To unify the code for both thread leader and regular threads
we move blocked signals for thread leader into threads argument
area and use restore_thread_common() helper.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
I've moved dump_thread helper a bit lower in file
since I've to call for find_thread_state helper.
After all this groups all thread related functions
in one slab.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This patch starts using parasite_init_threads_seized and
parasite_fini_threads_seized helpers to save per-thread
data in parasite and remove it on cure procedure.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Just to be consistent with types we're using.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We will need to extend the structure to keep not only tid/tid_addr
but blocked signals as well, thus rename it to more generic
parasite_dump_thread.
The command PARASITE_CMD_DUMP_TID_ADDR renamed to
PARASITE_CMD_DUMP_THREAD for the same sake.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We will use them from crtools code to save and restore blocked
signals mask of threads.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
These helpers will be needed to save a blocked signals
mask for dumpee threads.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
The per-thread information requires own space in parasite data.
In particular we will keep the blocked signals bound to thread
pids.
For this sake the caller need to provide the parasite how many
threads will be used to calculate space.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Three parts.
Proc: open of map_files' link doesn't work on sockets. We fstatat
it and check that it's a socket (it will be packet), then save
the socket inode on vma_area.
Dump: we resolve socket inode to socket id and save it on vma.
We use id, not inode, since on restore we'll have to mmap some
opened file, not just abstract socket with inode.
Restore: when reading vma-s we just need to find out on what fd
the respective packet socket is opened (i.e. -- no map-and-close
sockets supported by now) and dup() it to let restorer mmap it
back.
All this make it possible to c/r the tcpdump tool!
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Sizes of send and recv buffers are set to maximum to restore queues,
after that sizes of buffers are restored.
O_NONBLOCK is set to a socket to prevent blocking during restore.
#2411
v2: do the same for unix sockets.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Writing to last_pid sysctl is CAP_SYS_ADMIN potected. Thus restoring
creds before it won't work in all the cases.
Fix this by making all threads restore creds themselves, and the
thread group leader -- after all of them.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Andrey Vagin <avagin@parallels.com>
The size of vector depends on the kernel config
so use the real size of a vector dumped. Otherwise
we might fail on restore.
Reported-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
The former is actually the parameters of thread group leader, so
it's natural to have them on-task.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
The dumping of tty peers is somewhat tricky. And it became more
complex once we allowed to migrate/inherit sessions.
It's being found (in screen c/r) that we've a problem in looking
up of session leaders while dumping tty.
Let me explain with more details. Here is an example of screen
session
PID GID SID
20567 20567 20567 SCREEN
20568 20568 20568 pts/3 \_ /bin/bash
The screen opens master peer (ptmx) and then provides
bash the slave peer (pts/3) where bash sets up a session
leader on it.
Thus we get interesting scenario -- our pstree construction
is done in lazy fashion, we run parasite code to fetch sid/pgid
of a process tree item only when we're really dumping the task.
Thus when we start dumping ptmx peer (which belongs to SCREEN)
we've not yet constructed the process tree item for children
(ie /bin/bash) and the lookup function in tty code (which walks
over all process items in a tree) simply fails to find sid of
child, because we've not yet dumped it.
Thus, to resolve such situation we verify tty sids at late stage
of dumping.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
On my testing machine these defs are not present
so define them where needed.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Get the info from kernel diag message (it should always be there)
and restore the shutdown at the very end.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
It will be required to support socket bound to devices.
When restoring w/o net namespaces -- collect existing devices.
When restoring with them -- collect what is received from image.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This option will tells the tool to procceed dumping
even if a root task is not a session leader.
This implies that this option will allow to "migrate"
one external tty connection. Say a person may dump
"top" application in one bash shell and restore it
in another shell session.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We will need it for slave ttys migration. They serve for one purpose --
to clone self stdio descriptor and use it with tty layer, which will
be addressed in further patches.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
It should fit the sa_sigaction declaration, otherwise compiler
complains about uncasted assignments.
| restorer.c: In function тАШ__export_restore_taskтАЩ:
| restorer.c:318:20: error: assignment from incompatible pointer type [-Werror]
So just use siginfo_t here from the system signal.h header.
Signed-off-by: Andrew Grigorev <andrew@ei-grad.ru>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
No magic here, just fetch info using getpriority and sched_getxxx calls.
Good news is that the mentioned syscalls take pid as argument and do work
with it, i.e. -- no need in parasite help here.
Restore is splitted into prep -- copy sched bits from image on restorer
args -- and the restore itself. It's done to avoid restoring tasks info
with IDLE priority ;) To make restorer not-fail sched bits are validated
for sanity on prep stage.
Minimal sanity test is also there.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Some file-type specific parameters can be fetched with
parasite code only, so lets carry parasite control block
pointer in struct fd_parms.
This is a bit ugly but requires less code to touch and
enough for now. In long terms we need some more generalized
routine/hooks which would depends on file type.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Will need it to fetch tty link parameters. This is
because the kernel provides SID/PGID related to the
caller context, and if we're dumping the process inside
namespace -- we need local SID/PGIDs, not global ones.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
In case if here no task found which would restore
controlling terminal -- exit with error instead of
continue with just error message.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
No need for memcpy here, it's plain integer value
which need to be filled.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Dumping them is performed via parasite, since calling the getgroups
is the only way of getting the complete list. Currently the nr of
groups to dump is limited explicitly with the size of shared memory
between crtools and parasite. This is MUCH more that we have seen
on real apps so far.
Restoring is done early, before restorer blob not to carry the undefined
array of grpous in there. This is OK, since groups do not affect us at
that point and are not affected by subsequent creds restore.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Getting groups can be done vie proc, but there's only 32 on them,
while task may have up to 65k :( We will use parasite for that and
thus require this syscall definition.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Currently move there the secbits dumping, which is not dumped
via misc-dumping command. This patch is required to support
per-task groups dumping (setgroups/getgroups) -- we'll have to
drain the groups from parasite.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
I believe this make sense to keep this structure
in pstree.h where pstree related data lives.
Also I've added some comments on struct pid members.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
- @list member closer to @children
- add some comments on memebers
- add space lines for members grouping
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Remove the restorer-log and link log-simple into restorer
blob. Now we can use the normal pr_foo API.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
It's supposed to be used by parasite and restorer blob. It
has API equal to the core one -- with setfd, set_loglevel and
(the main thing) print_on_level fn. It currently supports only
strings, decimal and hex numbers (int and long).
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
It reads /proc/PID/fd and close all descriptors except service fds.
v2: s/is_one_of_service_fds/is_any_service_fd
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
For executing an external tools we need to block a SIGCHLD
and to juggle file descriptors.
SIGCHLD is blocked for getting an exit code.
A problem with file descriptors can be if we want to set 2 to STDIN,
1 to STDERR, 0 to STDOUT for example.
v2: use helpers reopen_fd_as and move_img_fd
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
By default crtools shouldn't modify the environment, except for
killing the dumped tasks. The link remap does so and should sit
under explicit cmdline option.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
These are not ghost, as they are still on fs, so we cannot take
them with us in the image. Neither we can easily find the other name
of that file. Sad :(
To make it work we linkat() the new name to that file using the
AT_EMPTY_PATH flag to link directly to the opened fd. If we could
openat() the fd's parent we would better do it, but we can't and
thus have to create the link name by explicit absolute path :(
This modifies the fs we're dumping, so I'll introduce one more cmd
line option for that soon.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
For linked remaps we'll use similar technique as for ghost
files, but lighter. For that sake make reg_file_info remap
to file_remap, not to the whole host_file.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
