Since AIO ring is never pre-dumped, it never has a parent
in pre-dump. Make generate_iovs() to know this.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Description:

1)Create io context, submit several io operations and
get events of some of them.

2)Sleep on signal.

3)Check tail, head and nr events restored correct.

4)Emit one more io operation.

5)Check tail has moved one number forward (i.e. synchronize
in-kernel and userspace tails if they were different).
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Check nr in aio header during dump and correctness of
tail, head and nr during restore.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

1)Dump/restore mmaped aio ring like any other private vma entry,
  with the only exception we do not predump it.
2)Create io context, set head and tail using write to /dev/null.
3)Copy aio ring restored in (1) to created in (2).
4)Remap (2) to address of (1).
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Move the declaration from .c to header file.
Also rename parasite_check_aios() since we
have one more function with the same name.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

The page server already knows how to create a TCP server and client. The
code has been hidden behind static-s in page-xfer.c. This commit moves
the common TCP server/client code to util.c to be able to also use it
in the upcoming remote lazy-server/lazy-client userfaultfd enhanced criu.
Signed-off-by: Adrian Reber <areber@redhat.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Signed-off-by: Andrew Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Impact: no functional changes, cleanup.
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Impact: no functional changes, cleanup.
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Impact: no functional changes, cleanup
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Add checks that structure end is inside memory area [mem, mem + size]
before dereferencing structures.
Otherwise, for example, vdso_fill_symtable will try to dereference
ehdr members even with vma size 0.
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Impact: drop additional casts all around. Cleanup.
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Impact: refactor
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

As I am here to fix some things, I would like to remove UB-based
pointer compare (6.5.8.5). We have -fno-strict-aliasing in pie
CFLAGS, but it even looks nicer and more readable with uintptr_t.

Impact: refactoring
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Add Elf32 types and wrap them with Elf64 into some more generic types.
This is for parsing vDSO from image file.
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Right now we get SOL_TCP.TCP_INFO option twice, but one time
is enough.
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

This is prerequisite for the next patch and, actually, for the libsoccr :)
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Parasite should cleanup after fauilure and remove read-protection
from VMAs. Check it with maps00 test & fault injection.

Tested on travis with some addition:
python test/zdtm.py run -t zdtm/static/maps00 --fault 3 --keep-going --report report -f h || false
https://travis-ci.org/0x7f454c46/criu/jobs/119252291

Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

It's just a cleanup to get rid of in-function {<code>} block.
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

By default criu tries to create parasite mem with memfd syscall,
which is present in many systems. Let's check also the legacy way.
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

The plan is to allow ->collect callbacks to read more
stuff from image files.
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

With autofs patches we've merged a small engine that allows
to queue random routine for post-prepare execution. Re-use
this for unix sockets' interconneting routine.

Also this is a tiny optimization -- when we don't have unix
sockets to interconnect we don't make extra list walk.
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Consider when there is a double fork of helpers or zombies, e.g. when a
zombie has a session id which doesn't match its pid. If the child dies and
exits before the grandchild, the grandchild reparents to init, and when the
task dies init doesn't have it in the helper list, so init dies as well,
viz. the log below.

(00.118789) Add a helper 293 for restoring SID 293
(00.118792) Attach 294 to the temporary task 293
...
(01.394403)    294: Restoring zombie with 0 code
...
pie: Task 294  exited, status= 0
(01.434279) Error (cr-restore.c:1308): 12097 killed by signal 19
(01.434420) Error (cr-restore.c:1308): 12097 killed by signal 19
(01.450258) Switching to new ns to clean ghosts
(01.450324) Error (cr-restore.c:2138): Restoring FAILED.

Let's have the helpers reap their children before they exit to avoid this.

v2: block SIGCHLD when waiting on helpers so that it doesn't race with the
    SICGHLD handler
v3: * only helpers should collect their children, zombies can't have kids
    * don't double decrement nr_tasks in zombie case
Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

The following error happens when building CRIU on Fedora 22:

  CC       autofs.o
autofs.c: In function ‘autofs_mount’:
autofs.c:892:9: error: implicit declaration of function ‘add_post_prepare_cb’ [-Werror=implicit-function-declaration]
   ret = add_post_prepare_cb(autofs_add_mount_info, mi);
         ^
cc1: all warnings being treated as errors

Adding forward declaration of add_post_prepare_cb resolves the issue.
Signed-off-by: Mike Rapoport <rapoport@il.ibm.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Signed-off-by: Stanislav Kinsburskiy <skinsbursky@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Autofs restore needs to create some shared data structures to be able to pass
data to actual autofs master.
But on mount restore stage shared data is not configured yet.
This list of objects and their actors is processed after all mounts and shared
data are restored to let autofs to create the objects.
Signed-off-by: Stanislav Kinsburskiy <skinsbursky@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Before the nsroot= mount option, we were just getting lucky because the
cgroup superblocks "matched" when inspecting them from userspace, so we
were actually getting a bind mount from the host when migrating from within
cgroup namespaces.

Instead, let's actually do a new (i.e. not a bind mount) for cgroup
namespaces. For this, we need two things:

1. to prepare the cgroup namespace (and thus the cgroups) before the mount
   ns, so when the mount() occurrs it is relative to the right cgroup path.

2. not reject cgroup filesystems with no root. A cgroup ns mount looks
   like:

	 223 222 0:22 /lxc/unpriv /sys/fs/cgroup/systemd rw,nosuid,nodev,noexec,relatime - cgroup cgroup rw,xattr,release_agent=/lib/systemd/systemd-cgroups-agent,name=systemd,nsroot=/lxc/unpriv

   i.e. it has /lxc/unpriv as its root, and thus doesn't look rooted to CRIU.
   We use the fstype->parse hook to rewrite this root to /, since it
   is handled by the cgroup ns infrastructure.

v2: add new fstype->munge hook, allowing fstypes to munge their parsed
    mountinfo entries if they want to. this allows us to get rid of the
    ugly hacks with FSTYPE__CGROUP everywhere in teh patch.
v3: s/fstype->munge/fstype->parse for FSTYPE__CGROUP
Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

The target has been broken for some time without complaints from users.
https://lists.openvz.org/pipermail/criu/2016-March/026525.html

Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

To link dynamic libs (libcompel for example).
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>