From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
To: libc-alpha@sourceware.org
Subject: [PATCH v6 3/5] linux: Add close_range
Date: Wed, 23 Jun 2021 15:51:13 -0300 [thread overview]
Message-ID: <20210623185115.395812-4-adhemerval.zanella@linaro.org> (raw)
In-Reply-To: <20210623185115.395812-1-adhemerval.zanella@linaro.org>
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 | 45 +++
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, 415 insertions(+), 1 deletion(-)
create mode 100644 include/bits/unistd_ext.h
create mode 100644 sysdeps/unix/sysv/linux/tst-close_range.c
diff --git a/NEWS b/NEWS
index 48d77d706f..a654694e01 100644
--- a/NEWS
+++ b/NEWS
@@ -47,6 +47,9 @@ Major new features:
with names ending with .conf to logically classify the converter modules in
that directory.
+* 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 cbc4909fd5..3613ead72c 100644
--- a/manual/llio.texi
+++ b/manual/llio.texi
@@ -284,6 +284,51 @@ 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
+@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 88d7cd7c1b..35a90fd082 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 ea0b22d7af..c16c8f5acb 100644
--- a/sysdeps/unix/sysv/linux/Versions
+++ b/sysdeps/unix/sysv/linux/Versions
@@ -270,6 +270,7 @@ 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 42e240e284..b4fe47f106 100644
--- a/sysdeps/unix/sysv/linux/aarch64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
@@ -2349,6 +2349,7 @@ GLIBC_2.34 __pthread_unwind_next F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 fad54555dc..7f2efdb4b2 100644
--- a/sysdeps/unix/sysv/linux/alpha/libc.abilist
+++ b/sysdeps/unix/sysv/linux/alpha/libc.abilist
@@ -2442,6 +2442,7 @@ GLIBC_2.34 __pthread_unwind_next F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 907716ec39..1dc13bbc63 100644
--- a/sysdeps/unix/sysv/linux/arc/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arc/libc.abilist
@@ -2108,6 +2108,7 @@ GLIBC_2.34 __pthread_unwind_next F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 50f987a429..7ed5f95b0a 100644
--- a/sysdeps/unix/sysv/linux/arm/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arm/be/libc.abilist
@@ -279,6 +279,7 @@ GLIBC_2.34 __wait4_time64 F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 bf9038af84..3b2e38f2d5 100644
--- a/sysdeps/unix/sysv/linux/arm/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arm/le/libc.abilist
@@ -276,6 +276,7 @@ GLIBC_2.34 __wait4_time64 F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 afb91f6f43..c67320e0a3 100644
--- a/sysdeps/unix/sysv/linux/csky/libc.abilist
+++ b/sysdeps/unix/sysv/linux/csky/libc.abilist
@@ -2368,6 +2368,7 @@ GLIBC_2.34 __wait4_time64 F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 125f8a269a..4d49b632b3 100644
--- a/sysdeps/unix/sysv/linux/hppa/libc.abilist
+++ b/sysdeps/unix/sysv/linux/hppa/libc.abilist
@@ -2322,6 +2322,7 @@ GLIBC_2.34 __wait4_time64 F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 517753bdd1..7fdd181a8d 100644
--- a/sysdeps/unix/sysv/linux/i386/libc.abilist
+++ b/sysdeps/unix/sysv/linux/i386/libc.abilist
@@ -2506,6 +2506,7 @@ GLIBC_2.34 __wait4_time64 F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 23d0928360..f719aa9ee4 100644
--- a/sysdeps/unix/sysv/linux/ia64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/ia64/libc.abilist
@@ -2282,6 +2282,7 @@ GLIBC_2.34 __pthread_unwind_next F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 dd5fb50b18..3616c567e3 100644
--- a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
@@ -280,6 +280,7 @@ GLIBC_2.34 __wait4_time64 F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 cb1d553361..4180cdf07d 100644
--- a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
@@ -2449,6 +2449,7 @@ GLIBC_2.34 __wait4_time64 F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 6a20a6fdf2..82f5959756 100644
--- a/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
@@ -2419,6 +2419,7 @@ GLIBC_2.34 __wait4_time64 F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 4c21cbb64d..53fb9ffaf8 100644
--- a/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
@@ -2416,6 +2416,7 @@ GLIBC_2.34 __wait4_time64 F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 f83ba2f780..76f8f675ea 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
@@ -2414,6 +2414,7 @@ GLIBC_2.34 __wait4_time64 F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 347bbddb94..9d294bfcf9 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
@@ -2412,6 +2412,7 @@ GLIBC_2.34 __wait4_time64 F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 26b7ab529b..44fb849bc9 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
@@ -2420,6 +2420,7 @@ GLIBC_2.34 __wait4_time64 F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 e667b0e553..102ec2a2f9 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
@@ -2338,6 +2338,7 @@ GLIBC_2.34 __pthread_unwind_next F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 89a1cc7da6..c5c6844a01 100644
--- a/sysdeps/unix/sysv/linux/nios2/libc.abilist
+++ b/sysdeps/unix/sysv/linux/nios2/libc.abilist
@@ -2458,6 +2458,7 @@ GLIBC_2.34 __wait4_time64 F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 f364c5219e..8111a6d886 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
@@ -2476,6 +2476,7 @@ GLIBC_2.34 __wait4_time64 F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 f5bcc78afe..f65efa3c54 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
@@ -2509,6 +2509,7 @@ GLIBC_2.34 __wait4_time64 F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 6032716053..7cce3dca8c 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
@@ -2246,6 +2246,7 @@ GLIBC_2.34 __pthread_unwind_next F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 8c5494e1dc..65ccafb1d9 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
@@ -2545,6 +2545,7 @@ GLIBC_2.34 __pthread_unwind_next F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 d7db279c1e..a34c8c30fc 100644
--- a/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
@@ -2110,6 +2110,7 @@ GLIBC_2.34 __pthread_unwind_next F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 ef03dc0f9e..85a5815d7b 100644
--- a/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
@@ -2310,6 +2310,7 @@ GLIBC_2.34 __pthread_unwind_next F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 9118cb68ec..b63b3a5f0e 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
@@ -2474,6 +2474,7 @@ GLIBC_2.34 __wait4_time64 F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 66c01bd7e7..b874e3d48f 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
@@ -2283,6 +2283,7 @@ GLIBC_2.34 __pthread_unwind_next F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 c40eb412c2..4eabae900d 100644
--- a/sysdeps/unix/sysv/linux/sh/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sh/be/libc.abilist
@@ -2329,6 +2329,7 @@ GLIBC_2.34 __wait4_time64 F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 1412d33835..ad302d997f 100644
--- a/sysdeps/unix/sysv/linux/sh/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sh/le/libc.abilist
@@ -2326,6 +2326,7 @@ GLIBC_2.34 __wait4_time64 F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 7b55d34753..7c3f29d8b4 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
@@ -2467,6 +2467,7 @@ GLIBC_2.34 __wait4_time64 F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 cfd5f38864..d1442eac11 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
@@ -2303,6 +2303,7 @@ GLIBC_2.34 __pthread_unwind_next F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 01ec2bfa95..53575669c7 100644
--- a/sysdeps/unix/sysv/linux/syscalls.list
+++ b/sysdeps/unix/sysv/linux/syscalls.list
@@ -101,3 +101,4 @@ 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..86c9f08845
--- /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 17be05f14f..06274a69e8 100644
--- a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
@@ -2261,6 +2261,7 @@ GLIBC_2.34 __pthread_unwind_next F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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 a9db18906b..98e05351a8 100644
--- a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
@@ -2364,6 +2364,7 @@ GLIBC_2.34 __pthread_unwind_next F
GLIBC_2.34 _pthread_cleanup_pop F
GLIBC_2.34 _pthread_cleanup_push 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
--
2.30.2
next prev parent reply other threads:[~2021-06-23 18:51 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-23 18:51 [PATCH v6 0/5] Add close_range, closefrom, and posix_spawn_file_actions_closefrom_np Adhemerval Zanella
2021-06-23 18:51 ` [PATCH v6 1/5] support: Add support_stack_alloc Adhemerval Zanella
2021-06-24 9:15 ` Florian Weimer
2021-06-24 11:33 ` Adhemerval Zanella
2021-06-23 18:51 ` [PATCH v6 2/5] support: Add xclone Adhemerval Zanella
2021-06-24 9:15 ` Florian Weimer
2021-06-23 18:51 ` Adhemerval Zanella [this message]
2021-06-27 17:23 ` [PATCH v6 3/5] linux: Add close_range Florian Weimer
2021-06-23 18:51 ` [PATCH v6 4/5] io: Add closefrom [BZ #10353] Adhemerval Zanella
2021-07-03 14:45 ` Jonathon Anderson
2021-07-05 20:26 ` Adhemerval Zanella
2021-07-06 11:37 ` Florian Weimer
2021-06-23 18:51 ` [PATCH v6 5/5] posix: Add posix_spawn_file_actions_closefrom_np Adhemerval Zanella
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