flag parameters: socket and socketpair
This patch adds support for flag values which are ORed to the type passwd
to socket and socketpair. The additional code is minimal. The flag
values in this implementation can and must match the O_* flags. This
avoids overhead in the conversion.
The internal functions sock_alloc_fd and sock_map_fd get a new parameters
and all callers are changed.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#include <netinet/in.h>
#include <sys/socket.h>
#define PORT 57392
/* For Linux these must be the same. */
#define SOCK_CLOEXEC O_CLOEXEC
int
main (void)
{
int fd;
fd = socket (PF_INET, SOCK_STREAM, 0);
if (fd == -1)
{
puts ("socket(0) failed");
return 1;
}
int coe = fcntl (fd, F_GETFD);
if (coe == -1)
{
puts ("fcntl failed");
return 1;
}
if (coe & FD_CLOEXEC)
{
puts ("socket(0) set close-on-exec flag");
return 1;
}
close (fd);
fd = socket (PF_INET, SOCK_STREAM|SOCK_CLOEXEC, 0);
if (fd == -1)
{
puts ("socket(SOCK_CLOEXEC) failed");
return 1;
}
coe = fcntl (fd, F_GETFD);
if (coe == -1)
{
puts ("fcntl failed");
return 1;
}
if ((coe & FD_CLOEXEC) == 0)
{
puts ("socket(SOCK_CLOEXEC) does not set close-on-exec flag");
return 1;
}
close (fd);
int fds[2];
if (socketpair (PF_UNIX, SOCK_STREAM, 0, fds) == -1)
{
puts ("socketpair(0) failed");
return 1;
}
for (int i = 0; i < 2; ++i)
{
coe = fcntl (fds[i], F_GETFD);
if (coe == -1)
{
puts ("fcntl failed");
return 1;
}
if (coe & FD_CLOEXEC)
{
printf ("socketpair(0) set close-on-exec flag for fds[%d]\n", i);
return 1;
}
close (fds[i]);
}
if (socketpair (PF_UNIX, SOCK_STREAM|SOCK_CLOEXEC, 0, fds) == -1)
{
puts ("socketpair(SOCK_CLOEXEC) failed");
return 1;
}
for (int i = 0; i < 2; ++i)
{
coe = fcntl (fds[i], F_GETFD);
if (coe == -1)
{
puts ("fcntl failed");
return 1;
}
if ((coe & FD_CLOEXEC) == 0)
{
printf ("socketpair(SOCK_CLOEXEC) does not set close-on-exec flag for fds[%d]\n", i);
return 1;
}
close (fds[i]);
}
puts ("OK");
return 0;
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Acked-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/net/socket.c b/net/socket.c
index 1ba57d8..64601f9 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -349,11 +349,11 @@
* 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();
@@ -396,10 +396,10 @@
return 0;
}
-int sock_map_fd(struct socket *sock)
+int sock_map_fd(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);
@@ -1218,12 +1218,18 @@
{
int retval;
struct socket *sock;
+ int flags;
+
+ flags = type & ~SOCK_TYPE_MASK;
+ if (flags & ~SOCK_CLOEXEC)
+ return -EINVAL;
+ type &= SOCK_TYPE_MASK;
retval = sock_create(family, type, protocol, &sock);
if (retval < 0)
goto out;
- retval = sock_map_fd(sock);
+ retval = sock_map_fd(sock, flags & O_CLOEXEC);
if (retval < 0)
goto out_release;
@@ -1246,6 +1252,12 @@
struct socket *sock1, *sock2;
int fd1, fd2, err;
struct file *newfile1, *newfile2;
+ int flags;
+
+ flags = type & ~SOCK_TYPE_MASK;
+ if (flags & ~SOCK_CLOEXEC)
+ return -EINVAL;
+ type &= SOCK_TYPE_MASK;
/*
* Obtain the first socket and check if the underlying protocol
@@ -1264,13 +1276,13 @@
if (err < 0)
goto out_release_both;
- fd1 = sock_alloc_fd(&newfile1);
+ fd1 = sock_alloc_fd(&newfile1, flags & O_CLOEXEC);
if (unlikely(fd1 < 0)) {
err = fd1;
goto out_release_both;
}
- fd2 = sock_alloc_fd(&newfile2);
+ fd2 = sock_alloc_fd(&newfile2, flags & O_CLOEXEC);
if (unlikely(fd2 < 0)) {
err = fd2;
put_filp(newfile1);
@@ -1426,7 +1438,7 @@
*/
__module_get(newsock->ops->owner);
- newfd = sock_alloc_fd(&newfile);
+ newfd = sock_alloc_fd(&newfile, 0);
if (unlikely(newfd < 0)) {
err = newfd;
sock_release(newsock);