2007-11-21 07:29:50

by Ulrich Drepper

[permalink] [raw]
Subject: [PATCHv5 3/5] Allow setting FD_CLOEXEC flag for new sockets

This is a first user of sys_indirect. Several of the socket-related system
calls which produce a file handle now can be passed an additional parameter
to set the FD_CLOEXEC flag.

include/asm-x86/ia32_unistd.h | 1 +
include/linux/indirect.h | 27 +++++++++++++++++++++++++++
net/socket.c | 21 +++++++++++++--------
3 files changed, 41 insertions(+), 8 deletions(-)


diff -u linux/include/linux/indirect.h linux/include/linux/indirect.h
--- linux/include/linux/indirect.h
+++ linux/include/linux/indirect.h
@@ -1,3 +1,4 @@
+#ifndef INDSYSCALL
#ifndef _LINUX_INDIRECT_H
#define _LINUX_INDIRECT_H

@@ -13,5 +14,31 @@
+ struct {
+ int flags;
+ } file_flags;
};

#define INDIRECT_PARAM(set, name) current->indirect_params.set.name

#endif
+#else
+
+/* Here comes the list of system calls which can be called through
+ sys_indirect. When the list if support system calls is needed the
+ file including this header is supposed to define a macro "INDSYSCALL"
+ which adds a prefix fitting to the use. If the resulting macro is
+ defined we generate a line
+ case MACRO:
+ */
+#if INDSYSCALL(accept)
+ case INDSYSCALL(accept):
+#endif
+#if INDSYSCALL(socket)
+ case INDSYSCALL(socket):
+#endif
+#if INDSYSCALL(socketcall)
+ case INDSYSCALL(socketcall):
+#endif
+#if INDSYSCALL(socketpair)
+ case INDSYSCALL(socketpair):
+#endif
+
+#endif
--- linux/include/asm-x86/ia32_unistd.h
+++ linux/include/asm-x86/ia32_unistd.h
@@ -12,6 +12,7 @@
#define __NR_ia32_exit 1
#define __NR_ia32_read 3
#define __NR_ia32_write 4
+#define __NR_ia32_socketcall 102
#define __NR_ia32_sigreturn 119
#define __NR_ia32_rt_sigreturn 173

diff -u linux/net/socket.c linux/net/socket.c
--- linux/net/socket.c
+++ linux/net/socket.c
@@ -344,11 +344,11 @@
* but we take care of internal coherence yet.
*/

-static int sock_alloc_fd(struct file **filep)
+static int sock_alloc_fd(struct file **filep, int flags)
{
int fd;

- fd = get_unused_fd();
+ fd = get_unused_fd_flags(flags);
if (likely(fd >= 0)) {
struct file *file = get_empty_filp();

@@ -391,10 +391,10 @@
return 0;
}

-int sock_map_fd(struct socket *sock)
+static int sock_map_fd_flags(struct socket *sock, int flags)
{
struct file *newfile;
- int fd = sock_alloc_fd(&newfile);
+ int fd = sock_alloc_fd(&newfile, flags);

if (likely(fd >= 0)) {
int err = sock_attach_fd(sock, newfile);
@@ -409,6 +409,11 @@
return fd;
}

+int sock_map_fd(struct socket *sock)
+{
+ return sock_map_fd_flags(sock, 0);
+}
+
static struct socket *sock_from_file(struct file *file, int *err)
{
if (file->f_op == &socket_file_ops)
@@ -1208,7 +1213,7 @@
if (retval < 0)
goto out;

- retval = sock_map_fd(sock);
+ retval = sock_map_fd_flags(sock, INDIRECT_PARAM(file_flags, flags));
if (retval < 0)
goto out_release;

@@ -1249,13 +1254,13 @@
if (err < 0)
goto out_release_both;

- fd1 = sock_alloc_fd(&newfile1);
+ fd1 = sock_alloc_fd(&newfile1, INDIRECT_PARAM(file_flags, flags));
if (unlikely(fd1 < 0)) {
err = fd1;
goto out_release_both;
}

- fd2 = sock_alloc_fd(&newfile2);
+ fd2 = sock_alloc_fd(&newfile2, INDIRECT_PARAM(file_flags, flags));
if (unlikely(fd2 < 0)) {
err = fd2;
put_filp(newfile1);
@@ -1411,7 +1416,7 @@
*/
__module_get(newsock->ops->owner);

- newfd = sock_alloc_fd(&newfile);
+ newfd = sock_alloc_fd(&newfile, INDIRECT_PARAM(file_flags, flags));
if (unlikely(newfd < 0)) {
err = newfd;
sock_release(newsock);