Re: [PATCH] reintroduce accept4

Michael Kerrisk
2008-11-14T15:24:22Z

Andrew,

> From: Ulrich Drepper <drepper@redhat.com>
>
> Introduce a new accept4() system call. The addition of this system call
> matches analogous changes in 2.6.27 (dup3(), evenfd2(), signalfd4(),
> inotify_init1(), epoll_create1(), pipe2()) which added new system calls
> that differed from analogous traditional system calls in adding a flags
> argument that can be used to access additional functionality.
>
> The accept4() system call is exactly the same as accept(), except that it
> adds a flags bit-mask argument. Two flags are initially implemented.
> (Most of the new system calls in 2.6.27 also had both of these flags.)

Add a para break here.

> SOCK_CLOEXEC causes the close-on-exec (FD_CLOEXEC) flag to be enabled for
> the new file descriptor returned by accept4(). This is a useful security
> feature to avoid leaking information in a multithreaded program where one
> thread is doing an accept() at the same time as another thread is doing a
> fork() plus exec().
>

This para break is in the wrong place.

> More details here: http://udrepper.livejournal.com/20407.html "Secure File
> Descriptor Handling", Ulrich Drepper) The other flag is SOCK_NONBLOCK,

The para break should actually be at the sentence break in the previous line.

Cheers,

Michael