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-rw-r--r--debian/patches/0001-procfs-fix-argument-parsing.patch36
-rw-r--r--debian/patches/0002-libports-use-protected-payloads-to-optimize-the-obje.patch689
-rw-r--r--debian/patches/series2
3 files changed, 727 insertions, 0 deletions
diff --git a/debian/patches/0001-procfs-fix-argument-parsing.patch b/debian/patches/0001-procfs-fix-argument-parsing.patch
new file mode 100644
index 00000000..668a852c
--- /dev/null
+++ b/debian/patches/0001-procfs-fix-argument-parsing.patch
@@ -0,0 +1,36 @@
+From 785f4aea18b5705e63609001d2aa12871a774804 Mon Sep 17 00:00:00 2001
+From: Justus Winter <4winter@informatik.uni-hamburg.de>
+Date: Tue, 7 Apr 2015 12:53:03 +0200
+Subject: [PATCH hurd 1/2] procfs: fix argument parsing
+
+* procfs/main.c (argp_parser): Fix argument parsing.
+---
+ procfs/main.c | 6 +++---
+ 1 file changed, 3 insertions(+), 3 deletions(-)
+
+diff --git a/procfs/main.c b/procfs/main.c
+index d07dea8..d775b32 100644
+--- a/procfs/main.c
++++ b/procfs/main.c
+@@ -120,15 +120,15 @@ argp_parser (int key, char *arg, struct argp_state *state)
+
+ case NODEV_KEY:
+ /* Ignored for compatibility with Linux' procfs. */
+- ;;
++ break;
+
+ case NOEXEC_KEY:
+ /* Ignored for compatibility with Linux' procfs. */
+- ;;
++ break;
+
+ case NOSUID_KEY:
+ /* Ignored for compatibility with Linux' procfs. */
+- ;;
++ break;
+
+ default:
+ return ARGP_ERR_UNKNOWN;
+--
+2.1.4
+
diff --git a/debian/patches/0002-libports-use-protected-payloads-to-optimize-the-obje.patch b/debian/patches/0002-libports-use-protected-payloads-to-optimize-the-obje.patch
new file mode 100644
index 00000000..25b7079c
--- /dev/null
+++ b/debian/patches/0002-libports-use-protected-payloads-to-optimize-the-obje.patch
@@ -0,0 +1,689 @@
+From e1e1748f92e4315c3b5864bce60ee60553c50aa5 Mon Sep 17 00:00:00 2001
+From: Justus Winter <4winter@informatik.uni-hamburg.de>
+Date: Sat, 23 Nov 2013 16:12:55 +0100
+Subject: [PATCH hurd 2/2] libports: use protected payloads to optimize the
+ object lookup
+
+* NEWS: Mention protected payloads.
+* libports/Makefile (SRCS): Add `port-deref-deferred.c'.
+* libports/create-internal.c (_ports_create_port_internal): Set the
+protected payload to the objects address.
+* libports/import-port.c (ports_import_port): Likewise.
+* libports/reallocate-from-external.c (ports_reallocate_from_external):
+Likewise.
+* libports/reallocate-port.c (ports_reallocate_port): Likewise.
+* libports/transfer-right.c (ports_transfer_right): Likewise.
+* libports/manage-multithread.c (ports_manage_port_operations_multithread):
+Use the protected payload for the object lookup if provided. Add
+thread pool management calls.
+* libports/manage-one-thread.c (ports_manage_port_operations_one_thread):
+Likewise.
+* libports/destroy-right.c (ports_destroy_right): Defer the
+dereferencing of outstanding send rights to avoid a port_info
+use-after-free.
+* libports/port-deref-deferred.c: New file.
+* libports/port-deref-deferred.h: Likewise.
+* libports/ports.h (struct port_bucket): New field `threadpool'.
+(ports_lookup_payload): Check `port_right'.
+---
+ NEWS | 2 +
+ libports/Makefile | 2 +-
+ libports/complete-deallocate.c | 5 +-
+ libports/create-bucket.c | 1 +
+ libports/create-internal.c | 6 +-
+ libports/destroy-right.c | 56 ++++++++++---
+ libports/import-port.c | 6 +-
+ libports/manage-multithread.c | 31 ++++++-
+ libports/manage-one-thread.c | 20 ++++-
+ libports/port-deref-deferred.c | 162 ++++++++++++++++++++++++++++++++++++
+ libports/port-deref-deferred.h | 87 +++++++++++++++++++
+ libports/ports.h | 6 ++
+ libports/reallocate-from-external.c | 4 +
+ libports/reallocate-port.c | 4 +
+ libports/transfer-right.c | 3 +
+ 15 files changed, 375 insertions(+), 20 deletions(-)
+ create mode 100644 libports/port-deref-deferred.c
+ create mode 100644 libports/port-deref-deferred.h
+
+diff --git a/NEWS b/NEWS
+index b047aed..18e1489 100644
+--- a/NEWS
++++ b/NEWS
+@@ -6,6 +6,8 @@ problems have been identified using static analysis and exercising
+ tools, and have subsequently been fixed.
+
+ The message dispatching code in the Hurd servers has been improved.
++Among other things, we now make use of the protected payloads
++introduced in GNU Mach 1.5.
+
+ The embedded gz and bz2 decompressor code has been removed, libz and
+ libbz2 is used instead.
+diff --git a/libports/Makefile b/libports/Makefile
+index f49cb9f..b8b82ee 100644
+--- a/libports/Makefile
++++ b/libports/Makefile
+@@ -36,7 +36,7 @@ SRCS = create-bucket.c create-class.c \
+ interrupt-operation.c interrupt-on-notify.c interrupt-notified-rpcs.c \
+ dead-name.c create-port.c import-port.c default-uninhibitable-rpcs.c \
+ claim-right.c transfer-right.c create-port-noinstall.c create-internal.c \
+- interrupted.c extern-inline.c
++ interrupted.c extern-inline.c port-deref-deferred.c
+
+ installhdrs = ports.h
+
+diff --git a/libports/complete-deallocate.c b/libports/complete-deallocate.c
+index 0d852f5..c81425e 100644
+--- a/libports/complete-deallocate.c
++++ b/libports/complete-deallocate.c
+@@ -27,7 +27,7 @@ _ports_complete_deallocate (struct port_info *pi)
+ {
+ assert ((pi->flags & PORT_HAS_SENDRIGHTS) == 0);
+
+- if (pi->port_right)
++ if (MACH_PORT_VALID (pi->port_right))
+ {
+ struct references result;
+
+@@ -37,7 +37,8 @@ _ports_complete_deallocate (struct port_info *pi)
+ {
+ /* A reference was reacquired through a hash table lookup.
+ It's fine, we didn't touch anything yet. */
+- pthread_mutex_unlock (&_ports_htable_lock);
++ assert (! "reacquired reference w/o send rights");
++ pthread_rwlock_unlock (&_ports_htable_lock);
+ return;
+ }
+
+diff --git a/libports/create-bucket.c b/libports/create-bucket.c
+index 2c5f1b6..82c00a4 100644
+--- a/libports/create-bucket.c
++++ b/libports/create-bucket.c
+@@ -48,5 +48,6 @@ ports_create_bucket ()
+
+ hurd_ihash_init (&ret->htable, offsetof (struct port_info, hentry));
+ ret->rpcs = ret->flags = ret->count = 0;
++ _ports_threadpool_init (&ret->threadpool);
+ return ret;
+ }
+diff --git a/libports/create-internal.c b/libports/create-internal.c
+index 2d85931..d79dc78 100644
+--- a/libports/create-internal.c
++++ b/libports/create-internal.c
+@@ -99,7 +99,11 @@ _ports_create_port_internal (struct port_class *class,
+ bucket->count++;
+ class->count++;
+ pthread_mutex_unlock (&_ports_lock);
+-
++
++ /* This is an optimization. It may fail. */
++ mach_port_set_protected_payload (mach_task_self (), port,
++ (unsigned long) pi);
++
+ if (install)
+ {
+ err = mach_port_move_member (mach_task_self (), pi->port_right,
+diff --git a/libports/destroy-right.c b/libports/destroy-right.c
+index 448b379..276255f 100644
+--- a/libports/destroy-right.c
++++ b/libports/destroy-right.c
+@@ -1,5 +1,5 @@
+ /*
+- Copyright (C) 1995, 1996, 1999 Free Software Foundation, Inc.
++ Copyright (C) 1995, 1996, 1999, 2014 Free Software Foundation, Inc.
+ Written by Michael I. Bushnell.
+
+ This file is part of the GNU Hurd.
+@@ -22,30 +22,62 @@
+ #include <hurd/ihash.h>
+ #include <assert.h>
+
++#include <pthread.h>
++#include <error.h>
++#include <time.h>
++#include <unistd.h>
++
+ error_t
+ ports_destroy_right (void *portstruct)
+ {
+ struct port_info *pi = portstruct;
++ mach_port_t port_right;
++ int defer = 0;
+ error_t err;
+
+- if (pi->port_right != MACH_PORT_NULL)
++ pthread_mutex_lock (&_ports_lock);
++ port_right = pi->port_right;
++ pi->port_right = MACH_PORT_DEAD;
++
++ if (pi->flags & PORT_HAS_SENDRIGHTS)
++ {
++ pi->flags &= ~PORT_HAS_SENDRIGHTS;
++
++ /* There are outstanding send rights, so we might get more
++ messages. Attached to the messages is a reference to the
++ port_info object. Of course we destroyed the receive right
++ these were send to above, but the message could already have
++ been dequeued to userspace.
++
++ Previously, those messages would have carried an stale name,
++ which would have caused a hash table lookup failure.
++ However, stale payloads results in port_info use-after-free.
++ Therefore, we cannot release the reference here, but defer
++ that instead until all currently running threads have gone
++ through a quiescent state. */
++ defer = 1;
++ }
++
++ if (MACH_PORT_VALID (port_right))
+ {
++ mach_port_clear_protected_payload (mach_task_self (), port_right);
++
+ pthread_rwlock_wrlock (&_ports_htable_lock);
+ hurd_ihash_locp_remove (&_ports_htable, pi->ports_htable_entry);
+ hurd_ihash_locp_remove (&pi->bucket->htable, pi->hentry);
+ pthread_rwlock_unlock (&_ports_htable_lock);
+- err = mach_port_mod_refs (mach_task_self (), pi->port_right,
+- MACH_PORT_RIGHT_RECEIVE, -1);
+- assert_perror (err);
+-
+- pi->port_right = MACH_PORT_NULL;
++ }
++ pthread_mutex_unlock (&_ports_lock);
+
+- if (pi->flags & PORT_HAS_SENDRIGHTS)
+- {
+- pi->flags &= ~PORT_HAS_SENDRIGHTS;
+- ports_port_deref (pi);
+- }
++ if (MACH_PORT_VALID (port_right))
++ {
++ err = mach_port_mod_refs (mach_task_self (), port_right,
++ MACH_PORT_RIGHT_RECEIVE, -1);
++ assert_perror (err);
+ }
+
++ if (defer)
++ _ports_port_deref_deferred (pi);
++
+ return 0;
+ }
+diff --git a/libports/import-port.c b/libports/import-port.c
+index c337c85..2c638e1 100644
+--- a/libports/import-port.c
++++ b/libports/import-port.c
+@@ -93,7 +93,11 @@ ports_import_port (struct port_class *class, struct port_bucket *bucket,
+ bucket->count++;
+ class->count++;
+ pthread_mutex_unlock (&_ports_lock);
+-
++
++ /* This is an optimization. It may fail. */
++ mach_port_set_protected_payload (mach_task_self (), port,
++ (unsigned long) pi);
++
+ mach_port_move_member (mach_task_self (), port, bucket->portset);
+
+ if (stat.mps_srights)
+diff --git a/libports/manage-multithread.c b/libports/manage-multithread.c
+index 58814d2..dcb6905 100644
+--- a/libports/manage-multithread.c
++++ b/libports/manage-multithread.c
+@@ -167,7 +167,21 @@ ports_manage_port_operations_multithread (struct port_bucket *bucket,
+ outp->RetCodeType = RetCodeType;
+ outp->RetCode = MIG_BAD_ID;
+
+- pi = ports_lookup_port (bucket, inp->msgh_local_port, 0);
++ if (MACH_MSGH_BITS_LOCAL (inp->msgh_bits) ==
++ MACH_MSG_TYPE_PROTECTED_PAYLOAD)
++ pi = ports_lookup_payload (bucket, inp->msgh_protected_payload, NULL);
++ else
++ {
++ pi = ports_lookup_port (bucket, inp->msgh_local_port, 0);
++ if (pi)
++ {
++ inp->msgh_bits = MACH_MSGH_BITS (
++ MACH_MSGH_BITS_REMOTE (inp->msgh_bits),
++ MACH_MSG_TYPE_PROTECTED_PAYLOAD);
++ inp->msgh_protected_payload = (unsigned long) pi;
++ }
++ }
++
+ if (pi)
+ {
+ error_t err = ports_begin_rpc (pi, inp->msgh_id, &link);
+@@ -203,10 +217,19 @@ ports_manage_port_operations_multithread (struct port_bucket *bucket,
+ void *
+ thread_function (void *arg)
+ {
++ struct ports_thread thread;
+ int master = (int) arg;
+ int timeout;
+ error_t err;
+
++ int synchronized_demuxer (mach_msg_header_t *inp,
++ mach_msg_header_t *outheadp)
++ {
++ int r = internal_demuxer (inp, outheadp);
++ _ports_thread_quiescent (&bucket->threadpool, &thread);
++ return r;
++ }
++
+ adjust_priority (__atomic_load_n (&totalthreads, __ATOMIC_RELAXED));
+
+ if (hook)
+@@ -217,10 +240,13 @@ ports_manage_port_operations_multithread (struct port_bucket *bucket,
+ else
+ timeout = thread_timeout;
+
++ _ports_thread_online (&bucket->threadpool, &thread);
++
+ startover:
+
+ do
+- err = mach_msg_server_timeout (internal_demuxer, 0, bucket->portset,
++ err = mach_msg_server_timeout (synchronized_demuxer,
++ 0, bucket->portset,
+ timeout ? MACH_RCV_TIMEOUT : 0,
+ timeout);
+ while (err != MACH_RCV_TIMED_OUT);
+@@ -240,6 +266,7 @@ ports_manage_port_operations_multithread (struct port_bucket *bucket,
+ }
+ __atomic_sub_fetch (&totalthreads, 1, __ATOMIC_RELAXED);
+ }
++ _ports_thread_offline (&bucket->threadpool, &thread);
+ return NULL;
+ }
+
+diff --git a/libports/manage-one-thread.c b/libports/manage-one-thread.c
+index cbd2df7..192907a 100644
+--- a/libports/manage-one-thread.c
++++ b/libports/manage-one-thread.c
+@@ -25,6 +25,7 @@ ports_manage_port_operations_one_thread (struct port_bucket *bucket,
+ ports_demuxer_type demuxer,
+ int timeout)
+ {
++ struct ports_thread thread;
+ error_t err;
+
+ int
+@@ -57,7 +58,21 @@ ports_manage_port_operations_one_thread (struct port_bucket *bucket,
+ outp->RetCodeType = RetCodeType;
+ outp->RetCode = MIG_BAD_ID;
+
+- pi = ports_lookup_port (bucket, inp->msgh_local_port, 0);
++ if (MACH_MSGH_BITS_LOCAL (inp->msgh_bits) ==
++ MACH_MSG_TYPE_PROTECTED_PAYLOAD)
++ pi = ports_lookup_payload (bucket, inp->msgh_protected_payload, NULL);
++ else
++ {
++ pi = ports_lookup_port (bucket, inp->msgh_local_port, 0);
++ if (pi)
++ {
++ inp->msgh_bits = MACH_MSGH_BITS (
++ MACH_MSGH_BITS_REMOTE (inp->msgh_bits),
++ MACH_MSG_TYPE_PROTECTED_PAYLOAD);
++ inp->msgh_protected_payload = (unsigned long) pi;
++ }
++ }
++
+ if (pi)
+ {
+ err = ports_begin_rpc (pi, inp->msgh_id, &link);
+@@ -83,6 +98,7 @@ ports_manage_port_operations_one_thread (struct port_bucket *bucket,
+ status = 1;
+ }
+
++ _ports_thread_quiescent (&bucket->threadpool, &thread);
+ return status;
+ }
+
+@@ -93,8 +109,10 @@ ports_manage_port_operations_one_thread (struct port_bucket *bucket,
+ zero. */
+ timeout = 0;
+
++ _ports_thread_online (&bucket->threadpool, &thread);
+ do
+ err = mach_msg_server_timeout (internal_demuxer, 0, bucket->portset,
+ timeout ? MACH_RCV_TIMEOUT : 0, timeout);
+ while (err != MACH_RCV_TIMED_OUT);
++ _ports_thread_offline (&bucket->threadpool, &thread);
+ }
+diff --git a/libports/port-deref-deferred.c b/libports/port-deref-deferred.c
+new file mode 100644
+index 0000000..f5b3fda
+--- /dev/null
++++ b/libports/port-deref-deferred.c
+@@ -0,0 +1,162 @@
++/* Delayed deallocation of port_info objects.
++
++ Copyright (C) 2015 Free Software Foundation, Inc.
++
++ Written by Justus Winter <4winter@informatik.uni-hamburg.de>
++
++ This file is part of the GNU Hurd.
++
++ The GNU Hurd is free software; you can redistribute it and/or
++ modify it under the terms of the GNU General Public License as
++ published by the Free Software Foundation; either version 2, or (at
++ your option) any later version.
++
++ The GNU Hurd is distributed in the hope that it will be useful, but
++ WITHOUT ANY WARRANTY; without even the implied warranty of
++ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
++ General Public License for more details.
++
++ You should have received a copy of the GNU General Public License
++ along with the GNU Hurd. If not, see <http://www.gnu.org/licenses/>. */
++
++#include "ports.h"
++#include <assert.h>
++
++#include <pthread.h>
++
++/*
++ * A threadpool has a color indicating which threads belong to the old
++ * generation.
++ */
++#define COLOR_BLACK 0
++#define COLOR_WHITE 1
++#define COLOR_INVALID ~0U
++
++static inline int
++valid_color (unsigned int c)
++{
++ return c == COLOR_BLACK || c == COLOR_WHITE;
++}
++
++static inline unsigned int
++flip_color (unsigned int c)
++{
++ assert (valid_color (c));
++ return ! c;
++}
++
++/* Initialize the thread pool. */
++void
++_ports_threadpool_init (struct ports_threadpool *pool)
++{
++ pthread_spin_init (&pool->lock, PTHREAD_PROCESS_PRIVATE);
++ pool->color = COLOR_BLACK;
++ pool->old_threads = 0;
++ pool->old_objects = NULL;
++ pool->young_threads = 0;
++ pool->young_objects = NULL;
++}
++
++/* Turn all young objects and threads into old ones. */
++static inline void
++flip_generations (struct ports_threadpool *pool)
++{
++ assert (pool->old_threads == 0);
++ pool->old_threads = pool->young_threads;
++ pool->old_objects = pool->young_objects;
++ pool->young_threads = 0;
++ pool->young_objects = NULL;
++ pool->color = flip_color (pool->color);
++}
++
++/* Called by a thread to join a thread pool. */
++void
++_ports_thread_online (struct ports_threadpool *pool,
++ struct ports_thread *thread)
++{
++ pthread_spin_lock (&pool->lock);
++ thread->color = flip_color (pool->color);
++ pool->young_threads += 1;
++ pthread_spin_unlock (&pool->lock);
++}
++
++struct pi_list
++{
++ struct pi_list *next;
++ struct port_info *pi;
++};
++
++/* Called by a thread that enters its quiescent period. */
++void
++_ports_thread_quiescent (struct ports_threadpool *pool,
++ struct ports_thread *thread)
++{
++ struct pi_list *free_list = NULL, *p;
++ assert (valid_color (thread->color));
++
++ pthread_spin_lock (&pool->lock);
++ if (thread->color == pool->color)
++ {
++ pool->old_threads -= 1;
++ pool->young_threads += 1;
++ thread->color = flip_color (thread->color);
++
++ if (pool->old_threads == 0)
++ {
++ free_list = pool->old_objects;
++ flip_generations (pool);
++ }
++ }
++ pthread_spin_unlock (&pool->lock);
++
++ for (p = free_list; p;)
++ {
++ struct pi_list *old = p;
++ p = p->next;
++
++ ports_port_deref (old->pi);
++ free (old);
++ }
++}
++
++/* Called by a thread to leave a thread pool. */
++void
++_ports_thread_offline (struct ports_threadpool *pool,
++ struct ports_thread *thread)
++{
++ assert (valid_color (thread->color));
++
++ retry:
++ pthread_spin_lock (&pool->lock);
++ if (thread->color == pool->color)
++ {
++ pthread_spin_unlock (&pool->lock);
++ _ports_thread_quiescent (pool, thread);
++ goto retry;
++ }
++ thread->color = COLOR_INVALID;
++ pool->young_threads -= 1;
++ pthread_spin_unlock (&pool->lock);
++}
++
++/* Schedule an object for deallocation. */
++void
++_ports_port_deref_deferred (struct port_info *pi)
++{
++ struct ports_threadpool *pool = &pi->bucket->threadpool;
++
++ struct pi_list *pl = malloc (sizeof *pl);
++ if (pl == NULL)
++ return;
++ pl->pi = pi;
++
++ pthread_spin_lock (&pool->lock);
++ pl->next = pool->young_objects;
++ pool->young_objects = pl;
++ if (pool->old_threads == 0)
++ {
++ assert (pool->old_objects == NULL);
++ flip_generations (pool);
++ }
++ pthread_spin_unlock (&pool->lock);
++}
+diff --git a/libports/port-deref-deferred.h b/libports/port-deref-deferred.h
+new file mode 100644
+index 0000000..ec1dd27
+--- /dev/null
++++ b/libports/port-deref-deferred.h
+@@ -0,0 +1,87 @@
++/* Delayed deallocation of port_info objects.
++
++ Copyright (C) 2015 Free Software Foundation, Inc.
++
++ Written by Justus Winter <4winter@informatik.uni-hamburg.de>
++
++ This file is part of the GNU Hurd.
++
++ The GNU Hurd is free software; you can redistribute it and/or
++ modify it under the terms of the GNU General Public License as
++ published by the Free Software Foundation; either version 2, or (at
++ your option) any later version.
++
++ The GNU Hurd is distributed in the hope that it will be useful, but
++ WITHOUT ANY WARRANTY; without even the implied warranty of
++ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
++ General Public License for more details.
++
++ You should have received a copy of the GNU General Public License
++ along with the GNU Hurd. If not, see <http://www.gnu.org/licenses/>. */
++
++#ifndef _HURD_PORTS_DEREF_DEFERRED_
++#define _HURD_PORTS_DEREF_DEFERRED_
++
++/* A list of port_info objects. */
++struct pi_list;
++
++/* We use protected payloads to look up objects without taking a lock.
++ A complication arises if we destroy an object using
++ ports_destroy_right. To avoid payloads from becoming stale (and
++ resulting in invalid memory accesses when being interpreted as
++ pointer), we delay the deallocation of those object until all
++ threads running at the time of the objects destruction are done
++ with whatever they were doing and entered a quiescent period. */
++struct ports_threadpool
++{
++ /* Access to the threadpool object is serialized by this lock. */
++ pthread_spinlock_t lock;
++
++ /* We maintain two sets of objects and threads. Each thread and the
++ threadpool itself has a color. If a thread has the same color as
++ the thread pool, it belongs to the old generation. */
++ unsigned int color;
++
++ /* The number of old threads. When an old thread enters its
++ quiescent period, it decrements OLD_THREADS and flips its color
++ (hence becoming a young thread). */
++ size_t old_threads;
++
++ /* A list of old objects. Once OLD_THREADS drops to zero, they are
++ deallocated, and all young threads and objects become old threads
++ and objects. */
++ struct pi_list *old_objects;
++
++ /* The number of young threads. Any thread joining or leaving the
++ thread group must be a young thread. */
++ size_t young_threads;
++
++ /* The list of young objects. Any object being marked for delayed
++ deallocation is added to this list. */
++ struct pi_list *young_objects;
++};
++
++/* Per-thread state. */
++struct ports_thread
++{
++ unsigned int color;
++};
++
++/* Initialize the thread pool. */
++void _ports_threadpool_init (struct ports_threadpool *);
++
++/* Called by a thread to join a thread pool. */
++void _ports_thread_online (struct ports_threadpool *, struct ports_thread *);
++
++/* Called by a thread that enters its quiescent period. */
++void _ports_thread_quiescent (struct ports_threadpool *, struct ports_thread *);
++
++/* Called by a thread to leave a thread pool. */
++void _ports_thread_offline (struct ports_threadpool *, struct ports_thread *);
++
++struct port_info;
++
++/* Schedule an object for deallocation. */
++void _ports_port_deref_deferred (struct port_info *);
++
++#endif /* _HURD_PORTS_DEREF_DEFERRED_ */
+diff --git a/libports/ports.h b/libports/ports.h
+index f02edb4..9299bc4 100644
+--- a/libports/ports.h
++++ b/libports/ports.h
+@@ -29,6 +29,8 @@
+ #include <pthread.h>
+ #include <refcount.h>
+
++#include "port-deref-deferred.h"
++
+ #ifdef PORTS_DEFINE_EI
+ #define PORTS_EI
+ #else
+@@ -73,6 +75,7 @@ struct port_bucket
+ int rpcs;
+ int flags;
+ int count;
++ struct ports_threadpool threadpool;
+ };
+ /* FLAGS above are the following: */
+ #define PORT_BUCKET_INHIBITED PORTS_INHIBITED
+@@ -262,6 +265,9 @@ ports_lookup_payload (struct port_bucket *bucket,
+ {
+ struct port_info *pi = (struct port_info *) payload;
+
++ if (pi && ! MACH_PORT_VALID (pi->port_right))
++ pi = NULL;
++
+ if (pi && bucket && pi->bucket != bucket)
+ pi = NULL;
+
+diff --git a/libports/reallocate-from-external.c b/libports/reallocate-from-external.c
+index 7205bd9..d0fae1a 100644
+--- a/libports/reallocate-from-external.c
++++ b/libports/reallocate-from-external.c
+@@ -71,6 +71,10 @@ ports_reallocate_from_external (void *portstruct, mach_port_t receive)
+ pthread_mutex_unlock (&_ports_lock);
+ assert_perror (err);
+
++ /* This is an optimization. It may fail. */
++ mach_port_set_protected_payload (mach_task_self (), pi->port_right,
++ (unsigned long) pi);
++
+ mach_port_move_member (mach_task_self (), receive, pi->bucket->portset);
+
+ if (stat.mps_srights)
+diff --git a/libports/reallocate-port.c b/libports/reallocate-port.c
+index cc534eb..4e859a1 100644
+--- a/libports/reallocate-port.c
++++ b/libports/reallocate-port.c
+@@ -59,6 +59,10 @@ ports_reallocate_port (void *portstruct)
+ pthread_mutex_unlock (&_ports_lock);
+ assert_perror (err);
+
++ /* This is an optimization. It may fail. */
++ mach_port_set_protected_payload (mach_task_self (), pi->port_right,
++ (unsigned long) pi);
++
+ err = mach_port_move_member (mach_task_self (), pi->port_right,
+ pi->bucket->portset);
+ assert_perror (err);
+diff --git a/libports/transfer-right.c b/libports/transfer-right.c
+index 776a8d2..64de7f7 100644
+--- a/libports/transfer-right.c
++++ b/libports/transfer-right.c
+@@ -91,6 +91,9 @@ ports_transfer_right (void *tostruct,
+ err = hurd_ihash_add (&topi->bucket->htable, port, topi);
+ pthread_rwlock_unlock (&_ports_htable_lock);
+ assert_perror (err);
++ /* This is an optimization. It may fail. */
++ mach_port_set_protected_payload (mach_task_self (), port,
++ (unsigned long) topi);
+ if (topi->bucket != frompi->bucket)
+ {
+ err = mach_port_move_member (mach_task_self (), port,
+--
+2.1.4
+
diff --git a/debian/patches/series b/debian/patches/series
index 49de301c..f6e0cfc2 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -46,3 +46,5 @@ merge-me-0002-startup-faster-reboots.patch
thomas_term.patch
ajoin.patch
proc_disable_new_task_notifications.patch
+0001-procfs-fix-argument-parsing.patch
+0002-libports-use-protected-payloads-to-optimize-the-obje.patch