From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
To: libc-alpha@sourceware.org
Subject: [PATCH v6 4/5] io: Add closefrom [BZ #10353]
Date: Wed, 23 Jun 2021 15:51:14 -0300 [thread overview]
Message-ID: <20210623185115.395812-5-adhemerval.zanella@linaro.org> (raw)
In-Reply-To: <20210623185115.395812-1-adhemerval.zanella@linaro.org>
The function closes all open file descriptors greater than or equal to
input argument. Negative values are clamped to 0, i.e, it will close
all file descriptors.
As indicated by the bug report, this is a common symbol provided by
different systems (Solaris, OpenBSD, NetBSD, FreeBSD) and, although
its has inherent issues with not taking in consideration internal libc
file descriptors (such as syslog), this is also a common feature used
in multiple projects [1][2][3][4][5].
The Linux fallback implementation iterates over /proc and close all
file descriptors sequentially. Although it was raised the questioning
whether getdents on /proc/self/fd might return disjointed entries
when file descriptor are closed; it does not seems the case on my
testing on multiple kernel (v4.18, v5.4, v5.9) and the same strategy
is used on different projects [1][2][3][5].
Also, the interface is set a fail-safe meaning that a failure in the
fallback results in a process abort.
Checked on x86_64-linux-gnu on kernel v5.11 and v5.4.
[1] https://github.com/systemd/systemd/blob/5238e9575906297608ff802a27e2ff9effa3b338/src/basic/fd-util.c#L217
[2] https://github.com/lxc/lxc/blob/ddf4b77e11a4d08f09b7b9cd13e593f8c047edc5/src/lxc/start.c#L236
[3] https://github.com/python/cpython/blob/9e4f2f3a6b8ee995c365e86d976937c141d867f8/Modules/_posixsubprocess.c#L220
[4] https://github.com/rust-lang/rust/blob/5f47c0613ed4eb46fca3633c1297364c09e5e451/src/libstd/sys/unix/process2.rs#L303-L308
[5] https://github.com/openjdk/jdk/blob/master/src/java.base/unix/native/libjava/childproc.c#L82
---
NEWS | 4 +
include/unistd.h | 1 +
io/Makefile | 4 +-
io/Versions | 3 +
io/closefrom.c | 34 ++++
io/tst-closefrom.c | 152 ++++++++++++++++++
manual/llio.texi | 10 ++
posix/unistd.h | 6 +
sysdeps/mach/hurd/i386/libc.abilist | 1 +
sysdeps/unix/sysv/linux/Makefile | 3 +-
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 | 35 ++++
sysdeps/unix/sysv/linux/closefrom_fallback.c | 97 +++++++++++
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 +
.../unix/sysv/linux/x86_64/64/libc.abilist | 1 +
.../unix/sysv/linux/x86_64/x32/libc.abilist | 1 +
44 files changed, 380 insertions(+), 2 deletions(-)
create mode 100644 io/closefrom.c
create mode 100644 io/tst-closefrom.c
create mode 100644 sysdeps/unix/sysv/linux/closefrom.c
create mode 100644 sysdeps/unix/sysv/linux/closefrom_fallback.c
diff --git a/NEWS b/NEWS
index a654694e01..031898d425 100644
--- a/NEWS
+++ b/NEWS
@@ -50,6 +50,10 @@ Major new features:
* On Linux, the close_range function has been added. It allows efficiently
closing a range of file descriptors on recent kernels (version 5.9).
+* The function closefrom has been added. It closes all file descriptors
+ greater than given integer. This function is a GNU extension, although it
+ also present in other systems.
+
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 34872d8b41..12044a8531 100644
--- a/include/unistd.h
+++ b/include/unistd.h
@@ -156,6 +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 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/io/Makefile b/io/Makefile
index 1a16990205..ebb7d56d67 100644
--- a/io/Makefile
+++ b/io/Makefile
@@ -56,7 +56,8 @@ routines := \
sendfile sendfile64 copy_file_range \
utimensat futimens file_change_detection \
fts64-time64 \
- ftw64-time64
+ ftw64-time64 \
+ closefrom
others := pwd
test-srcs := ftwtest ftwtest-time64
@@ -77,6 +78,7 @@ tests := test-utime test-stat test-stat2 test-lfs tst-getcwd \
tst-lutimes \
tst-futimens \
tst-utimensat \
+ tst-closefrom \
tests-time64 := \
tst-futimens-time64 \
diff --git a/io/Versions b/io/Versions
index 88caf76bbc..4e19540885 100644
--- a/io/Versions
+++ b/io/Versions
@@ -137,6 +137,9 @@ libc {
stat; stat64; fstat; fstat64; lstat; lstat64; fstatat; fstatat64;
mknod; mknodat;
}
+ GLIBC_2.34 {
+ closefrom;
+ }
GLIBC_PRIVATE {
__libc_fcntl64;
__fcntl_nocancel;
diff --git a/io/closefrom.c b/io/closefrom.c
new file mode 100644
index 0000000000..01660a7531
--- /dev/null
+++ b/io/closefrom.c
@@ -0,0 +1,34 @@
+/* Close a range of file descriptors.
+ 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 <stdio.h>
+#include <unistd.h>
+#include <not-cancel.h>
+
+void
+__closefrom (int lowfd)
+{
+ int maxfd = __getdtablesize ();
+ if (maxfd == -1)
+ __fortify_fail ("closefrom failed to get the file descriptor table size");
+
+ for (int i = 0; i < maxfd; i++)
+ if (i >= lowfd)
+ __close_nocancel_nostatus (i);
+}
+weak_alias (__closefrom, closefrom)
diff --git a/io/tst-closefrom.c b/io/tst-closefrom.c
new file mode 100644
index 0000000000..d4c187073c
--- /dev/null
+++ b/io/tst-closefrom.c
@@ -0,0 +1,152 @@
+/* Smoke test for the closefrom.
+ 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 <errno.h>
+#include <fcntl.h>
+#include <sys/resource.h>
+#include <unistd.h>
+
+#include <support/check.h>
+#include <support/descriptors.h>
+#include <support/xunistd.h>
+
+#include <array_length.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 int
+closefrom_test (void)
+{
+ struct support_descriptors *descrs = support_descriptors_list ();
+
+ int lowfd = open_multiple_temp_files ();
+
+ const int maximum_fd = lowfd + NFDS;
+ const int half_fd = lowfd + NFDS / 2;
+ const int gap = maximum_fd / 4;
+
+ /* Close half of the descriptors and check result. */
+ closefrom (half_fd);
+
+ for (int i = half_fd; i <= maximum_fd; i++)
+ {
+ TEST_COMPARE (fcntl (i, F_GETFL), -1);
+ TEST_COMPARE (errno, EBADF);
+ }
+ for (int i = 0; i < half_fd; i++)
+ TEST_VERIFY (fcntl (i, F_GETFL) > -1);
+
+ /* Create some gaps, close up to a threshold, and check result. */
+ xclose (lowfd + 35);
+ xclose (lowfd + 38);
+ xclose (lowfd + 42);
+ xclose (lowfd + 46);
+
+ /* Close half of the descriptors and check result. */
+ closefrom (gap);
+ for (int i = gap + 1; i < maximum_fd; i++)
+ {
+ TEST_COMPARE (fcntl (i, F_GETFL), -1);
+ TEST_COMPARE (errno, EBADF);
+ }
+ for (int i = 0; i < gap; i++)
+ TEST_VERIFY (fcntl (i, F_GETFL) > -1);
+
+ /* Close the remmaining but the last one. */
+ closefrom (lowfd + 1);
+ for (int i = lowfd + 1; i <= maximum_fd; i++)
+ {
+ TEST_COMPARE (fcntl (i, F_GETFL), -1);
+ TEST_COMPARE (errno, EBADF);
+ }
+ TEST_VERIFY (fcntl (lowfd, F_GETFL) > -1);
+
+ /* Close the last one. */
+ closefrom (lowfd);
+ TEST_COMPARE (fcntl (lowfd, F_GETFL), -1);
+ TEST_COMPARE (errno, EBADF);
+
+ /* Double check by check the /proc. */
+ support_descriptors_check (descrs);
+ support_descriptors_free (descrs);
+
+ return 0;
+}
+
+/* Check if closefrom works even when no new file descriptors can be
+ created. */
+static int
+closefrom_test_file_desc_limit (void)
+{
+ int max_fd = NFDS;
+ {
+ struct rlimit rl;
+ if (getrlimit (RLIMIT_NOFILE, &rl) == -1)
+ FAIL_EXIT1 ("getrlimit (RLIMIT_NOFILE): %m");
+
+ max_fd = (rl.rlim_cur < max_fd ? rl.rlim_cur : max_fd);
+ rl.rlim_cur = max_fd;
+
+ if (setrlimit (RLIMIT_NOFILE, &rl) == 1)
+ FAIL_EXIT1 ("setrlimit (RLIMIT_NOFILE): %m");
+ }
+
+ /* Exhauste the file descriptor limit. */
+ int lowfd = xopen ("/dev/null", O_RDONLY, 0600);
+ for (;;)
+ {
+ int fd = open ("/dev/null", O_RDONLY, 0600);
+ if (fd == -1)
+ {
+ if (errno != EMFILE)
+ FAIL_EXIT1 ("open: %m");
+ break;
+ }
+ TEST_VERIFY_EXIT (fd < max_fd);
+ }
+
+ closefrom (lowfd);
+ for (int i = lowfd; i < NFDS; i++)
+ {
+ TEST_COMPARE (fcntl (i, F_GETFL), -1);
+ TEST_COMPARE (errno, EBADF);
+ }
+
+ return 0;
+}
+
+static int
+do_test (void)
+{
+ closefrom_test ();
+ closefrom_test_file_desc_limit ();
+
+ return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/manual/llio.texi b/manual/llio.texi
index 3613ead72c..553e455e67 100644
--- a/manual/llio.texi
+++ b/manual/llio.texi
@@ -328,6 +328,16 @@ The maximum number of file descriptors is controlled by the
@end table
@end deftypefun
+@deftypefun void closefrom (int @var{lowfd})
+@standards{GNU, unistd.h}
+@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{@acsfd{}}}
+
+The function @code{closefrom} closes all file descriptors larger than or equal
+to @var{lowfd} then @var{lowfd}. This function is similar to call
+@code{close} applied to the specified file descriptor range.
+
+Already closed file descriptors are ignored.
+@end deftypefun
@node I/O Primitives
@section Input and Output Primitives
diff --git a/posix/unistd.h b/posix/unistd.h
index d9d8929f71..f3f7cb99c4 100644
--- a/posix/unistd.h
+++ b/posix/unistd.h
@@ -357,6 +357,12 @@ extern __off64_t lseek64 (int __fd, __off64_t __offset, int __whence)
__THROW. */
extern int close (int __fd);
+#ifdef __USE_MISC
+/* Close all open file descriptors greater than or equal to LOWFD.
+ Negative LOWFD is clamped to 0. */
+extern void closefrom (int __lowfd) __THROW;
+#endif
+
/* Read NBYTES into BUF from FD. Return the
number read, -1 for errors or 0 for EOF.
diff --git a/sysdeps/mach/hurd/i386/libc.abilist b/sysdeps/mach/hurd/i386/libc.abilist
index c3232ba32e..76d9e150f2 100644
--- a/sysdeps/mach/hurd/i386/libc.abilist
+++ b/sysdeps/mach/hurd/i386/libc.abilist
@@ -2218,6 +2218,7 @@ GLIBC_2.33 stat64 F
GLIBC_2.34 __isnanf128 F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 _hurd_libc_proc_init F
+GLIBC_2.34 closefrom F
GLIBC_2.34 dladdr F
GLIBC_2.34 dladdr1 F
GLIBC_2.34 dlclose F
diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile
index 35a90fd082..2f83da187f 100644
--- a/sysdeps/unix/sysv/linux/Makefile
+++ b/sysdeps/unix/sysv/linux/Makefile
@@ -64,7 +64,8 @@ sysdep_routines += adjtimex clone umount umount2 readahead sysctl \
pselect32 \
xstat fxstat lxstat xstat64 fxstat64 lxstat64 \
fxstatat fxstatat64 \
- xmknod xmknodat convert_scm_timestamps
+ xmknod xmknodat convert_scm_timestamps \
+ closefrom_fallback
CFLAGS-gethostid.c = -fexceptions
CFLAGS-tee.c = -fexceptions -fasynchronous-unwind-tables
diff --git a/sysdeps/unix/sysv/linux/aarch64/libc.abilist b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
index b4fe47f106..e5ec01277d 100644
--- a/sysdeps/unix/sysv/linux/aarch64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
@@ -2350,6 +2350,7 @@ 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 closefrom 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 7f2efdb4b2..19f7a7fca4 100644
--- a/sysdeps/unix/sysv/linux/alpha/libc.abilist
+++ b/sysdeps/unix/sysv/linux/alpha/libc.abilist
@@ -2443,6 +2443,7 @@ 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 closefrom 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 1dc13bbc63..ce6c13989a 100644
--- a/sysdeps/unix/sysv/linux/arc/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arc/libc.abilist
@@ -2109,6 +2109,7 @@ 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 closefrom 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 7ed5f95b0a..57e8456a3c 100644
--- a/sysdeps/unix/sysv/linux/arm/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arm/be/libc.abilist
@@ -280,6 +280,7 @@ 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 closefrom 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 3b2e38f2d5..de42eccbba 100644
--- a/sysdeps/unix/sysv/linux/arm/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arm/le/libc.abilist
@@ -277,6 +277,7 @@ 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 closefrom 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/closefrom.c b/sysdeps/unix/sysv/linux/closefrom.c
new file mode 100644
index 0000000000..f5d7342c2c
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/closefrom.c
@@ -0,0 +1,35 @@
+/* Close a range of file descriptors. 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
+ <https://www.gnu.org/licenses/>. */
+
+#include <stdio.h>
+#include <sys/param.h>
+#include <unistd.h>
+
+void
+__closefrom (int lowfd)
+{
+ int l = MAX (0, lowfd);
+
+ int r = __close_range (l, ~0U, 0);
+ if (r == 0)
+ return;
+
+ if (!__closefrom_fallback (l))
+ __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
new file mode 100644
index 0000000000..61e71d388d
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/closefrom_fallback.c
@@ -0,0 +1,97 @@
+/* Close a range of file descriptors. 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
+ <https://www.gnu.org/licenses/>. */
+
+#include <arch-fd_to_filename.h>
+#include <dirent.h>
+#include <not-cancel.h>
+#include <stdbool.h>
+
+/* Fallback code: iterates over /proc/self/fd, closing each file descriptor
+ that fall on the criteria. */
+_Bool
+__closefrom_fallback (int from)
+{
+ bool ret = false;
+
+ int dirfd = __open_nocancel (FD_TO_FILENAME_PREFIX, O_RDONLY | O_DIRECTORY,
+ 0);
+ if (dirfd == -1)
+ {
+ /* The closefrom should work even when process can't open new files. */
+ if (errno == ENOENT)
+ goto err;
+
+ for (int i = from; i < INT_MAX; i++)
+ {
+ int r = __close_nocancel (i);
+ if (r == 0 || (r == -1 && errno != EBADF))
+ break;
+ }
+
+ dirfd = __open_nocancel (FD_TO_FILENAME_PREFIX, O_RDONLY | O_DIRECTORY,
+ 0);
+ if (dirfd == -1)
+ goto err;
+ }
+
+ char buffer[1024];
+ while (true)
+ {
+ ssize_t ret = __getdents64 (dirfd, buffer, sizeof (buffer));
+ if (ret == -1)
+ goto err;
+ else if (ret == 0)
+ break;
+
+ /* If any file descriptor is closed it resets the /proc/self position
+ read again from the start (to obtain any possible kernel update). */
+ bool closed = false;
+ char *begin = buffer, *end = buffer + ret;
+ while (begin != end)
+ {
+ unsigned short int d_reclen;
+ memcpy (&d_reclen, begin + offsetof (struct dirent64, d_reclen),
+ sizeof (d_reclen));
+ const char *dname = begin + offsetof (struct dirent64, d_name);
+ begin += d_reclen;
+
+ if (dname[0] == '.')
+ continue;
+
+ int fd = 0;
+ for (const char *s = dname; (unsigned int) (*s) - '0' < 10; s++)
+ fd = 10 * fd + (*s - '0');
+
+ if (fd == dirfd || fd < from)
+ continue;
+
+ /* We ignore close errors because EBADF, EINTR, and EIO means the
+ descriptor has been released. */
+ __close_nocancel (fd);
+ closed = true;
+ }
+
+ if (closed && __lseek (dirfd, 0, SEEK_SET) < 0)
+ goto err;
+ }
+
+ ret = true;
+err:
+ __close_nocancel (dirfd);
+ return ret;
+}
diff --git a/sysdeps/unix/sysv/linux/csky/libc.abilist b/sysdeps/unix/sysv/linux/csky/libc.abilist
index c67320e0a3..f95d5ebbeb 100644
--- a/sysdeps/unix/sysv/linux/csky/libc.abilist
+++ b/sysdeps/unix/sysv/linux/csky/libc.abilist
@@ -2369,6 +2369,7 @@ 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 closefrom 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 4d49b632b3..a9d7fb1a93 100644
--- a/sysdeps/unix/sysv/linux/hppa/libc.abilist
+++ b/sysdeps/unix/sysv/linux/hppa/libc.abilist
@@ -2323,6 +2323,7 @@ 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 closefrom 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 7fdd181a8d..1deab899b1 100644
--- a/sysdeps/unix/sysv/linux/i386/libc.abilist
+++ b/sysdeps/unix/sysv/linux/i386/libc.abilist
@@ -2507,6 +2507,7 @@ 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 closefrom 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 f719aa9ee4..13121df7e0 100644
--- a/sysdeps/unix/sysv/linux/ia64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/ia64/libc.abilist
@@ -2283,6 +2283,7 @@ 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 closefrom 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 3616c567e3..e4fb78bf8e 100644
--- a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
@@ -281,6 +281,7 @@ 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 closefrom 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 4180cdf07d..b21d6b04af 100644
--- a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
@@ -2450,6 +2450,7 @@ 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 closefrom 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 82f5959756..7386b5360c 100644
--- a/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
@@ -2420,6 +2420,7 @@ 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 closefrom 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 53fb9ffaf8..c4c3f18e4d 100644
--- a/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
@@ -2417,6 +2417,7 @@ 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 closefrom 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 76f8f675ea..b500aa4db3 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
@@ -2415,6 +2415,7 @@ 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 closefrom 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 9d294bfcf9..8260c3ba4f 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
@@ -2413,6 +2413,7 @@ 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 closefrom 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 44fb849bc9..b58b8eef2d 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
@@ -2421,6 +2421,7 @@ 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 closefrom 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 102ec2a2f9..3f19142fee 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
@@ -2339,6 +2339,7 @@ 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 closefrom 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 c5c6844a01..a1d7b0c25f 100644
--- a/sysdeps/unix/sysv/linux/nios2/libc.abilist
+++ b/sysdeps/unix/sysv/linux/nios2/libc.abilist
@@ -2459,6 +2459,7 @@ 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 closefrom 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 8111a6d886..1f81867311 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
@@ -2477,6 +2477,7 @@ 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 closefrom 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 f65efa3c54..9f74a84ead 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
@@ -2510,6 +2510,7 @@ 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 closefrom 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 7cce3dca8c..8add515ff4 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
@@ -2247,6 +2247,7 @@ 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 closefrom 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 65ccafb1d9..ab7489200b 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
@@ -2546,6 +2546,7 @@ 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 closefrom 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 a34c8c30fc..273c579b2d 100644
--- a/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
@@ -2111,6 +2111,7 @@ 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 closefrom 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 85a5815d7b..9ae1c2ea89 100644
--- a/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
@@ -2311,6 +2311,7 @@ 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 closefrom 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 b63b3a5f0e..622d19d754 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
@@ -2475,6 +2475,7 @@ 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 closefrom 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 b874e3d48f..464e4cefde 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
@@ -2284,6 +2284,7 @@ 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 closefrom 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 4eabae900d..d75a0ec228 100644
--- a/sysdeps/unix/sysv/linux/sh/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sh/be/libc.abilist
@@ -2330,6 +2330,7 @@ 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 closefrom 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 ad302d997f..0eaeffda80 100644
--- a/sysdeps/unix/sysv/linux/sh/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sh/le/libc.abilist
@@ -2327,6 +2327,7 @@ 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 closefrom 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 7c3f29d8b4..79e3d5a658 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
@@ -2468,6 +2468,7 @@ 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 closefrom 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 d1442eac11..727b767863 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
@@ -2304,6 +2304,7 @@ 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 closefrom 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_64/64/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
index 06274a69e8..fc84da9bae 100644
--- a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
@@ -2262,6 +2262,7 @@ 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 closefrom 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 98e05351a8..2c44f71119 100644
--- a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
@@ -2365,6 +2365,7 @@ 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 closefrom 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 ` [PATCH v6 3/5] linux: Add close_range Adhemerval Zanella
2021-06-27 17:23 ` Florian Weimer
2021-06-23 18:51 ` Adhemerval Zanella [this message]
2021-07-03 14:45 ` [PATCH v6 4/5] io: Add closefrom [BZ #10353] 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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