- Add Q3 report on atomic close-on-exec

Submitted by:	jilles
This commit is contained in:
Gabor Pali 2013-10-07 10:10:19 +00:00
parent e5bb48473e
commit 653214b679
Notes: svn2git 2020-12-08 03:00:23 +00:00
svn path=/head/; revision=42869

View file

@ -19,7 +19,7 @@
<!-- XXX: keep updating the number of entries -->
<p>Thanks to all the reporters for the excellent work! This report
contains 17 entries and we hope you enjoy reading it.</p>
contains 18 entries and we hope you enjoy reading it.</p>
<!-- XXX: set date for the next set of submissions -->
<p>The deadline for submissions covering between October and
@ -897,4 +897,45 @@
SDIO-capable slot.</task>
</help>
</project>
<project cat='kern'>
<title>Atomic "close-on-exec"</title>
<contact>
<person>
<name>
<given>Jilles</given>
<common>Tjoelker</common>
</name>
<email>jilles@FreeBSD.org</email>
</person>
</contact>
<links>
<url href="https://wiki.freebsd.org/AtomicCloseOnExec" />
</links>
<body>
<p>If threads or signal handlers call <tt>fork()</tt> and
<tt>exec()</tt>, file descriptors may be passed undesirably to
child processes, which may lead to hangs (if a pipe is not
closed), exceeding the file descriptor limit and security
problems (if the child process has lower privilege). One
solution is various new APIs that set the "close-on-exec" flag
atomically with allocating a file descriptor. Some existing
software will use the new features if present or will even
refuse to compile without them.</p>
<p>With <tt>mkostemp()</tt>, <tt>dup3()</tt>, and a change to
modes of <tt>fopen()</tt> and <tt>freopen()</tt>, everything
proposed in Austin Group issue #411 has now been implemented.
For all POSIX-specified functions that allocate file
descriptors, it is possible to request that the new descriptor
be set close-on-exec atomically.</p>
<p>Additionally, many file descriptors used internally by
<tt>libc</tt> and <tt>libutil</tt> now have the close-on-exec bit
set.</p>
</body>
</project>
</report>