We have seen an issue on s390x platform where domain XMLs larger than 1MB
were used. The define command was finished successfully. The dumpxml command
was not successful (i.e. could not encode message payload).
Enlarged message related sizes (e.g. maximum string size, message size, etc.)
to handle larger system configurations used on s390x platform.
To improve handling of the RPC message size the allocation during encode process
is changed to a dynamic one (i.e. starting with 64kB initial size and increasing
that size in steps up to 16MB if the payload data is larger).
Signed-off-by: Daniel Hansel <daniel.hansel@linux.vnet.ibm.com>
Signed-off-by: Viktor Mihajlovski <mihajlov@linux.vnet.ibm.com>
A number of bugs handling file descriptors received from the
server caused the FDs to be lost and leaked.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
On OOM, xdr_destroy got called even though it wasn't created yet.
Found by coverity:
Error: UNINIT (CWE-457):
libvirt-0.10.2/src/rpc/virnetmessage.c:214: var_decl: Declaring
variable "xdr" without initializer.
libvirt-0.10.2/src/rpc/virnetmessage.c:219: cond_true: Condition
"virReallocN(&msg->buffer, 1UL /* sizeof (*msg->buffer) */,
msg->bufferLength) < 0", taking true branch
libvirt-0.10.2/src/rpc/virnetmessage.c:221: goto: Jumping to label
"cleanup"
libvirt-0.10.2/src/rpc/virnetmessage.c:257: label: Reached label
"cleanup"
libvirt-0.10.2/src/rpc/virnetmessage.c:258: uninit_use: Using
uninitialized value "xdr.x_ops".
https://www.gnu.org/licenses/gpl-howto.html recommends that
the 'If not, see <url>.' phrase be a separate sentence.
* tests/securityselinuxhelper.c: Remove doubled line.
* tests/securityselinuxtest.c: Likewise.
* globally: s/; If/. If/
Per the FSF address could be changed from time to time, and GNU
recommends the following now: (http://www.gnu.org/licenses/gpl-howto.html)
You should have received a copy of the GNU General Public License
along with Foobar. If not, see <http://www.gnu.org/licenses/>.
This patch removes the explicit FSF address, and uses above instead
(of course, with inserting 'Lesser' before 'General').
Except a bunch of files for security driver, all others are changed
automatically, the copyright for securify files are not complete,
that's why to do it manually:
src/security/security_selinux.h
src/security/security_driver.h
src/security/security_selinux.c
src/security/security_apparmor.h
src/security/security_apparmor.c
src/security/security_driver.c
My latest patch for RPC rework (a2c304f687) introduced a memory leak.
virNetMessageEncodeHeader() is calling VIR_ALLOC_N(msg->buffer, ...)
despite fact, that msg->buffer isn't VIR_FREE()'d on all paths calling
the function. Therefore, rather than injecting free statement switch to
VIR_REALLOC_N().
Currently, we are allocating buffer for RPC messages statically.
This is not such pain when RPC limits are small. However, if we want
ever to increase those limits, we need to allocate buffer dynamically,
based on RPC message len (= the first 4 bytes). Therefore we will
decrease our mem usage in most cases and still be flexible enough in
corner cases.
Our HACKING discourages use of malloc and free, for at least
a couple of years now. But we weren't enforcing it, until now :)
For now, I've exempted python and tests, and will clean those up
in subsequent patches. Examples should be permanently exempt,
since anyone copying our examples won't have use of our
internal-only memory.h via libvirt_util.la.
* cfg.mk (sc_prohibit_raw_allocation): New rule.
(exclude_file_name_regexp--sc_prohibit_raw_allocation): and
exemptions.
* src/cpu/cpu.c (cpuDataFree): Avoid false positive.
* src/conf/network_conf.c (virNetworkDNSSrvDefParseXML): Fix
offenders.
* src/libxl/libxl_conf.c (libxlMakeDomBuildInfo, libxlMakeVfb)
(libxlMakeDeviceModelInfo): Likewise.
* src/rpc/virnetmessage.c (virNetMessageSaveError): Likewise.
* tools/virsh.c (_vshMalloc, _vshCalloc): Likewise.
Define two new RPC message types VIR_NET_CALL_WITH_FDS and
VIR_NET_REPLY_WITH_FDS. These message types are equivalent
to VIR_NET_CALL and VIR_NET_REPLY, except that between the
message header, and payload there is a 32-bit integer field
specifying how many file descriptors have been passed.
The actual file descriptors are sent/recv'd out of band.
* src/rpc/virnetmessage.c, src/rpc/virnetmessage.h,
src/libvirt_private.syms: Add support for handling
passed file descriptors
* src/rpc/virnetprotocol.x: Extend protocol for FD
passing
Commit 2c85644b0b attempted to
fix a problem with tracking RPC messages from streams by doing
- if (msg->header.type == VIR_NET_REPLY) {
+ if (msg->header.type == VIR_NET_REPLY ||
+ (msg->header.type == VIR_NET_STREAM &&
+ msg->header.status != VIR_NET_CONTINUE)) {
client->nrequests--;
In other words any stream packet, with status NET_OK or NET_ERROR
would cause nrequests to be decremented. This is great if the
packet from from a synchronous virStreamFinish or virStreamAbort
API call, but wildly wrong if from a server initiated abort.
The latter resulted in 'nrequests' being decremented below zero.
This then causes all I/O for that client to be stopped.
Instead of trying to infer whether we need to decrement the
nrequests field, from the message type/status, introduce an
explicit 'bool tracked' field to mark whether the virNetMessagePtr
object is subject to tracking.
Also add a virNetMessageClear function to allow a message
contents to be cleared out, without adversely impacting the
'tracked' field as a naive memset() would do
* src/rpc/virnetmessage.c, src/rpc/virnetmessage.h: Add
a 'bool tracked' field and virNetMessageClear() API
* daemon/remote.c, daemon/stream.c, src/rpc/virnetclientprogram.c,
src/rpc/virnetclientstream.c, src/rpc/virnetserverclient.c,
src/rpc/virnetserverprogram.c: Switch over to use
virNetMessageClear() and pass in the 'bool tracked' value
when creating messages.
Improve log messages issued when encountering a bogus
message length to include the actual length and the
limit violated
* src/rpc/virnetmessage.c: Improve log messages
On stream completion it is neccessary to send back a
message with an empty payload. The message header was
not being filled out correctly, since we were not writing
any payload. Add a method for encoding an empty payload
which updates the message headers correctly.
* src/rpc/virnetmessage.c, src/rpc/virnetmessage.h: Add
a virNetMessageEncodePayloadEmpty method
* src/rpc/virnetserverprogram.c: Write empty payload on
stream completion
This guts the libvirtd daemon, removing all its networking and
RPC handling code. Instead it calls out to the new virServerPtr
APIs for all its RPC & networking work
As a fallout all libvirtd daemon error reporting now takes place
via the normal internal error reporting APIs. There is no need
to call separate error reporting APIs in RPC code, nor should
code use VIR_WARN/VIR_ERROR for reporting fatal problems anymore.
* daemon/qemu_dispatch_*.h, daemon/remote_dispatch_*.h: Remove
old generated dispatcher code
* daemon/qemu_dispatch.h, daemon/remote_dispatch.h: New dispatch
code
* daemon/dispatch.c, daemon/dispatch.h: Remove obsoleted code
* daemon/remote.c, daemon/remote.h: Rewrite for new dispatch
APIs
* daemon/libvirtd.c, daemon/libvirtd.h: Remove all networking
code
* daemon/stream.c, daemon/stream.h: Update for new APIs
* daemon/Makefile.am: Link to libvirt-net-rpc-server.la
This provides a new struct that contains a buffer for the RPC
message header+payload, as well as a decoded copy of the message
header. There is an API for applying a XDR encoding & decoding
of the message headers and payloads. There are also APIs for
maintaining a simple FIFO queue of message instances.
Expected usage scenarios are:
To send a message
msg = virNetMessageNew()
...fill in msg->header fields..
virNetMessageEncodeHeader(msg)
...loook at msg->header fields to determine payload filter
virNetMessageEncodePayload(msg, xdrfilter, data)
...send msg->bufferLength worth of data from buffer
To receive a message
msg = virNetMessageNew()
...read VIR_NET_MESSAGE_LEN_MAX of data into buffer
virNetMessageDecodeLength(msg)
...read msg->bufferLength-msg->bufferOffset of data into buffer
virNetMessageDecodeHeader(msg)
...look at msg->header fields to determine payload filter
virNetMessageDecodePayload(msg, xdrfilter, data)
...run payload processor
* src/Makefile.am: Add to libvirt-net-rpc.la
* src/rpc/virnetmessage.c, src/rpc/virnetmessage.h: Internal
message handling API.
* testutils.c, testutils.h: Helper for printing binary differences
* virnetmessagetest.c: Validate all XDR encoding/decoding
