musl-libc fixed inconsistency between posix and kernl msghdr structures
by adding pad-s.
It initializes all pad-s before calling recvmsg and sendmsg syscalls.
CRIU calls raw system calls from pie code, so we need to intialize pads too.
In addition, we don't initialize msg_flags and iov_len.
https://github.com/xemul/criu/issues/276https://travis-ci.org/kolyshkin/criu/builds/198415449
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
C compiler might generate calls to memcpy, memset, memcmp, and memmove
as it seem fit (so far we haven't seen memmove being required). That
means we need to provide our own versions of it for code which is not
linked to a libc.
We already have a solution for that in commit bdf6051
("pie: provide memcpy/memcmp/memset for noglibc case")
but we faced another problem of compiler trying to optimize
our builtin_memset() by inserting calls to memset() which
is just an alias in our case and so it lead to infinite recursion.
This was workarounded in commit 8ea0ba7 ("string.h: fix memset
over-optimization with clang") but it's not clear that was a proper
fix.
This patch is considered to be the real solution. As we don't have
any other implementations of memset/memcpy/memcmp in non-libc case,
we can call ours without any prefixes and avoid using weak aliases.
Implementation notes:
1. mem*() functions code had to be moved from .h to .c for the functions
to be compatible with their prototypes declared in /usr/include/string.h
(i.e. "extern").
2. FORTIFY_SOURCE needed to be disabled for code not linked to libc,
because otherwise memcpy() may be replaced with a macro that expands
to __memcpy_chk() which of course can't be resolved during linking.
https://travis-ci.org/kolyshkin/criu/builds/198415449
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
This will be used to pass MSG_DONTWAIT in next patch.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Replace "-1" return with errno codes.
ENOMSG and EBADFD were choosen to do not cross with
standard recvmsg() errors (described in its man page).
This patch is need as preparation to making recv_msg()
be able to be non-block, and return EAGAIN and EWOULDBLOCK
in case of no data.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Remove getting opts from descriptors out from scm engine,
this stuff is pure criu thing, so make it collect the data.
The tricky change here is that parasite code needs memory
to keep fd_opts on. The memory is taken from parasite args
region, which is now bigger than it used to be. But that's
not a big deal, as previously this space was allocated on
the parasite stack (!, but with smaller chunks).
On the other hand, now we have one memcpy less, as opts are
put directly into the destination buffer.
travis-ci: success for files: Rework send/recv-fds to be more generic
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
When SCM_FDSET_HAS_OPTS is not set the scm-code.c
can't be built because it declares struct fd_opts
in parameters. Lets rather hide this type and
allow to build without SCM_FDSET_HAS_OPTS definition.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
In pure-compel library messing with opts is not required,
only criu and criu's pie will need it, so make it possible
to compile out common/scm-code's opts management.
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
