maps007 segfaults on i386, because "size" is calculated bigger than allowed.

This occurs when the result of lrand48() * PAGE_SIZE is negative.
In this case the % operation returns a negative value too, what is unexpected.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

So, according to the recently accepted plan we have 1.4.

Biggest achievement here is that we've finally started with
user namespaces, fixed CRIU to work smoothly with the p.haul
project and optimized images and /proc files IO.

And a bunch of bugs, of course.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

When we generate a path to the previous images, we take a directory name
and the previous iteration number.

Reported-by: Mr Jenkins
Signed-off-by: Andrew Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

We see big load-avarage for the CRIU-iter job, because the host is
writing images for the maps04 test. If we will remove images after retore,
they will live in a page cache. Curretly we collect images for three
iterations and their size is too big to live in a cache.

[root@jenkins workspace]# time bash test/zdtm.sh  -i 3 ns/static/maps04
real	2m23.765s
user	0m0.719s
sys	0m4.006s
[root@jenkins workspace]# time bash test/zdtm.sh -C -i 3 ns/static/maps04
real	1m34.884s
user	0m0.200s
sys	0m4.191s
Signed-off-by: Andrew Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Currently ns/test and test may have the same test directory,
especially if zdtm.sh is executed with --ct.

Reported-by: Mr Jenkins
Signed-off-by: Andrew Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

32 is too many for our test server
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

CID 83243 (#1 of 1): Resource leak (RESOURCE_LEAK)
6. leaked_handle: Handle variable fd going out of scope leaks the handle.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

When we are doing pre-dump, we splice pages in pipes and only then open
images and dump pages. But when we are splicing pages, we need to know
about existence of parent images. This patch adds a new call to determin
existence of parent images.

In addition this patch fixes a following issue:
CID 83244 (#1 of 1): Uninitialized pointer read (UNINIT)
14. uninit_use: Using uninitialized value xfer.parent.

v2: initialize unused field of struct page_server_iov, because it sends
in network.

CID 83451 (#1 of 1): Uninitialized scalar variable (UNINIT)
2. uninit_use_in_call: Using uninitialized value pi. Field pi.nr_pages
is uninitialized when calling write.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

For stream sockets it's possiable and we should not fail in this case.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

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

Need to print a mask of events for UNKNOWN event in inotify_system_nodel.c
and inotify_system.c tests. The current error message in this case is too vague:
inotify_system_nodel.c:266: got unexpected event UNKNOWN
Signed-off-by: vkonyashkin <vkonyashkin@parallels.com>
Acked-by: Andrew Vagin <avagin@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

It is in mainline and required for proper CRIU work.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

And move the 2nd piece lower to avoid fwd declaration and
keep similar calls close to each other.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Reported-by: Mr Jenkins
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Here is an example from a fedora container:
65 64 252:0 /vz/private/1 / rw,relatime shared:29 - ext4 /dev/mapper/centos_pcs-root rw,data=ordered
77 65 252:0 /vz/private/1/var/tmp/systemd-httpd.service-XLnJPNc/tmp /var/tmp rw,relatime shared:41 - ext4 /dev/mapper/centos_pcs-root rw,data=ordered

We can see non-root shared mount, which is mounted to the root
mount from the same shared group. The test emulates this situation.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Fedora bind-mounts a part of the root mount to itself. Currently we
don't allow to mount children of a shared mount, if other mount from
this shared group are not mounted.

This patch adds an exclusion for cases, when a child has the same
group. We allow to mount a child, if wider mounts are mounted.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Currently we connect roots of sub-namespaces to the root of the root
mount namespace. And we get problems, if the root of the root mntns is
shared, because all children of a shared mount must be propagated to
other mounts in this group.

Actually we mount tmpfs in mnt_roots and here is nothing wrong to add it
in a tree.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

And use the expression for it, it's quite short. This
makes the amount of variables in the code fit into brains.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Andrew Vagin <avagin@parallels.com>

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

Do paths conversions and checks step-by-step and add many comments
what we do in each step and why.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Andrew Vagin <avagin@parallels.com>

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

When we check whether a submount of a mount is visible in another
mount (shared peer of the latter), we can and should use the new
issubpath helper.

Should because the used strncmp may scan beyond ct_mpnt_rpath if
its length is smaller (no checks for this in the code).
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Andrew Vagin <avagin@parallels.com>

These are constant for given m, so calculate them outside
of the loop. Also rename them to reflect what they are.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Andrew Vagin <avagin@parallels.com>

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

The path lenght is zero for the "/" one and strlen(path)
for all the others. This is done so to make it possible
to use this length to get tail-paths: if path_1 starts
with path_2 and both are absolute, then

   path_1 + path_length(path_2)

would give the tail of the tail of path_1 relative to
path_2 even if the path_2 is just "/".
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Andrew Vagin <avagin@parallels.com>

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

A problem which is solved in this path is that some children can be
unaccessiable (unvisiable) for non-root bind-mounts

root	mount point
-------------------
/	/a (shared:1)
/	/a/x
/	/a/x/y
/	/a/z
/x	/b (shared:1)
/	/b/y

/b is a non-root bind-mount of /a
/y is visiable to both mounts
/z is vidiable only for /a

Before this patch we checked that the set of children is the same for
all mount in a shared group. Now we check that a visiable set of mounts
is the same for all mounts in a shared group.

Now we take the next mount in the shared group, which is wider or equal
to current and compare children between them.

Before this patch validate_shared(m) validates the m->parent mount.
Now it validates the "m" mount. So you can find following lines in the
patch:
-               if (m->parent->shared_id && validate_shared(m))
+               if (m->shared_id && validate_shared(m))

We doesn't support shared mounts with different set of children.
Here is an example of such case can be created:
mount tmpfs a /a
mount --make-shared /a
mkdir /a/b
mount tmpfs b /a/b
mount --bind /a /c

In this case /c doesn't have the /b child. To support such cases,
we need to sort all shared mounts accoding with a set of children.

v2: If root is equal to "/", its len should be zero. We expect that the
last symbol in a path is not "/".
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

expr ns/user/static/env00 ns/user
expr: syntax error
Signed-off-by: Andrew Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

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

Make their name look similar.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

We have sanity check for zombie-with kids below, no
need in additional.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

We scan threads and children list several times while freezing
the tree, this is done to avoid race with new threads/kids
appearing.

Factor out the iterations code.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

To make the threads collect code be structured similar to
children collect. This will also help in further patching.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

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

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

Keeping the whole stat buf it too much information.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

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