A "process descriptor" file descriptor is used to manage processes
without using the PID namespace. This is required for Capsicum's
Capability Mode, where the PID namespace is unavailable.
New system calls pdfork(2) and pdkill(2) offer the functional equivalents
of fork(2) and kill(2). pdgetpid(2) allows querying the PID of the remote
process for debugging purposes. The currently-unimplemented pdwait(2) will,
in the future, allow querying rusage/exit status. In the interim, poll(2)
may be used to check (and wait for) process termination.
When a process is referenced by a process descriptor, it does not issue
SIGCHLD to the parent, making it suitable for use in libraries---a common
scenario when using library compartmentalisation from within large
applications (such as web browsers). Some observers may note a similarity
to Mach task ports; process descriptors provide a subset of this behaviour,
but in a UNIX style.
This feature is enabled by "options PROCDESC", but as with several other
Capsicum kernel features, is not enabled by default in GENERIC 9.0.
Reviewed by: jhb, kib
Approved by: re (kib), mentor (rwatson)
Sponsored by: Google Inc
These system calls have already been implemented in the kernel; now we
hook up libc symbols so userspace can drive them.
Approved by: re (kib), mentor (rwatson)
Sponsored by: Google Inc
- While here, remove a few C comments that don't seem to contribute
anything additional to the man page.
PR: 146047
Submitted by: arundel
MFC after: 3 days
vop_stdallocate() is filesystem agnostic and will run as slow as a
read/write loop in userspace; however, it serves to correctly
implement the functionality for filesystems that do not implement a
VOP_ALLOCATE.
Note that __FreeBSD_version was already bumped today to 900036 for any
ports which would like to use this function.
Also reserve space in the syscall table for posix_fadvise(2).
Reviewed by: -arch (previous version)
syscall assembly files. This results in conflicting dependencies and can
cause unexpected results for parallel builds. This is because the .c file
and the .S file both generate the same .o file.
Submitted by: Simon Gerraty <sjg@juniper.net>
Sponsored by: Juniper Networks
Calling rfork_thread(3) does not interoperate with pthreads and global state
is not properly protected.
Remove the BUGS section suggesting LinuxThreads entirely. With the current
pthread library libthr, all threads are kernel-level entities so there seems
little reason to use LinuxThreads.
it possible for the kernel to track login class the process is assigned to,
which is required for RCTL. This change also make setusercontext(3) call
setloginclass(2) and makes it possible to retrieve current login class using
id(1).
Reviewed by: kib (as part of a larger patch)
can link against them. Add man pages for the new system calls, with one
errant forward reference to changes not yet present in FreeBSD, but soon
will be.
Reviewed by: anderson
Obtained from: Capsicum Project
Sponsored by: Google, Inc.
Discussed with: benl, kris, pjd
MFC after: 3 months
As it was pointed out by Alan Cox, that no longer serves its purpose with
the modern UMA allocator compared to the old one used in 4.x days.
The removal of sysctl eliminates max_proc_mmap type overflow leading to
the broken mmap(2) seen with large amount of physical memory on arches
with factually unbound KVA space (such as amd64). It was found that
slightly less than 256GB of physmem was enough to trigger the overflow.
Reviewed by: alc, kib
Approved by: avg (mentor)
MFC after: 2 months
architectures that support this .note. In particular, do not unneccessary
emit the notes on ia64 and sparc64, which ABI require non-executable stacks.
Tested by: marcel
Because {NGROUPS_MAX} may become variable, its value should be obtained
using sysconf(3). If a #define is used anyway, it should be obtained by
including <limits.h> as that is in POSIX like getgroups(2) itself is.
<sys/param.h> is not in POSIX.
MFC after: 1 week
This is what SUSv4 requires, and also the only thing that works if strict
standards compliance is requested or mknodat() is needed.
PR: standards/123688
Submitted by: gcooper
MFC after: 1 week
you tag a socket with an uint32_t value. The cookie can then be
used by the kernel for various purposes, e.g. setting the skipto
rule or pipe number in ipfw (this is the reason SO_USER_COOKIE has
been implemented; however there is nothing ipfw-specific in its
implementation).
The ipfw-related code that uses the optopn will be committed separately.
This change adds a field to 'struct socket', but the struct is not
part of any driver or userland-visible ABI so the change should be
harmless.
See the discussion at
http://lists.freebsd.org/pipermail/freebsd-ipfw/2009-October/004001.html
Idea and code from Paul Joe, small modifications and manpage
changes by myself.
Submitted by: Paul Joe
MFC after: 1 week
flag. [1]
- Note that also fchflags(2) will return EPERM for attempts to set or
unset the SF_SNAPSHOT flag.
Submitted by: Garrett Cooper [1]
MFC after: 1 week
It's a bit more pedantic regarding .Bl list elements. This has an added
benefit of unbreaking the ipfw(8) manpage, where groff was silently
skipping one list element.
the first line of a script exceeded MAXSHELLCMDLEN characters, then
exec_imgact_shell() silently truncated the line and passed on the truncated
interpreter name or argument. Now, exec_imgact_shell() will fail and return
ENOEXEC, which is the commonly used errno among Unix variants for this type
of error. (2) Previously, exec_imgact_shell()'s check on the length of the
interpreter's name was ineffective. In other words, exec_imgact_shell()
could not possibly fail and return ENAMETOOLONG. The reason being that the
length of the interpreter name had to exceed MAXSHELLCMDLEN characters in
order that ENAMETOOLONG be returned. But, the search for the end of the
interpreter name stops after at most MAXSHELLCMDLEN - 2 characters are
scanned. (In the end, this particular error is eventually discovered
outside of exec_imgact_shell() and ENAMETOOLONG is returned. So, the real
effect of this second change is that the error is detected earlier, in
exec_imgact_shell().)
Update the definition of MAXINTERP to the actual limit on the size of
the interpreter name that has been in effect since r142453 (from
2005).
In collaboration with: kib
add a wrapper for it in libc and rework the code in libthr, the
system call still can return EINTR, we keep this feature.
Discussed on: thread
Reviewed by: jilles
their implementations aren't in the same files. Introduce LIBC_ARCH
and use that in preference to MACHINE_CPUARCH. Tested by amd64 and
powerpc64 builds (thanks nathanw@)
the separate .o for libc_pic.a. This prevents rtld from making the
symbol global.
Putting the stack_protector_compat.c into the public domain acknowledged
by kan.
Reviewed by: kan
MFC after: 2 weeks
number of host CPUs and osreldate.
This eliminates the last sysctl(2) calls from the dynamically linked image
startup.
No objections from: kan
Tested by: marius (sparc64)
MFC after: 1 month
