diff options
| author | Ulrich Drepper <drepper@redhat.com> | 2007-08-11 02:56:12 +0000 |
|---|---|---|
| committer | Ulrich Drepper <drepper@redhat.com> | 2007-08-11 02:56:12 +0000 |
| commit | 7cf89e95994db2b6a96edac8688420a8415e45e8 (patch) | |
| tree | 39a96372cffe3f8739dbd42ff000301ab6f2fc44 /shadow/lckpwdf.c | |
| parent | d7e23b02a40384be1eaf00762ea36fd117c462cd (diff) | |
| download | glibc-7cf89e95994db2b6a96edac8688420a8415e45e8.tar.gz | |
* shadow/lckpwdf.c (__lckpwdf): Use O_CLOEXEC if possible.
Diffstat (limited to 'shadow/lckpwdf.c')
| -rw-r--r-- | shadow/lckpwdf.c | 42 |
1 files changed, 31 insertions, 11 deletions
diff --git a/shadow/lckpwdf.c b/shadow/lckpwdf.c index 67d9937ac2..2770fb5b33 100644 --- a/shadow/lckpwdf.c +++ b/shadow/lckpwdf.c @@ -1,5 +1,5 @@ /* Handle locking of password file. - Copyright (C) 1996,98,2000,02 Free Software Foundation, Inc. + Copyright (C) 1996, 1998, 2000, 2002, 2007 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996. @@ -26,6 +26,8 @@ #include <unistd.h> #include <sys/file.h> +#include <kernel-features.h> + /* Name of the lock file. */ #define PWD_LOCKFILE "/etc/.pwd.lock" @@ -96,20 +98,38 @@ __lckpwdf (void) /* Prevent problems caused by multiple threads. */ __libc_lock_lock (lock); - lock_fd = __open (PWD_LOCKFILE, O_WRONLY | O_CREAT, 0600); + int oflags = O_WRONLY | O_CREAT; +#ifdef O_CLOEXEC + oflags |= O_CLOEXEC; +#endif + lock_fd = __open (PWD_LOCKFILE, oflags, 0600); if (lock_fd == -1) /* Cannot create lock file. */ RETURN_CLOSE_FD (-1); - /* Make sure file gets correctly closed when process finished. */ - flags = __fcntl (lock_fd, F_GETFD, 0); - if (flags == -1) - /* Cannot get file flags. */ - RETURN_CLOSE_FD (-1); - flags |= FD_CLOEXEC; /* Close on exit. */ - if (__fcntl (lock_fd, F_SETFD, flags) < 0) - /* Cannot set new flags. */ - RETURN_CLOSE_FD (-1); +#ifndef __ASSUME_O_CLOEXEC +# ifdef O_CLOEXEC + if (__have_o_cloexec <= 0) +# endif + { + /* Make sure file gets correctly closed when process finished. */ + flags = __fcntl (lock_fd, F_GETFD, 0); + if (flags == -1) + /* Cannot get file flags. */ + RETURN_CLOSE_FD (-1); +# ifdef O_CLOEXEC + if (__have_o_cloexec == 0) + __have_o_cloexec = (flags & FD_CLOEXEC) == 0 ? -1 : 1; + if (__have_o_cloexec < 0) +# endif + { + flags |= FD_CLOEXEC; /* Close on exit. */ + if (__fcntl (lock_fd, F_SETFD, flags) < 0) + /* Cannot set new flags. */ + RETURN_CLOSE_FD (-1); + } + } +#endif /* Now we have to get exclusive write access. Since multiple process could try this we won't stop when it first fails. |