diff options
| -rw-r--r-- | ChangeLog | 10 | ||||
| -rw-r--r-- | include/unistd.h | 1 | ||||
| -rw-r--r-- | libio/iopopen.c | 80 | ||||
| -rw-r--r-- | posix/wordexp.c | 32 | ||||
| -rw-r--r-- | socket/have_sock_cloexec.c | 4 | ||||
| -rw-r--r-- | sysdeps/unix/sysv/linux/kernel-features.h | 1 |
6 files changed, 32 insertions, 96 deletions
@@ -1,5 +1,15 @@ 2017-04-18 Florian Weimer <fweimer@redhat.com> + * include/unistd.h (__have_pipe2): Remove declaration. + * socket/have_sock_cloexec.c (__have_pipe2): Remove definition. + * libio/iopopen.c (_IO_new_proc_open): Assume that pipe2 is + available. + * posix/wordexp.c (exec_comm_child, exec_comm): Likewise. + * sysdeps/unix/sysv/linux/kernel-features.h (__ASSUME_PIPE2): + Remove definition. + +2017-04-18 Florian Weimer <fweimer@redhat.com> + * malloc/malloc.c (cfree): Turn into compat symbol. (__cfree): Remove alias. * stdlib/stdlib.h (cfree): Remove declaration. diff --git a/include/unistd.h b/include/unistd.h index 16d68a1505..e15fa0e23d 100644 --- a/include/unistd.h +++ b/include/unistd.h @@ -171,7 +171,6 @@ extern int __libc_pause (void); /* Not cancelable variant. */ extern int __pause_nocancel (void) attribute_hidden; -extern int __have_pipe2 attribute_hidden; extern int __have_dup3 attribute_hidden; extern int __getlogin_r_loginuid (char *name, size_t namesize) diff --git a/libio/iopopen.c b/libio/iopopen.c index 08e29b44b0..95a12c90b5 100644 --- a/libio/iopopen.c +++ b/libio/iopopen.c @@ -140,29 +140,17 @@ _IO_new_proc_open (_IO_FILE *fp, const char *command, const char *mode) if (_IO_file_is_open (fp)) return NULL; -#ifdef O_CLOEXEC -# ifndef __ASSUME_PIPE2 - if (__have_pipe2 >= 0) -# endif - { - int r = __pipe2 (pipe_fds, O_CLOEXEC); -# ifndef __ASSUME_PIPE2 - if (__have_pipe2 == 0) - __have_pipe2 = r != -1 || errno != ENOSYS ? 1 : -1; - - if (__have_pipe2 > 0) -# endif - if (r < 0) - return NULL; - } -#endif -#ifndef __ASSUME_PIPE2 -# ifdef O_CLOEXEC - if (__have_pipe2 < 0) -# endif - if (__pipe (pipe_fds) < 0) - return NULL; -#endif + /* Atomically set the O_CLOEXEC flag for the pipe end used by the + child process (to avoid leaking the file descriptor in case of a + concurrent fork). This is later reverted in the child process. + When popen returns, the parent pipe end can be O_CLOEXEC or not, + depending on the 'e' open mode, but there is only one flag which + controls both descriptors. The parent end is adjusted below, + after creating the child process. (In the child process, the + parent end should be closed on execve, so O_CLOEXEC remains set + there.) */ + if (__pipe2 (pipe_fds, O_CLOEXEC) < 0) + return NULL; if (do_read) { @@ -183,27 +171,13 @@ _IO_new_proc_open (_IO_FILE *fp, const char *command, const char *mode) int child_std_end = do_read ? 1 : 0; struct _IO_proc_file *p; -#ifndef __ASSUME_PIPE2 - /* If we have pipe2 the descriptor is marked for close-on-exec. */ - _IO_close (parent_end); -#endif if (child_end != child_std_end) - { - _IO_dup2 (child_end, child_std_end); -#ifndef __ASSUME_PIPE2 - _IO_close (child_end); -#endif - } + _IO_dup2 (child_end, child_std_end); #ifdef O_CLOEXEC else - { - /* The descriptor is already the one we will use. But it must - not be marked close-on-exec. Undo the effects. */ -# ifndef __ASSUME_PIPE2 - if (__have_pipe2 > 0) -# endif - __fcntl (child_end, F_SETFD, 0); - } + /* The descriptor is already the one we will use. But it must + not be marked close-on-exec. Undo the effects. */ + __fcntl (child_end, F_SETFD, 0); #endif /* POSIX.2: "popen() shall ensure that any streams from previous popen() calls that remain open in the parent process are closed @@ -229,26 +203,10 @@ _IO_new_proc_open (_IO_FILE *fp, const char *command, const char *mode) return NULL; } - if (do_cloexec) - { -#ifndef __ASSUME_PIPE2 -# ifdef O_CLOEXEC - if (__have_pipe2 < 0) -# endif - __fcntl (parent_end, F_SETFD, FD_CLOEXEC); -#endif - } - else - { -#ifdef O_CLOEXEC - /* Undo the effects of the pipe2 call which set the - close-on-exec flag. */ -# ifndef __ASSUME_PIPE2 - if (__have_pipe2 > 0) -# endif - __fcntl (parent_end, F_SETFD, 0); -#endif - } + if (!do_cloexec) + /* Undo the effects of the pipe2 call which set the + close-on-exec flag. */ + __fcntl (parent_end, F_SETFD, 0); _IO_fileno (fp) = parent_end; diff --git a/posix/wordexp.c b/posix/wordexp.c index ba3f3ed4b6..8567c9fc50 100644 --- a/posix/wordexp.c +++ b/posix/wordexp.c @@ -836,10 +836,7 @@ exec_comm_child (char *comm, int *fildes, int showerr, int noexec) { #ifdef O_CLOEXEC /* Reset the close-on-exec flag (if necessary). */ -# ifndef __ASSUME_PIPE2 - if (__have_pipe2 > 0) -# endif - __fcntl (fildes[1], F_SETFD, 0); + __fcntl (fildes[1], F_SETFD, 0); #endif } @@ -905,31 +902,8 @@ exec_comm (char *comm, char **word, size_t *word_length, size_t *max_length, if (!comm || !*comm) return 0; -#ifdef O_CLOEXEC -# ifndef __ASSUME_PIPE2 - if (__have_pipe2 >= 0) -# endif - { - int r = __pipe2 (fildes, O_CLOEXEC); -# ifndef __ASSUME_PIPE2 - if (__have_pipe2 == 0) - __have_pipe2 = r != -1 || errno != ENOSYS ? 1 : -1; - - if (__have_pipe2 > 0) -# endif - if (r < 0) - /* Bad */ - return WRDE_NOSPACE; - } -#endif -#ifndef __ASSUME_PIPE2 -# ifdef O_CLOEXEC - if (__have_pipe2 < 0) -# endif - if (__pipe (fildes) < 0) - /* Bad */ - return WRDE_NOSPACE; -#endif + if (__pipe2 (fildes, O_CLOEXEC) < 0) + return WRDE_NOSPACE; again: if ((pid = __fork ()) < 0) diff --git a/socket/have_sock_cloexec.c b/socket/have_sock_cloexec.c index 70c730ed12..579577d895 100644 --- a/socket/have_sock_cloexec.c +++ b/socket/have_sock_cloexec.c @@ -19,10 +19,6 @@ #include <sys/socket.h> #include <kernel-features.h> -#if defined O_CLOEXEC && !defined __ASSUME_PIPE2 -int __have_pipe2; -#endif - #if defined O_CLOEXEC && !defined __ASSUME_DUP3 int __have_dup3; #endif diff --git a/sysdeps/unix/sysv/linux/kernel-features.h b/sysdeps/unix/sysv/linux/kernel-features.h index e6a2720e94..233e302c0d 100644 --- a/sysdeps/unix/sysv/linux/kernel-features.h +++ b/sysdeps/unix/sysv/linux/kernel-features.h @@ -74,7 +74,6 @@ /* Support for various CLOEXEC and NONBLOCK flags was added in 2.6.27. */ #define __ASSUME_IN_NONBLOCK 1 -#define __ASSUME_PIPE2 1 #define __ASSUME_DUP3 1 /* Support for accept4 functionality was added in 2.6.28, but for some |