int close_range (unsigned int __fd, unsigned int __max_fd,

> +			int __flags) __THROW;


The fail-safe aspect is not mentioned in the manual.  It's confused
because it's unclear what happens with gaps.

Thanks,
Florian
Adhemerval Zanella via Libc-alpha July 7, 2021, 12:51 p.m. | #2
On 07/07/2021 07:22, Florian Weimer wrote:
> * Adhemerval Zanella via Libc-alpha:

> 

> 

>> diff --git a/manual/llio.texi b/manual/llio.texi

>> index eafc27120d..ea6d34dd5a 100644

>> --- a/manual/llio.texi

>> +++ b/manual/llio.texi

>> @@ -284,6 +284,55 @@ of trying to close its underlying file descriptor with @code{close}.

>>  This flushes any buffered output and updates the stream object to

>>  indicate that it is closed.

>>  

>> +@deftypefun int close_range (unsigned int @var{lowfd}, unsigned int @var{maxfd}, int @var{flags})

>> +@standards{Linux, unistd.h}

>> +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{@acsfd{}}}

>> +@c This is a syscall for Linux v5.9.  There is no fallback emulation for

>> +@c older kernels.

>> +

>> +The function @code{close_range} closes the file descriptor from @var{lowfd}

>> +to @var{maxfd} (inclusive).  This function is similar to call @code{close} in

>> +specified file descriptor range depending on the @var{flags}.

>> +

>> +This is function is only supported on recent Linux versions and @theglibc{}

>> +does not provide any fallback (the application will need to handle possible

>> +@code{ENOSYS}).

>> +

>> +The @var{flags} add options on how the files are closes.  Linux currently

>> +supports:

>> +

>> +@vtable @code

>> +@item CLOSE_RANGE_UNSHARE

>> +Unshare the file descriptor table before closing file descriptors.

>> +

>> +@item CLOSE_RANGE_CLOEXEC

>> +Set the @code{FD_CLOEXEC} bit instead of closing the file descriptor.

>> +@end vtable

>> +

>> +The normal return value from @code{close_range} is @math{0}; a value

>> +of @math{-1} is returned in case of failure.  The following @code{errno} error

>> +conditions are defined for this function:

>> +

>> +@table @code

>> +@item EINVAL

>> +The @var{lowfd} value is larger than @var{maxfd} or an unsupported @var{flags}

>> +is used.

>> +

>> +@item ENOMEM

>> +Either there is not enough memory for the operation, or the process is

>> +out of address space.

> 

> I think the address space limitation does not apply here, and this error

> can only happen for CLOSE_RANGE_UNSHARE.  This is important information

> because plain close cannot fail, either.  No possibility of failure is a

> requirement in many cases to use this interface.


Yes, it seems that only CLOSE_RANGE_UNSHARED code patch (unshare_fd->dup_fd)
does trigger it.  I changed it to:

  @item EMFILE                                                                                                     
  The process has too many files open and it can only happens when                                                 
  @code{CLOSE_RANGE_UNSHARED} is used.                                                                             
  The maximum number of file descriptors is controlled by the                                                      
  @code{RLIMIT_NOFILE} resource limit; @pxref{Limits on Resources}.     

> 

>> +@item EMFILE

>> +The process has too many files open.

>> +The maximum number of file descriptors is controlled by the

>> +@code{RLIMIT_NOFILE} resource limit; @pxref{Limits on Resources}.

> 

> Can EMFILE (or ENFILE) really happen even with CLOSE_RANGE_UNSHARE?  I

> don't think so.


It is what man-pages describes:

  commit e3e22b2b2b50829191e93e05653fc3651171b8dc
  Author: Michael Kerrisk <mtk.manpages@gmail.com>
  Date:   Sun Mar 21 16:32:20 2021 +0100

      close_range.2: Correct the explanation of the EMFILE error
    
      close_range() CLOSE_RANGE_USHARE triggers a call to dup_fd()
      which in turn calls alloc_fdtable(), which checks that
      sysctl_nr_open has not been exceeded.
    
I also have change it to:

 @item ENOMEM                                                                                                     
 Either there is not enough memory for the operation, or the process is                                           
 out of address space.  It can only when @code{CLOSE_RANGE_UNSHARED} is
 used.


> 

>> diff --git a/sysdeps/unix/sysv/linux/bits/unistd_ext.h b/sysdeps/unix/sysv/linux/bits/unistd_ext.h

>> index 2e529be577..bf313e8af8 100644

>> --- a/sysdeps/unix/sysv/linux/bits/unistd_ext.h

>> +++ b/sysdeps/unix/sysv/linux/bits/unistd_ext.h

>> @@ -33,4 +33,26 @@

>>     not detached and has not been joined.  */

>>  extern __pid_t gettid (void) __THROW;

>>  

>> +#ifdef __has_include

>> +# if __has_include ("linux/close_range.h")

>> +#  include "linux/close_range.h"

>> +# endif

>>  #endif

>> +/* Unshare the file descriptor table before closing file descriptors.  */

>> +#ifndef CLOSE_RANGE_UNSHARE

>> +# define CLOSE_RANGE_UNSHARE (1U << 1)

>> +#endif

>> +/* Set the FD_CLOEXEC bit instead of closing the file descriptor.  */

>> +#ifndef CLOSE_RANGE_CLOEXEC

>> +# define CLOSE_RANGE_CLOEXEC (1U << 2)

>> +#endif

>> +

>> +/* Close all file descriptors in the range FD up to MAX_FD.  The flag FLAGS

>> +   are define by the CLOSE_RANGE prefix.  This function behaves like close

>> +   on the range, but in a fail-safe where it will either fail and not close

>> +   any file descriptor or close all of them.  Returns 0 on successor or -1

>> +   for failure (and sets errno accordingly).  */

>> +extern int close_range (unsigned int __fd, unsigned int __max_fd,

>> +			int __flags) __THROW;

> 

> The fail-safe aspect is not mentioned in the manual.  It's confused

> because it's unclear what happens with gaps.


I changed it to the following, since afaiu kernel ignores gaps and our
fallback also ignore close return code.

  /* Close all file descriptors in the range FD up to MAX_FD.  The flag FLAGS
     are define by the CLOSE_RANGE prefix.  This function behaves like close
     on the range, but in a fail-safe where it will either fail and not close
     any file descriptor or close all of them.  Gaps where the file descriptor
     is invalid are ignored.   Returns 0 on successor or -1 for failure (and
     sets errno accordingly).  */
Adhemerval Zanella via Libc-alpha July 7, 2021, 12:53 p.m. | #3
* Adhemerval Zanella:

> I changed it to the following, since afaiu kernel ignores gaps and our

> fallback also ignore close return code.

>

>   /* Close all file descriptors in the range FD up to MAX_FD.  The flag FLAGS

>      are define by the CLOSE_RANGE prefix.  This function behaves like close

>      on the range, but in a fail-safe where it will either fail and not close

>      any file descriptor or close all of them.  Gaps where the file descriptor

>      is invalid are ignored.   Returns 0 on successor or -1 for failure (and

>      sets errno accordingly).  */


Okay, thanks for fine-tuning this.

Florian

Patch

diff --git a/NEWS b/NEWS
index 8e72946c3f..be04b217fe 100644
--- a/NEWS
+++ b/NEWS
@@ -60,6 +60,9 @@  Major new features:
   to call async-signal-safe functions (such as raise or execve).  This function
   is currently a GNU extension.
 
+* On Linux, the close_range function has been added.  It allows efficiently
+  closing a range of file descriptors on recent kernels (version 5.9).
+
 Deprecated and removed features, and other changes affecting compatibility:
 
 * The function pthread_mutex_consistent_np has been deprecated; programs
diff --git a/include/bits/unistd_ext.h b/include/bits/unistd_ext.h
new file mode 100644
index 0000000000..277be05746
--- /dev/null
+++ b/include/bits/unistd_ext.h
@@ -0,0 +1,6 @@ 
+#include_next <bits/unistd_ext.h>
+
+#ifndef _ISOMAC
+extern int __close_range (unsigned int lowfd, unsigned int highfd, int flags);
+libc_hidden_proto (__close_range);
+#endif
diff --git a/manual/llio.texi b/manual/llio.texi
index eafc27120d..ea6d34dd5a 100644
--- a/manual/llio.texi
+++ b/manual/llio.texi
@@ -284,6 +284,55 @@  of trying to close its underlying file descriptor with @code{close}.
 This flushes any buffered output and updates the stream object to
 indicate that it is closed.
 
+@deftypefun int close_range (unsigned int @var{lowfd}, unsigned int @var{maxfd}, int @var{flags})
+@standards{Linux, unistd.h}
+@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{@acsfd{}}}
+@c This is a syscall for Linux v5.9.  There is no fallback emulation for
+@c older kernels.
+
+The function @code{close_range} closes the file descriptor from @var{lowfd}
+to @var{maxfd} (inclusive).  This function is similar to call @code{close} in
+specified file descriptor range depending on the @var{flags}.
+
+This is function is only supported on recent Linux versions and @theglibc{}
+does not provide any fallback (the application will need to handle possible
+@code{ENOSYS}).
+
+The @var{flags} add options on how the files are closes.  Linux currently
+supports:
+
+@vtable @code
+@item CLOSE_RANGE_UNSHARE
+Unshare the file descriptor table before closing file descriptors.
+
+@item CLOSE_RANGE_CLOEXEC
+Set the @code{FD_CLOEXEC} bit instead of closing the file descriptor.
+@end vtable
+
+The normal return value from @code{close_range} is @math{0}; a value
+of @math{-1} is returned in case of failure.  The following @code{errno} error
+conditions are defined for this function:
+
+@table @code
+@item EINVAL
+The @var{lowfd} value is larger than @var{maxfd} or an unsupported @var{flags}
+is used.
+
+@item ENOMEM
+Either there is not enough memory for the operation, or the process is
+out of address space.
+
+@item EMFILE
+The process has too many files open.
+The maximum number of file descriptors is controlled by the
+@code{RLIMIT_NOFILE} resource limit; @pxref{Limits on Resources}.
+
+@item ENOSYS
+The kernel does not implement the required functionality.
+@end table
+@end deftypefun
+
+
 @node I/O Primitives
 @section Input and Output Primitives
 
diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile
index faea02bd1b..e308711168 100644
--- a/sysdeps/unix/sysv/linux/Makefile
+++ b/sysdeps/unix/sysv/linux/Makefile
@@ -116,7 +116,8 @@  tests += tst-clone tst-clone2 tst-clone3 tst-fanotify tst-personality \
 	 tst-tgkill tst-sysvsem-linux tst-sysvmsg-linux tst-sysvshm-linux \
 	 tst-timerfd tst-ppoll \
 	 tst-clock_adjtime tst-adjtimex tst-ntp_adjtime tst-ntp_gettime \
-	 tst-ntp_gettimex tst-sigtimedwait tst-misalign-clone
+	 tst-ntp_gettimex tst-sigtimedwait tst-misalign-clone \
+	 tst-close_range
 
 # Test for the symbol version of fcntl that was replaced in glibc 2.28.
 ifeq ($(have-GLIBC_2.27)$(build-shared),yesyes)
diff --git a/sysdeps/unix/sysv/linux/Versions b/sysdeps/unix/sysv/linux/Versions
index 53cb7b23e2..4884216825 100644
--- a/sysdeps/unix/sysv/linux/Versions
+++ b/sysdeps/unix/sysv/linux/Versions
@@ -283,6 +283,7 @@  libc {
     __wait3_time64;
     __wait4_time64;
 %endif
+    close_range;
   }
   GLIBC_PRIVATE {
     # functions used in other libraries
diff --git a/sysdeps/unix/sysv/linux/aarch64/libc.abilist b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
index 6730cbdd6b..c32f5898fe 100644
--- a/sysdeps/unix/sysv/linux/aarch64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
@@ -2409,6 +2409,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/alpha/libc.abilist b/sysdeps/unix/sysv/linux/alpha/libc.abilist
index 63de4fadc3..cb10eadbb9 100644
--- a/sysdeps/unix/sysv/linux/alpha/libc.abilist
+++ b/sysdeps/unix/sysv/linux/alpha/libc.abilist
@@ -2508,6 +2508,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/arc/libc.abilist b/sysdeps/unix/sysv/linux/arc/libc.abilist
index 2f13701fd7..a697c930e1 100644
--- a/sysdeps/unix/sysv/linux/arc/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arc/libc.abilist
@@ -2168,6 +2168,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/arm/be/libc.abilist b/sysdeps/unix/sysv/linux/arm/be/libc.abilist
index 9b824f1605..7dbe38dcb7 100644
--- a/sysdeps/unix/sysv/linux/arm/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arm/be/libc.abilist
@@ -302,6 +302,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/arm/le/libc.abilist b/sysdeps/unix/sysv/linux/arm/le/libc.abilist
index 443a81b8f7..0ee69506ea 100644
--- a/sysdeps/unix/sysv/linux/arm/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arm/le/libc.abilist
@@ -299,6 +299,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/bits/unistd_ext.h b/sysdeps/unix/sysv/linux/bits/unistd_ext.h
index 2e529be577..bf313e8af8 100644
--- a/sysdeps/unix/sysv/linux/bits/unistd_ext.h
+++ b/sysdeps/unix/sysv/linux/bits/unistd_ext.h
@@ -33,4 +33,26 @@ 
    not detached and has not been joined.  */
 extern __pid_t gettid (void) __THROW;
 
+#ifdef __has_include
+# if __has_include ("linux/close_range.h")
+#  include "linux/close_range.h"
+# endif
 #endif
+/* Unshare the file descriptor table before closing file descriptors.  */
+#ifndef CLOSE_RANGE_UNSHARE
+# define CLOSE_RANGE_UNSHARE (1U << 1)
+#endif
+/* Set the FD_CLOEXEC bit instead of closing the file descriptor.  */
+#ifndef CLOSE_RANGE_CLOEXEC
+# define CLOSE_RANGE_CLOEXEC (1U << 2)
+#endif
+
+/* Close all file descriptors in the range FD up to MAX_FD.  The flag FLAGS
+   are define by the CLOSE_RANGE prefix.  This function behaves like close
+   on the range, but in a fail-safe where it will either fail and not close
+   any file descriptor or close all of them.  Returns 0 on successor or -1
+   for failure (and sets errno accordingly).  */
+extern int close_range (unsigned int __fd, unsigned int __max_fd,
+			int __flags) __THROW;
+
+#endif /* __USE_GNU  */
diff --git a/sysdeps/unix/sysv/linux/csky/libc.abilist b/sysdeps/unix/sysv/linux/csky/libc.abilist
index 243de3cf93..c5849e1da2 100644
--- a/sysdeps/unix/sysv/linux/csky/libc.abilist
+++ b/sysdeps/unix/sysv/linux/csky/libc.abilist
@@ -2434,6 +2434,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/hppa/libc.abilist b/sysdeps/unix/sysv/linux/hppa/libc.abilist
index 24ae58bb6f..9368379d9d 100644
--- a/sysdeps/unix/sysv/linux/hppa/libc.abilist
+++ b/sysdeps/unix/sysv/linux/hppa/libc.abilist
@@ -2387,6 +2387,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/i386/libc.abilist b/sysdeps/unix/sysv/linux/i386/libc.abilist
index 09bebcd5a1..e4a16d0bcf 100644
--- a/sysdeps/unix/sysv/linux/i386/libc.abilist
+++ b/sysdeps/unix/sysv/linux/i386/libc.abilist
@@ -2571,6 +2571,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/ia64/libc.abilist b/sysdeps/unix/sysv/linux/ia64/libc.abilist
index 0bafe09253..f7a29d00de 100644
--- a/sysdeps/unix/sysv/linux/ia64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/ia64/libc.abilist
@@ -2346,6 +2346,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
index c1fcde4c24..7a1b38fe81 100644
--- a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
@@ -303,6 +303,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
index 407651cfd7..64591d99cc 100644
--- a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
@@ -2514,6 +2514,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
index 7da722a734..1769dc5c80 100644
--- a/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
@@ -2485,6 +2485,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
index c374607b81..4373d181fb 100644
--- a/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
@@ -2482,6 +2482,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
index b1f426e053..c714662ff3 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
@@ -2479,6 +2479,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
index 066ceb2258..d6d9f3b5f6 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
@@ -2477,6 +2477,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
index 51c563ebbe..287fc03201 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
@@ -2485,6 +2485,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
index 28db715d8a..92dc711ee2 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
@@ -2397,6 +2397,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/nios2/libc.abilist b/sysdeps/unix/sysv/linux/nios2/libc.abilist
index ab9f2bd42c..b1c4e54a70 100644
--- a/sysdeps/unix/sysv/linux/nios2/libc.abilist
+++ b/sysdeps/unix/sysv/linux/nios2/libc.abilist
@@ -2524,6 +2524,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
index 83f8513e17..1ed9e1c9a7 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
@@ -2541,6 +2541,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
index 0fad357bf6..953e05cc33 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
@@ -2574,6 +2574,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
index 424ec8d953..e6bcab06d5 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
@@ -2310,6 +2310,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
index 9909fd0e9a..525cb85de2 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
@@ -2605,6 +2605,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist b/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
index 7085989b16..a1d89d2f14 100644
--- a/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
@@ -2170,6 +2170,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist b/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
index a855997957..84f7a8561a 100644
--- a/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
@@ -2370,6 +2370,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
index 12aeb82520..edd1dbbbdb 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
@@ -2539,6 +2539,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
index e2d746ad5f..19160f33ba 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
@@ -2347,6 +2347,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/sh/be/libc.abilist b/sysdeps/unix/sysv/linux/sh/be/libc.abilist
index 1ce4b54bf2..8e99b18060 100644
--- a/sysdeps/unix/sysv/linux/sh/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sh/be/libc.abilist
@@ -2394,6 +2394,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/sh/le/libc.abilist b/sysdeps/unix/sysv/linux/sh/le/libc.abilist
index 7d01add713..f876e152b7 100644
--- a/sysdeps/unix/sysv/linux/sh/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sh/le/libc.abilist
@@ -2391,6 +2391,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
index b5ef3247d7..a6fa1a1b29 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
@@ -2534,6 +2534,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
index 14ae7c8417..4f6166a8f1 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
@@ -2369,6 +2369,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/syscalls.list b/sysdeps/unix/sysv/linux/syscalls.list
index 62329abb49..29899eb264 100644
--- a/sysdeps/unix/sysv/linux/syscalls.list
+++ b/sysdeps/unix/sysv/linux/syscalls.list
@@ -99,3 +99,4 @@  pkey_alloc	EXTRA	pkey_alloc	i:ii	pkey_alloc
 pkey_free	EXTRA	pkey_free	i:i	pkey_free
 gettid          EXTRA   gettid          Ei:     __gettid	gettid
 tgkill          EXTRA   tgkill          i:iii   __tgkill	tgkill
+close_range     EXTRA   close_range     i:iii   __close_range   close_range
diff --git a/sysdeps/unix/sysv/linux/tst-close_range.c b/sysdeps/unix/sysv/linux/tst-close_range.c
new file mode 100644
index 0000000000..dccb6189c5
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/tst-close_range.c
@@ -0,0 +1,303 @@ 
+/* Test for the close_range system call.
+   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
+   <https://www.gnu.org/licenses/>.  */
+
+#include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <getopt.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <stdint.h>
+
+#include <array_length.h>
+#include <support/capture_subprocess.h>
+#include <support/check.h>
+#include <support/descriptors.h>
+#include <support/support.h>
+#include <support/xsched.h>
+#include <support/xunistd.h>
+
+#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;
+}
+
+static void
+close_range_test_max_upper_limit (void)
+{
+  struct support_descriptors *descrs = support_descriptors_list ();
+
+  int lowfd = open_multiple_temp_files ();
+
+  {
+    int r = close_range (lowfd, ~0U, 0);
+    if (r == -1 && errno == ENOSYS)
+      FAIL_UNSUPPORTED ("close_range not supported");
+    TEST_COMPARE (r, 0);
+  }
+
+  support_descriptors_check (descrs);
+  support_descriptors_free (descrs);
+}
+
+static void
+close_range_test_common (int lowfd, unsigned int flags)
+{
+  const int maximum_fd = lowfd + NFDS;
+  const int half_fd = lowfd + NFDS / 2;
+  const int gap_1 = maximum_fd - 8;
+
+  /* Close half of the descriptors and check result.  */
+  TEST_COMPARE (close_range (lowfd, half_fd, flags), 0);
+  for (int i = lowfd; i <= half_fd; i++)
+    {
+      TEST_COMPARE (fcntl (i, F_GETFL), -1);
+      TEST_COMPARE (errno, EBADF);
+    }
+  for (int i = half_fd + 1; i < maximum_fd; i++)
+    TEST_VERIFY (fcntl (i, F_GETFL) > -1);
+
+  /* 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);
+
+  TEST_COMPARE (close_range (half_fd + 1, gap_1, flags), 0);
+  for (int i = half_fd + 1; i < gap_1; i++)
+    {
+      TEST_COMPARE (fcntl (i, F_GETFL), -1);
+      TEST_COMPARE (errno, EBADF);
+    }
+  for (int i = gap_1 + 1; i < maximum_fd; i++)
+    TEST_VERIFY (fcntl (i, F_GETFL) > -1);
+
+  /* Close the remaining but the last one.  */
+  TEST_COMPARE (close_range (gap_1 + 1, maximum_fd - 1, flags), 0);
+  for (int i = gap_1 + 1; i < maximum_fd - 1; i++)
+    {
+      TEST_COMPARE (fcntl (i, F_GETFL), -1);
+      TEST_COMPARE (errno, EBADF);
+    }
+  TEST_VERIFY (fcntl (maximum_fd, F_GETFL) > -1);
+
+  /* Close the last one.  */
+  TEST_COMPARE (close_range (maximum_fd, maximum_fd, flags), 0);
+  TEST_COMPARE (fcntl (maximum_fd, F_GETFL), -1);
+  TEST_COMPARE (errno, EBADF);
+}
+
+/* Basic tests: check if the syscall close ranges with and without gaps.  */
+static void
+close_range_test (void)
+{
+  struct support_descriptors *descrs = support_descriptors_list ();
+
+  /* Check if the temporary file descriptor has no no gaps.  */
+  int lowfd = open_multiple_temp_files ();
+
+  close_range_test_common (lowfd, 0);
+
+  /* Double check by check the /proc.  */
+  support_descriptors_check (descrs);
+  support_descriptors_free (descrs);
+}
+
+_Noreturn static int
+close_range_test_fn (void *arg)
+{
+  int lowfd = (int) ((uintptr_t) arg);
+  close_range_test_common (lowfd, 0);
+  exit (EXIT_SUCCESS);
+}
+
+/* Check if a clone_range on a subprocess created with CLONE_FILES close
+   the shared file descriptor table entries in the parent.  */
+static void
+close_range_test_subprocess (void)
+{
+  struct support_descriptors *descrs = support_descriptors_list ();
+
+  /* Check if the temporary file descriptor has no no gaps.  */
+  int lowfd = open_multiple_temp_files ();
+
+  struct support_stack stack = support_stack_alloc (4096);
+
+  pid_t pid = xclone (close_range_test_fn, (void*) (uintptr_t) lowfd,
+		      stack.stack, stack.size, CLONE_FILES | SIGCHLD);
+  TEST_VERIFY_EXIT (pid > 0);
+  int status;
+  xwaitpid (pid, &status, 0);
+  TEST_VERIFY (WIFEXITED (status));
+  TEST_COMPARE (WEXITSTATUS (status), 0);
+
+  support_stack_free (&stack);
+
+  for (int i = lowfd; i < NFDS; i++)
+    TEST_VERIFY (fcntl (i, F_GETFL) < 0);
+
+  support_descriptors_check (descrs);
+  support_descriptors_free (descrs);
+}
+
+
+_Noreturn static int
+close_range_unshare_test_fn (void *arg)
+{
+  int lowfd = (int) ((uintptr_t) arg);
+  close_range_test_common (lowfd, CLOSE_RANGE_UNSHARE);
+  exit (EXIT_SUCCESS);
+}
+
+/* Check if a close_range with CLOSE_RANGE_UNSHARE issued from a subprocess
+   created with CLONE_FILES does not close the parent file descriptor list.  */
+static void
+close_range_unshare_test (void)
+{
+  struct support_descriptors *descrs1 = support_descriptors_list ();
+
+  /* Check if the temporary file descriptor has no no gaps.  */
+  int lowfd = open_multiple_temp_files ();
+
+  struct support_descriptors *descrs2 = support_descriptors_list ();
+
+  struct support_stack stack = support_stack_alloc (4096);
+
+  pid_t pid = xclone (close_range_unshare_test_fn, (void*) (uintptr_t) lowfd,
+		      stack.stack, stack.size, CLONE_FILES | SIGCHLD);
+  TEST_VERIFY_EXIT (pid > 0);
+  int status;
+  xwaitpid (pid, &status, 0);
+  TEST_VERIFY (WIFEXITED (status));
+  TEST_COMPARE (WEXITSTATUS (status), 0);
+
+  support_stack_free (&stack);
+
+  for (int i = 0; i < NFDS; i++)
+    TEST_VERIFY (fcntl (i, F_GETFL) > -1);
+
+  support_descriptors_check (descrs2);
+  support_descriptors_free (descrs2);
+
+  TEST_COMPARE (close_range (lowfd, lowfd + NFDS, 0), 0);
+
+  support_descriptors_check (descrs1);
+  support_descriptors_free (descrs1);
+}
+
+static bool
+is_in_array (int *arr, size_t len, int fd)
+{
+  bool r = false;
+  for (int i = 0; i < len; i++)
+    if (arr[i] == fd)
+      return true;
+  return r;
+}
+
+static void
+close_range_cloexec_test (void)
+{
+  /* Check if the temporary file descriptor has no no gaps.  */
+  const int lowfd = open_multiple_temp_files ();
+
+  const int maximum_fd = lowfd + NFDS;
+  const int half_fd = lowfd + NFDS / 2;
+  const int gap_1 = maximum_fd - 8;
+
+  /* Close half of the descriptors and check result.  */
+  int r = close_range (lowfd, half_fd, CLOSE_RANGE_CLOEXEC);
+  if (r == -1 && errno == EINVAL)
+    {
+      printf ("%s: CLOSE_RANGE_CLOEXEC not supported\n", __func__);
+      return;
+    }
+  for (int i = lowfd; i <= half_fd; i++)
+    {
+      int flags = fcntl (i, F_GETFD);
+      TEST_VERIFY (flags > -1);
+      TEST_COMPARE (flags & FD_CLOEXEC, FD_CLOEXEC);
+    }
+  for (int i = half_fd + 1; i < maximum_fd; i++)
+    TEST_VERIFY (fcntl (i, F_GETFL) > -1);
+
+  /* Create some gaps, close up to a threshold, and check result.  */
+  static int gap_close[] = { 57, 78, 81, 82, 84, 90 };
+  for (int i = 0; i < array_length (gap_close); i++)
+    xclose (gap_close[i]);
+
+  TEST_COMPARE (close_range (half_fd + 1, gap_1, CLOSE_RANGE_CLOEXEC), 0);
+  for (int i = half_fd + 1; i < gap_1; i++)
+    {
+      int flags = fcntl (i, F_GETFD);
+      if (is_in_array (gap_close, array_length (gap_close), i))
+        TEST_COMPARE (flags, -1);
+      else
+        {
+          TEST_VERIFY (flags > -1);
+          TEST_COMPARE (flags & FD_CLOEXEC, FD_CLOEXEC);
+        }
+    }
+  for (int i = gap_1 + 1; i < maximum_fd; i++)
+    TEST_VERIFY (fcntl (i, F_GETFL) > -1);
+
+  /* Close the remaining but the last one.  */
+  TEST_COMPARE (close_range (gap_1 + 1, maximum_fd - 1, CLOSE_RANGE_CLOEXEC),
+                0);
+  for (int i = gap_1 + 1; i < maximum_fd - 1; i++)
+    {
+      int flags = fcntl (i, F_GETFD);
+      TEST_VERIFY (flags > -1);
+      TEST_COMPARE (flags & FD_CLOEXEC, FD_CLOEXEC);
+    }
+  TEST_VERIFY (fcntl (maximum_fd, F_GETFL) > -1);
+
+  /* Close the last one.  */
+  TEST_COMPARE (close_range (maximum_fd, maximum_fd, CLOSE_RANGE_CLOEXEC), 0);
+  {
+    int flags = fcntl (maximum_fd, F_GETFD);
+    TEST_VERIFY (flags > -1);
+    TEST_COMPARE (flags & FD_CLOEXEC, FD_CLOEXEC);
+  }
+}
+
+static int
+do_test (void)
+{
+  close_range_test_max_upper_limit ();
+  close_range_test ();
+  close_range_test_subprocess ();
+  close_range_unshare_test ();
+  close_range_cloexec_test ();
+
+  return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
index 57c4f28d17..e12670c1a4 100644
--- a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
@@ -2325,6 +2325,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
index 47211abe4e..9b524d7b72 100644
--- a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
@@ -2424,6 +2424,7 @@  GLIBC_2.34 aio_suspend64 F
 GLIBC_2.34 aio_write F
 GLIBC_2.34 aio_write64 F
 GLIBC_2.34 call_once F
+GLIBC_2.34 close_range F
 GLIBC_2.34 cnd_broadcast F
 GLIBC_2.34 cnd_destroy F
 GLIBC_2.34 cnd_init F