For paths resolution we will need mount tree to be parsed
and built, but it's not that simple -- the current code
implies that once parsed the tree must not be re-parsed
again, so we pass @parse argument from a caller: if a task
we're restoring do not use mount namespace, we should parse
mount tree early, otherwise defer this action until mount
tree is read from the image.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
In case if checkpoint is failed or -R option passed
we need to remove link remap files created during
dump procedure.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
It's been found that if -R (leave task running after checkpoint)
option passed we don't unlock network, nether we clean service
files (such as link remaps).
After a long discussion we choose the following path: if -R option
is passed, it means a user is quite confident in what he is doing
and consistency of the resources (file system) is achieved by
a user himself with help of post-dump script. Also a user knows
that the network will be unlocked and accept such case.
So here we check of -R being passed in command line and once
checkpoint complete we unlock the network.
Cleaning up of link remaps is addressed in another patch.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Don't carry it around in a static global variable. Would
be useful for pidns leaks (processes entered one) scan.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
It's not enough to check only uids on dump and restore -- we need to
check e-ids and s-ids now (and caps in the future).
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
When dump/pre-dump failed before initializing vmas, free_mappings(&vmas)
is called and this cause segfault. Lets initialize vmas in the very
beginning of dump.
Signed-off-by: Ruslan Kuprieiev <kurpuser@gmail.com>
seqfault.patch
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Right now we have an ability to launch the C/R service from root
and execure dump requests from unpriviledged users. Not to be bad
guys, we deny dumping tasks belonging to user, that cannot be
"watched" (traced, read /proc, etc.) by the dumper.
In the future we will use this "engine" when launched with suid
bit, and (probably) will have more sophisticated policy.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Currently we catch processes on the exit point from sigreturn.
If a task must be restored in the stopped state, we can send SIGSTOP
before detaching from it.
v2: add more descriptive comment about skipping SIGSTOP in ptrace.c
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Currently we take pid and core from it and we are going to take state.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
parse_thread allocated a buffer for threads and then it initialized read
pid for each thread.
Now we want to use it on restore and in this moment we already have
a buffer with initialized virt pid-s, so we need to initialize read
pid-s only.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
It will be used in cr-restore.c for stopping threads on the exit from
sigreturn.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This is for security -- service is run from root, but serves requests from non-root
processes. Thus, we shouldn't allow for anyone to dump suid programs that a run from
under unpriviledged processes.
Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
These contain linkage between number, data type and routines
for pb messages we write/read to/from image files. Most of them
have simple number-type-routines mapping, so introduce a generating
script for that.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Restore stats are difficult -- we have to collect them from several
tasks and thus existing plain variables would not work. We'll need
shared memory with stats, so prepre for allocating one.
Other than this -- put call to write_stats() where appropriate for
restore.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Currently criu sends data to the page server, but it doesn't get any
feedback, so it can't be sure that all data have been accepted.
This patch adds a flush command, which requires an answer from the page
server. This command is sent before disconnecting.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This is usefull if one needs to do some final action before checkpoint
is complete. For example in case of online migration one may provide
a script which would check the restore procedure on remote note
ended without errors, thus the script returns zero code and criu
simply kills running instance of application.
In turn, if migration failed, the script can return nonzero code
and criu won't kill the application but continue its execution
instead.
https://bugzilla.openvz.org/show_bug.cgi?id=2583
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
There are parts dumping which is common to thread and task,
and this stuff is represented by parasite_dump_thread structure.
Merge this into parasite_dump_misc and facror out dumping code.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
The initilization stage is not good for that, because it can fail.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Otherwise we lost 1:1 mapping between names being
dumped and what user sees after restore.
| 1455 pts/0 T 0:00 \_ ./crtools restore -t 1448
| 1448 ? Ss 0:00 | \_ ./zombie00 --pidfile=zombie00.pid --outfile=zombie00.out
| 1449 ? Z 0:00 | \_ [zombie00] <defunct>
| 1450 ? Z 0:00 | \_ [zombie00] <defunct>
| 1451 ? Z 0:00 | \_ [zombie00] <defunct>
| 1452 ? Z 0:00 | \_ [zombie00] <defunct>
https://bugzilla.openvz.org/show_bug.cgi?id=2635
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Andrew Vagin <avagin@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This mask should be put into sigframe (used by parasite, coming
soon) thus we have to pull one from dumpee early.
Plus, check that signals are blocked for each thread separately
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Otherwise a task can start to handle a signal and registers can be
changed.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Currently it's always stopped, but it will be changed, when a parasite
will be executed as a daemon.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We have three arrays for thread related data: item->threads,
parasite_ctl->thread and tid_state in parasite.
With this patch a thread will have the same index in all arrays.
The zero index is used for a thread leader.
In this case we don't need to search thread_state in parasite.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
When parasite daemon mode will be implemented we get deprived of ability
to fetch registers at the late moment of dumping as we were, thus just
bind CoreEntry to pstree item and allocate CoreEntry'ies for every
thread found, once process tree is in seized state.
Then immediately fill CoreEntry'ies with registers. We use prctl
opcode for that but fetch a complete set of registers including
FPU state, and convert them into protobuf format.
Zombie tasks remains untouched, we allocate CoreEntry for them
right at moment of dumping becuase we don't need registers there
to be written on disk.
This way get_task_regs no longer need parasite_ctl argument
and it's zapped.
Still parasite_ctl has own copy of general registers set but
this is because we need them to be in cpu native format unlike
ones kept in CoreEntry.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
In case if we have created vdso proxy the rt-vdso should
not be dumped because it will be re-created on next restore
anyway. Thus with help of parasite service routine find
the rt-vdso and tear it off from VMAs list.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
During criu startup we need to fill symbol table of own
run-time vdso provided by the kernel. We will need this
data for vdso proxy.
Because this functions are not used in restorer code,
we move them out of PIE (since PIE code must remain
as small as possible).
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
When a kernel didn't show vma flags, we set MAP_GROWSDOWN for stack
vmas, but it's not reliable. E.g. thread stacks are mapped without
MAP_GROWSDOWN.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
struct fd_parms is reused for two calls, so don't
forget to initialize it before dump_one_reg_file
call.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
With this action criu will seize tasks, grab all its memory into
page-pipes, rest dirty tracker and will then release them. Writing
the memory from page-pipes would occur after tasks are unfreezed
and thus the frozen time should become reasonably small.
When pre-dump is in action, the dirty tracking is forcedly turned
off as well as tasks are resumed afterwards, not killed, by default.
This is a prerequisite for iterative migration.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
