flag parameters: paccept w/out set_restore_sigmask (c019bbc6) · Commits · 戴 / test

Some platforms do not have support to restore the signal mask in the return path from a syscall. For those platforms syscalls like pselect are not defined at all. This is, I think, not a good choice for paccept() since paccept() adds more value on top of accept() than just the signal mask handling. Therefore this patch defines a scaled down version of the sys_paccept function for those platforms. It returns -EINVAL in case the signal mask is non-NULL but behaves the same otherwise. Note that I explicitly included <linux/thread_info.h>. I saw that it is currently included but indirectly two levels down. There is too much risk in relying on this. The header might change and then suddenly the function definition would change without anyone immediately noticing. Signed-off-by:

Ulrich Drepper <drepper@redhat.com> Cc: Davide Libenzi <davidel@xmailserver.org> Cc: Michael Kerrisk <mtk.manpages@googlemail.com> Signed-off-by:

Andrew Morton <akpm@linux-foundation.org> Signed-off-by:

Linus Torvalds <torvalds@linux-foundation.org>

include/linux/net.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -102,6 +102,9 @@ enum sock_type {

		/* Flags for socket, socketpair, paccept */
		#define SOCK_CLOEXEC O_CLOEXEC
		#ifndef SOCK_NONBLOCK
		#define SOCK_NONBLOCK O_NONBLOCK
		#endif

		#endif /* ARCH_HAS_SOCKET_TYPES */

net/socket.c

+17 −0

Original line number	Diff line number	Diff line
		@@ -69,6 +69,7 @@
		#include <linux/proc_fs.h>
		#include <linux/seq_file.h>
		#include <linux/mutex.h>
		#include <linux/thread_info.h>
		#include <linux/wanrouter.h>
		#include <linux/if_bridge.h>
		#include <linux/if_frad.h>
		@@ -1504,6 +1505,7 @@ out_fd:
		goto out_put;
		}

		#ifdef HAVE_SET_RESTORE_SIGMASK
		asmlinkage long sys_paccept(int fd, struct sockaddr __user *upeer_sockaddr,
		int __user *upeer_addrlen,
		const sigset_t __user *sigmask,
		@@ -1541,6 +1543,21 @@ asmlinkage long sys_paccept(int fd, struct sockaddr __user *upeer_sockaddr,

		return ret;
		}
		#else
		asmlinkage long sys_paccept(int fd, struct sockaddr __user *upeer_sockaddr,
		int __user *upeer_addrlen,
		const sigset_t __user *sigmask,
		size_t sigsetsize, int flags)
		{
		/* The platform does not support restoring the signal mask in the
		* return path. So we do not allow using paccept() with a signal
		* mask. */
		if (sigmask)
		return -EINVAL;

		return do_accept(fd, upeer_sockaddr, upeer_addrlen, flags);
		}
		#endif

		asmlinkage long sys_accept(int fd, struct sockaddr __user *upeer_sockaddr,
		int __user *upeer_addrlen)

Admin message