When in a userns, tasks can't write to certain sysctl files:
(00.009653) 1: Error (sysctl.c:142): Can't open sysctl kernel/hostname: Permission denied
See inline comments for details on affected namespaces.
Mostly for my own education in what is required to port something to be
userns restorable, I ported the sysctl stuff. A potential concern for this
patch is that copying structures with pointers around is kind of gory. I
did it ad-hoc here, but it may be worth inventing some mechanisms to make
it easier, although I'm not sure what exactly that would look like
(potentially re-using some of the protobuf bits; I'll investigate this more
if it looks helpful when doing the cgroup user namespaces port?).
Another issue is that there is not a great way to return non-fd stuff in
memory right now from userns_call; one of the little hacks in this code
would be "simplified" if we invented a way to do this.
v2: coalesce the individual struct sysctl_req requests into one big
sysctl_userns_req that is in a contiguous region of memory so that we
can pass it via userns_call. Hopefully nobody finds my little ascii
diagram too offensive :)
v3: use the fork/setns trick to change the syctl values in the right ns for
IPC/UTS nses; see inline comment for details
v4: only use sysctl_userns_req when actually doing a userns_call.
Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
CID 73377: Resource leak (RESOURCE_LEAK)
10. leaked_storage: Variable values going out of scope leaks the storage
it points to.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We want to have buffered images to speed up dump and,
slightly, restore. Right now we use plan file descriptors
to write and read images to/from. Making them buffered
cannot be gracefully done on plain fds, so introduce
a new class.
This will also help if (when?) we will want to do more
complex changes with images, e.g. store them all in one
file or send them directly to the network.
For now the cr_img just contains one int _fd variable.
This patch chages the prototype of open_image() to
return struct cr_img *, pb_(read|write)* to accept one
and fixes the compilation of the rest of the code :)
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Since we're going to switch from int-fd-s to class-image
soon the fdset name will not fit into the new terminology.
This patch is
sed -e 's/fdset/imgset/g' -i *
sed -e 's/imgset_fd/img_from_set/g' -i *
git mv include/fdset.h include/imgset.h
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Because setting of auto_msgmni recalculates a value of msgmni
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We are going to replace pid on id in names of image files. The id is
uniq for each namespace, so it's more convient, if image files are
opened per namespace.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We should zeroify all data actually for security
reason but this aspect will be addressed in further
patches.
Meanwhile at least allocate enought space so pb_write
won't access data which is not allocated for us.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We have generic do_pb_show() call and tons of show_foo
routines, that just call one with proper args. Compact
the code by putting the args into array and calling
the do_pb_show() in one place.
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>
==22653== Syscall param read(buf) points to unaddressable byte(s)
==22653== at 0x50480B0: __read_nocancel (in /usr/lib64/libpthread-2.17.so)
==22653== by 0x40CF7C: parasite_dump_pages_seized (mem.c:244)
==22653== by 0x41681D: cr_dump_tasks (cr-dump.c:1533)
==22653== by 0x40448C: main (crtools.c:309)
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This will be needed for fast parsing of procfs ns references.
[ xemul: Add user_ns_desc here ]
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
All this sits under config option, so we shouldn't try
to read/write them in this case. What to do if they are
in different on/off state on src/dst kernels is an open
question :\
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
ipc_ns.c:464:3: warning: Memory is never released; potential leak of
memory pointed to by 'values'
return;
^
1 warning generated.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This part was lost after update to "sysctl" interface for IPC object ID
specifying (previous, currently obsolete, interface was able to pass proper
credentials with KEY change) .
Signed-off-by: Stanislav Kinsbursky <skinsbursky@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This patch replaces the format specifier %ld with PRIx64
in the following places:
* the format string argument of the functions scanf() and printf(),
* in the macros GEN_SYSCTL_*_FUNC.
We need explicit specification of the integer size there.
Signed-off-by: Alexander Kartashov <alekskartashov@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
These are structs that (now) tie together ns string
and the CLONE_ flag. It's nice to have one (some code
becomes simpler) and will help us with auto-namespaces
detection.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
IPC shared memory data is aligned by 32 bits.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Old interface with modified IPC syscalls is deprecated is replaced sy sysctls.
This patch updates CRIU to use new interface.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
According to Andrew's advice, change the close file logic a bit, to
make the code seems more readable.
Signed-off-by: Huang Qiang <h.huangqiang@huawei.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Many image files opened by open_image_ro weren't closed before return, fix
them all in this patch.
Signed-off-by: Huang Qiang <h.huangqiang@huawei.com>
Acked-by: Andrew Vagin <avagin@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
CC ipc_ns.o
ipc_ns.c: In function ‘dump_ipc_msg’:
ipc_ns.c:240:2: error: ‘message’ may be used uninitialized in this function [-Werror=uninitialized]
ipc_ns.c:192:17: note: ‘message’ was declared here
cc1: all warnings being treated as errors
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
The pb_read thing is no longer a macros. This will allow to
factor out objects collecting on restore.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This will be required for parasite transport socket creation -- it will
have to be created in a net ns we're putting parasite in and then we'll
have to restore it back to original to go on dumping.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Each fdset item now has the callback which will show a contents of a magic-described
image file. Per-task and global show code is reworked to walk the respective fdsets
and calling ->show on each file.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Due to code sharing, especially in IPC area,
the unbinding is done via helper macros and
sysclt engine tuning (new CTL_SHOW action
added).
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
