Commit Graph

147 Commits

Author SHA1 Message Date
Jeff Roberson
374ae2a393 - Relax requirements for p_numthreads, p_threads, p_swtick, and p_nice from
requiring the per-process spinlock to only requiring the process lock.
 - Reflect these changes in the proc.h documentation and consumers throughout
   the kernel.  This is a substantial reduction in locking cost for these
   fields and was made possible by recent changes to threading support.
2008-03-19 06:19:01 +00:00
Jeff Roberson
6617724c5f Remove kernel support for M:N threading.
While the KSE project was quite successful in bringing threading to
FreeBSD, the M:N approach taken by the kse library was never developed
to its full potential.  Backwards compatibility will be provided via
libmap.conf for dynamically linked binaries and static binaries will
be broken.
2008-03-12 10:12:01 +00:00
Stephan Uphoff
dda7aec745 Use VM_FAULT_DIRTY to fault in pages for write access in
proc_rwmen.
Otherwise copy on write may create an anonymous page that is
not marked as dirty. Since  writing data to these pages
in this function also does not dirty these pages they may be
later discarded by the pagedaemon.
2007-11-08 19:35:36 +00:00
Jeff Roberson
8753688f03 - Fix from pr kern/115469; Don't redeliver a signal once it has been
handled by the target process.

Contributed by:	Tijl Coosemans <tijl@ulyssis.org>
Approved by:	re
2007-10-09 00:03:39 +00:00
Jeff Roberson
b61ce5b0e6 - Move all of the PS_ flags into either p_flag or td_flags.
- p_sflag was mostly protected by PROC_LOCK rather than the PROC_SLOCK or
   previously the sched_lock.  These bugs have existed for some time.
 - Allow swapout to try each thread in a process individually and then
   swapin the whole process if any of these fail.  This allows us to move
   most scheduler related swap flags into td_flags.
 - Keep ki_sflag for backwards compat but change all in source tools to
   use the new and more correct location of P_INMEM.

Reported by:	pho
Reviewed by:	attilio, kib
Approved by:	re (kensmith)
2007-09-17 05:31:39 +00:00
Jeff Roberson
982d11f836 Commit 14/14 of sched_lock decomposition.
- Use thread_lock() rather than sched_lock for per-thread scheduling
   sychronization.
 - Use the per-process spinlock rather than the sched_lock for per-process
   scheduling synchronization.

Tested by:      kris, current@
Tested on:      i386, amd64, ULE, 4BSD, libthr, libkse, PREEMPTION, etc.
Discussed with: kris, attilio, kmacy, jhb, julian, bde (small parts each)
2007-06-05 00:00:57 +00:00
Robert Watson
0c14ff0eb5 Remove 'MPSAFE' annotations from the comments above most system calls: all
system calls now enter without Giant held, and then in some cases, acquire
Giant explicitly.

Remove a number of other MPSAFE annotations in the credential code and
tweak one or two other adjacent comments.
2007-03-04 22:36:48 +00:00
John Birrell
8460a577a4 Make KSE a kernel option, turned on by default in all GENERIC
kernel configs except sun4v (which doesn't process signals properly
with KSE).

Reviewed by:	davidxu@
2006-10-26 21:42:22 +00:00
David Xu
ff7668079f Move sigqueue_take() call into proc_reparent(), this fixed bugs where
proc_reparent() is called but sigqueue_take() is forgotten.
2006-10-25 06:18:04 +00:00
Tom Rhodes
f51bf07af8 Close a race condition where num can be larger than tmp, giving the user
too large of a boundary.

Reported by:	Ilja Van Sprundel
2006-10-14 10:30:14 +00:00
Colin Percival
23a28f3a0d Fix a signedness bug.
MFC after:	3 days
Security:	Local DoS
2006-08-20 10:29:08 +00:00
John Baldwin
06ad42b2f7 Close some races between procfs/ptrace and exit(2):
- Reorder the events in exit(2) slightly so that we trigger the S_EXIT
  stop event earlier.  After we have signalled that, we set P_WEXIT and
  then wait for any processes with a hold on the vmspace via PHOLD to
  release it.  PHOLD now KASSERT()'s that P_WEXIT is clear when it is
  invoked, and PRELE now does a wakeup if P_WEXIT is set and p_lock drops
  to zero.
- Change proc_rwmem() to require that the processing read from has its
  vmspace held via PHOLD by the caller and get rid of all the junk to
  screw around with the vmspace reference count as we no longer need it.
- In ptrace() and pseudofs(), treat a process with P_WEXIT set as if it
  doesn't exist.
- Only do one PHOLD in kern_ptrace() now, and do it earlier so it covers
  FIX_SSTEP() (since on alpha at least this can end up calling proc_rwmem()
  to clear an earlier single-step simualted via a breakpoint).  We only
  do one to avoid races.  Also, by making the EINVAL error for unknown
  requests be part of the default: case in the switch, the various
  switch cases can now just break out to return which removes a _lot_ of
  duplicated PRELE and proc unlocks, etc.  Also, it fixes at least one bug
  where a LWP ptrace command could return EINVAL with the proc lock still
  held.
- Changed the locking for ptrace_single_step(), ptrace_set_pc(), and
  ptrace_clear_single_step() to always be called with the proc lock
  held (it was a mixed bag previously).  Alpha and arm have to drop
  the lock while the mess around with breakpoints, but other archs
  avoid extra lock release/acquires in ptrace().  I did have to fix a
  couple of other consumers in kern_kse and a few other places to
  hold the proc lock and PHOLD.

Tested by:	ps (1 mostly, but some bits of 2-4 as well)
MFC after:	1 week
2006-02-22 18:57:50 +00:00
Wayne Salamon
085a0d43ca Audit the arguments to the ptrace(2) system call.
Obtained from: TrustedBSD Project
Approved by: rwatson (mentor)
2006-02-14 01:18:31 +00:00
David Xu
ea8e65b0fa Add members pl_sigmask and pl_siglist into ptrace_lwpinfo to get lwp's
signal mask and pending signals.
2006-02-06 09:41:56 +00:00
David Xu
d7bc12b096 Avoid kernel panic when attaching a process which may not be stopped
by debugger, e.g process is dumping core. Only access p_xthread if
P_STOPPED_TRACE is set, this means thread is ready to exchange signal
with debugger, print a warning if P_STOPPED_TRACE is not set due to
some bugs in other code, if there is.

The patch has been tested by Anish Mistry mistry.7 at osu dot edu, and
is slightly adjusted.
2005-12-24 02:59:29 +00:00
David Xu
c20cedbfc9 Make sure pending SIGCHLD is removed from previous parent when process
is attached or detached.
2005-11-08 23:28:12 +00:00
David Xu
8c6d7a8db8 Fix a LOR between sched_lock and sleep queue lock. 2005-08-19 13:35:34 +00:00
Peter Wemm
62919d788b Jumbo-commit to enhance 32 bit application support on 64 bit kernels.
This is good enough to be able to run a RELENG_4 gdb binary against
a RELENG_4 application, along with various other tools (eg: 4.x gcore).
We use this at work.

ia32_reg.[ch]: handle the 32 bit register file format, used by ptrace,
	procfs and core dumps.
procfs_*regs.c: vary the format of proc/XXX/*regs depending on the client
	and target application.
procfs_map.c: Don't print a 64 bit value to 32 bit consumers, or their
	sscanf fails.  They expect an unsigned long.
imgact_elf.c: produce a valid 32 bit coredump for 32 bit apps.
sys_process.c: handle 32 bit consumers debugging 32 bit targets.  Note
	that 64 bit consumers can still debug 32 bit targets.

IA64 has got stubs for ia32_reg.c.

Known limitations: a 5.x/6.x gdb uses get/setcontext(), which isn't
implemented in the 32/64 wrapper yet.  We also make a tiny patch to
gdb pacify it over conflicting formats of ld-elf.so.1.

Approved by:	re
2005-06-30 07:49:22 +00:00
David Schultz
f7fdcd45f0 Add missing cases for PT_SYSCALL.
Found by:	Coverity Prevent analysis tool
2005-03-18 21:22:28 +00:00
Warner Losh
9454b2d864 /* -> /*- for copyright notices, minor format tweaks as necessary 2005-01-06 23:35:40 +00:00
David Schultz
6004362e66 Don't include sys/user.h merely for its side-effect of recursively
including other headers.
2004-11-27 06:51:39 +00:00
David Xu
1f2eac6cf3 Add pl_flags to ptrace_lwpinfo, two flags PL_FLAG_SA and PL_FLAG_BOUND
indicate that a thread is in UTS critical region.

Reviewed by: deischen
Approved by: marcel
2004-08-08 22:26:11 +00:00
Alan Cox
1a276a3f91 - Use atomic ops for updating the vmspace's refcnt and exitingcnt.
- Push down Giant into shmexit().  (Giant is acquired only if the vmspace
   contains shm segments.)
 - Eliminate the acquisition of Giant from proc_rwmem().
 - Reduce the scope of Giant in exit1(), uncovering the destruction of the
   address space.
2004-07-27 03:53:41 +00:00
David Xu
c3d88cbab8 Fix typo. 2004-07-17 23:15:41 +00:00
David Xu
ef9457becb Implement following commands: PT_CLEARSTEP, PT_SETSTEP, PT_SUSPEND
PT_RESUME, PT_GETNUMLWPS, PT_GETLWPLIST.
2004-07-13 07:25:24 +00:00
Marcel Moolenaar
fbc3247d81 Implement the PT_LWPINFO request. This request can be used by the
tracing process to obtain information about the LWP that caused the
traced process to stop. Debuggers can use this information to select
the thread currently running on the LWP as the current thread.

The request has been made compatible with NetBSD for as much as
possible. This implementation differs from NetBSD in the following
ways:
1.  The data argument is allowed to be smaller than the size of the
    ptrace_lwpinfo structure known to the kernel, but not 0. This
    is opposite to what NetBSD allows. The reason for this is that
    we can extend the structure without affecting older binaries.
2.  On NetBSD the tracing process is to set the pl_lwpid field to
    the Id of the LWP it wants information of. We don't do that.
    Our ptrace interface allows passing the LWP Id instead of the
    PID. The tracing process is to set the PID to the LWP Id it
    wants information of.
3.  When the PID is actually the PID of the tracing process, this
    request returns the information about the LWP that caused the
    process to stop. This was the whole purpose of the request in
    the first place.

When the traced process has exited, this request will return the
LWP Id 0, indicating that the process state is not the result of
an event specific to a LWP.
2004-07-12 05:07:50 +00:00
David Xu
f3b929bf42 Allow ptrace to deal with lwpid.
Reviewed by: marcel
2004-07-02 09:19:22 +00:00
John Baldwin
e43257aa7d Finish fixing up Alpha to work with an MP safe ptrace():
- ptrace_single_step() is no longer called with the proc lock held, so
  don't try to unlock it and then relock it.
- Push Giant down into proc_rwmem() instead of forcing all the consumers
  (including Alpha breakpoint support) to explicitly wrap calls to
  proc_rwmem() with Giant.

Tested by:	kensmith
2004-04-01 20:56:44 +00:00
Alan Cox
2b63e7f397 Use uiomove_fromphys() instead of pmap_qenter() and pmap_qremove() in
proc_rwmem().
2004-03-24 23:35:04 +00:00
John Baldwin
8ac61436e6 Drop the proc lock around calls to the MD functions ptrace_single_step(),
ptrace_set_pc(), and cpu_ptrace() so that those functions are free to
acquire Giant, sleep, etc.  We already do a PHOLD/PRELE around them so
that it is safe to sleep inside of these routines if necessary.  This
allows ptrace() to be marked MP safe again as it no longer triggers lock
order reversals on Alpha.

Tested by:	wilko
2004-03-15 18:48:28 +00:00
Don Lewis
cf93aa166c When reparenting a process in the PT_DETACH code, only set p_sigparent
to SIGCHLD if the new parent process is initproc.

MFC after:	2 weeks
2004-02-19 10:39:42 +00:00
Don Lewis
55b5f2a202 When reparenting a process to init, make sure that p_sigparent is
set to SIGCHLD.  This avoids the creation of orphaned Linux-threaded
zombies that init is unable to reap.  This can occur when the parent
process sets its SIGCHLD to SIG_IGN.  Fix a similar situation in the
PT_DETACH code.

Tested by:	"Steven Hartland" <killing AT multiplay.co.uk>
2004-02-11 22:06:02 +00:00
Robert Drehmel
ea924c4cd3 Implement preliminary support for the PT_SYSCALL command to ptrace(2). 2003-10-09 10:17:16 +00:00
Marcel Moolenaar
1c843354aa Add or finish support for machine dependent ptrace requests. When we
check for permissions, do it for all requests, not the known requests.
Later when we actually service the request we deal with the invalid
requests we previously caught earlier.

This commit changes the behaviour of the ptrace(2) interface for
boundary cases such as an unknown request without proper permissions.
Previously we would return EINVAL. Now we return EBUSY or EPERM.

Platforms need to define __HAVE_PTRACE_MACHDEP when they have MD
requests. This makes the prototype of cpu_ptrace() visible and
introduces a call to this function for all requests greater or
equal to PT_FIRSTMACH.

Silence on: audit
2003-08-15 05:25:06 +00:00
Jacques Vidrine
007e25d95a Add or correct range checking of signal numbers in system calls and
ioctls.

In the particular case of ptrace(), this commit more-or-less reverts
revision 1.53 of sys_process.c, which appears to have been erroneous.

Reviewed by:	iedowse, jhb
2003-08-10 23:04:55 +00:00
Alan Cox
c6eb850aac Background: When proc_rwmem() wired and mapped a page, it also added
a reference to the containing object.  The purpose of the reference
being to prevent the destruction of the object and an attempt to free
the wired page.  (Wired pages can't be freed.)  Unfortunately, this
approach does not work.  Some operations, like fork(2) that call
vm_object_split(), can move the wired page to a difference object,
thereby making the reference pointless and opening the possibility
of the wired page being freed.

A solution is to use vm_page_hold() in place of vm_page_wire().  Held
pages can be freed.  They are moved to a special hold queue until the
hold is released.

Submitted by:	tegge
2003-08-09 18:01:19 +00:00
Alan Cox
884962ae4e Use kmem_alloc_nofault() rather than kmem_alloc_pageable() in proc_rwmem().
See revision 1.140 of kern/sys_pipe.c for a detailed rationale.

Submitted by:	tegge
2003-08-02 17:08:21 +00:00
Alan Cox
c40f7377a4 Add vm object locking. 2003-06-11 06:43:48 +00:00
David E. O'Brien
677b542ea2 Use __FBSDID(). 2003-06-11 00:56:59 +00:00
John Baldwin
17b8a8a77a Push down Giant around calls to proc_rwmem() in kern_ptrace. kern_ptrace()
should now be MP safe.
2003-04-25 20:02:16 +00:00
John Baldwin
eeec6bab2e Prefer the proc lock to sched_lock when testing PS_INMEM now that it is
safe to do so.
2003-04-22 20:01:56 +00:00
John Baldwin
b68e08498f The sched_lock is not needed while clearing two of the P_STOPPED bits in
p_flag.  Also, the proc lock can't be recursed, so simplify an older proc
lock assertion.
2003-04-17 22:31:54 +00:00
Dag-Erling Smørgrav
4e8074eba2 Whitespace cleanup. 2003-03-19 00:33:38 +00:00
John Baldwin
5c0cc63c40 Add a missing PROC_UNLOCK in ptrace() for the PT_IO case.
PR:		kern/44065
Submitted by:	Mark Kettenis <kettenis@chello.nl>
2002-10-16 16:28:33 +00:00
Julian Elischer
71fad9fdee Completely redo thread states.
Reviewed by:	davidxu@freebsd.org
2002-09-11 08:13:56 +00:00
Peter Wemm
1ed8cb4870 Remove bogus fill_kinfo_proc() before ptrace_set_pc(). There was no need
for this.

Submitted by:	bde
2002-09-07 22:18:19 +00:00
David Xu
1279572a92 s/SGNL/SIG/
s/SNGL/SINGLE/
s/SNGLE/SINGLE/

Fix abbreviation for P_STOPPED_* etc flags, in original code they were
inconsistent and difficult to distinguish between them.

Approved by: julian (mentor)
2002-09-05 07:30:18 +00:00
Ian Dowse
012e544f12 Split up ptrace() into a wrapper that does the copying to and from
user space and a kern_ptrace() implementation. Use the kern_*()
version in the Linux emulation code to remove more stack gap uses.

Approved by:	des
2002-09-05 01:02:50 +00:00
Philippe Charnier
93b0017f88 Replace various spelling with FALLTHROUGH which is lint()able 2002-08-25 13:23:09 +00:00
Robert Watson
4f18efe220 Do preserve the error result from calling p_cansee() and use that when
failing because of the error.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, NAI Labs
2002-07-20 22:44:39 +00:00