From abb3587fe939d469a44f2097bae361aabd269f3f Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Sat, 5 Sep 2009 22:04:36 +0200 Subject: CLOEXEC: use open(CLOEXEC) if exist; do not check fcntl(FD_CLOEXEC) failure text data bss dec hex filename - 370 0 0 370 172 libc/misc/dirent/opendir.o + 366 0 0 366 16e libc/misc/dirent/opendir.o - 375 4 0 379 17b libc/pwd_grp/lckpwdf.o + 356 4 0 360 168 libc/pwd_grp/lckpwdf.o - 248 0 0 248 f8 librt/shm.o + 209 0 0 209 d1 librt/shm.o Signed-off-by: Denys Vlasenko --- libc/misc/dirent/opendir.c | 21 +++++++------ libc/misc/utmp/utent.c | 31 +++++++++++--------- libc/pwd_grp/lckpwdf.c | 34 ++++++++-------------- .../sysdeps/unix/sysv/linux/mq_notify.c | 4 +-- librt/shm.c | 17 ++++++----- 5 files changed, 53 insertions(+), 54 deletions(-) diff --git a/libc/misc/dirent/opendir.c b/libc/misc/dirent/opendir.c index fa07d0052..70b30658e 100644 --- a/libc/misc/dirent/opendir.c +++ b/libc/misc/dirent/opendir.c @@ -81,28 +81,31 @@ DIR *opendir(const char *name) } # define O_DIRECTORY 0 #endif - if ((fd = open(name, O_RDONLY|O_NDELAY|O_DIRECTORY)) < 0) +#ifndef O_CLOEXEC +# define O_CLOEXEC 0 +#endif + fd = open(name, O_RDONLY|O_NDELAY|O_DIRECTORY|O_CLOEXEC); + if (fd < 0) return NULL; /* Note: we should check to make sure that between the stat() and open() * call, 'name' didnt change on us, but that's only if O_DIRECTORY isnt * defined and since Linux has supported it for like ever, i'm not going * to worry about it right now (if ever). */ - if (fstat(fd, &statbuf) < 0) - goto close_and_ret; - - /* According to POSIX, directory streams should be closed when - * exec. From "Anna Pluzhnikov" . - */ - if (fcntl(fd, F_SETFD, FD_CLOEXEC) < 0) { + if (fstat(fd, &statbuf) < 0) { int saved_errno; -close_and_ret: saved_errno = errno; close(fd); __set_errno(saved_errno); return NULL; } + /* According to POSIX, directory streams should be closed when + * exec. From "Anna Pluzhnikov" . + */ + if (O_CLOEXEC == 0) + fcntl(fd, F_SETFD, FD_CLOEXEC); + ptr = fd_to_DIR(fd, statbuf.st_blksize); if (!ptr) { close(fd); diff --git a/libc/misc/utmp/utent.c b/libc/misc/utmp/utent.c index f0700af21..7d8a2d3c1 100644 --- a/libc/misc/utmp/utent.c +++ b/libc/misc/utmp/utent.c @@ -34,24 +34,29 @@ static const char *static_ut_name = default_file_name; static void __setutent(void) { if (static_fd < 0) { - static_fd = open(static_ut_name, O_RDWR); +#ifndef O_CLOEXEC +# define O_CLOEXEC 0 +#endif + static_fd = open(static_ut_name, O_RDWR | O_CLOEXEC); if (static_fd < 0) { - static_fd = open(static_ut_name, O_RDONLY); + static_fd = open(static_ut_name, O_RDONLY | O_CLOEXEC); if (static_fd < 0) { return; /* static_fd remains < 0 */ } } - /* Make sure the file will be closed on exec() */ - fcntl(static_fd, F_SETFD, FD_CLOEXEC); - // thus far, {G,S}ETFD only has this single flag, - // and setting it never fails. - //int ret = fcntl(static_fd, F_GETFD, 0); - //if (ret >= 0) { - // ret = fcntl(static_fd, F_SETFD, ret | FD_CLOEXEC); - //} - //if (ret < 0) { - // static_fd = -1; - //} + if (O_CLOEXEC == 0) { + /* Make sure the file will be closed on exec() */ + fcntl(static_fd, F_SETFD, FD_CLOEXEC); + // thus far, {G,S}ETFD only has this single flag, + // and setting it never fails. + //int ret = fcntl(static_fd, F_GETFD, 0); + //if (ret >= 0) { + // ret = fcntl(static_fd, F_SETFD, ret | FD_CLOEXEC); + //} + //if (ret < 0) { + // static_fd = -1; + //} + } return; } lseek(static_fd, 0, SEEK_SET); diff --git a/libc/pwd_grp/lckpwdf.c b/libc/pwd_grp/lckpwdf.c index c0c8f0d90..68c46e02c 100644 --- a/libc/pwd_grp/lckpwdf.c +++ b/libc/pwd_grp/lckpwdf.c @@ -28,17 +28,6 @@ #include #include -/* Experimentally off - libc_hidden_proto(memset) */ -/* libc_hidden_proto(open) */ -/* libc_hidden_proto(fcntl) */ -/* libc_hidden_proto(close) */ -/* libc_hidden_proto(sigfillset) */ -/* libc_hidden_proto(sigaction) */ -/* libc_hidden_proto(sigprocmask) */ -/* libc_hidden_proto(sigaddset) */ -/* libc_hidden_proto(sigemptyset) */ -/* libc_hidden_proto(alarm) */ - /* How long to wait for getting the lock before returning with an error. */ #define TIMEOUT 15 /* sec */ @@ -56,7 +45,6 @@ static void noop_handler (int __sig); int lckpwdf (void) { - int flags; sigset_t saved_set; /* Saved set of caught signals. */ struct sigaction saved_act; /* Saved signal action. */ sigset_t new_set; /* New set of caught signals. */ @@ -72,16 +60,18 @@ lckpwdf (void) /* Prevent problems caused by multiple threads. */ __UCLIBC_MUTEX_LOCK(mylock); - lock_fd = open (_PATH_PASSWD, O_WRONLY); +#ifndef O_CLOEXEC +# define O_CLOEXEC 0 +#endif + lock_fd = open (_PATH_PASSWD, O_WRONLY | O_CLOEXEC); if (lock_fd == -1) { /* Cannot create lock file. */ - goto DONE; + goto DONE; } - /* Make sure file gets correctly closed when process finished. */ - flags = fcntl (lock_fd, F_GETFD); - flags |= FD_CLOEXEC; - fcntl (lock_fd, F_SETFD, flags); + if (O_CLOEXEC == 0) + fcntl (lock_fd, F_SETFD, FD_CLOEXEC); + /* Now we have to get exclusive write access. Since multiple process could try this we won't stop when it first fails. Instead we set a timeout for the system call. Once the timer @@ -91,7 +81,7 @@ lckpwdf (void) It is important that we don't change the signal state. We must restore the old signal behaviour. */ - memset (&new_act, '\0', sizeof (struct sigaction)); + memset (&new_act, '\0', sizeof (new_act)); new_act.sa_handler = noop_handler; __sigfillset (&new_act.sa_mask); @@ -125,7 +115,7 @@ lckpwdf (void) if (result < 0) { close(lock_fd); lock_fd = -1; - goto DONE; + goto DONE; } rv = 0; @@ -146,7 +136,7 @@ ulckpwdf (void) else { /* Prevent problems caused by multiple threads. */ - __UCLIBC_MUTEX_LOCK(mylock); + __UCLIBC_MUTEX_LOCK(mylock); result = close (lock_fd); @@ -154,7 +144,7 @@ ulckpwdf (void) lock_fd = -1; /* Clear mutex. */ - __UCLIBC_MUTEX_UNLOCK(mylock); + __UCLIBC_MUTEX_UNLOCK(mylock); } return result; diff --git a/libpthread/linuxthreads/sysdeps/unix/sysv/linux/mq_notify.c b/libpthread/linuxthreads/sysdeps/unix/sysv/linux/mq_notify.c index 31d614b40..a44d05135 100644 --- a/libpthread/linuxthreads/sysdeps/unix/sysv/linux/mq_notify.c +++ b/libpthread/linuxthreads/sysdeps/unix/sysv/linux/mq_notify.c @@ -163,8 +163,7 @@ init_mq_netlink (void) return; /* Make sure the descriptor is closed on exec. */ - if (fcntl (netlink_socket, F_SETFD, FD_CLOEXEC) != 0) - goto errout; + fcntl (netlink_socket, F_SETFD, FD_CLOEXEC); } int err = 1; @@ -213,7 +212,6 @@ init_mq_netlink (void) if (err != 0) { - errout: close_not_cancel_no_status (netlink_socket); netlink_socket = -1; } diff --git a/librt/shm.c b/librt/shm.c index f1ef0e708..f0a974059 100644 --- a/librt/shm.c +++ b/librt/shm.c @@ -71,13 +71,16 @@ int shm_open(const char *name, int oflag, mode_t mode) #else fd = open(shm_name, oflag, mode); if (fd >= 0) { - int fdflags = fcntl(fd, F_GETFD, 0); - if (fdflags >= 0) - fdflags = fcntl(fd, F_SETFD, fdflags | FD_CLOEXEC); - if (fdflags < 0) { - close(fd); - fd = -1; - } + fcntl(fd, F_SETFD, FD_CLOEXEC); + // thus far, {G,S}ETFD only has this single flag, + // and setting it never fails. + //int fdflags = fcntl(fd, F_GETFD); + //if (fdflags >= 0) + // fdflags = fcntl(fd, F_SETFD, fdflags | FD_CLOEXEC); + //if (fdflags < 0) { + // close(fd); + // fd = -1; + //} } #endif old_errno = errno; -- cgit v1.2.3