Commit Graph

15 Commits

Author SHA1 Message Date
Olaf Hering 269ce62bbc Tools: hv: use single send+recv buffer
send_buffer is used only once during registration. To reduce runtime
memory usage reuse the recv_buffer for registration. Also use
NLMSG_LENGTH instead of NLMSG_HDRLEN to take alignment into account.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-09-26 12:03:31 -07:00
Olaf Hering b4fb0ca260 Tools: hv: use full nlmsghdr in netlink_send
There is no need to have a nlmsghdr pointer to another temporary buffer.
Instead use a full struct nlmsghdr.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-12 15:44:57 -07:00
Olaf Hering 2bc41ea3b3 Tools: hv: correct payload size in netlink_send
netlink_send is supposed to send just the cn_msg+hv_kvp_msg via netlink.
Currently it sets an incorrect iovec size, as reported by valgrind.

In the case of registering with the kernel the allocated buffer is large
enough to hold nlmsghdr+cn_msg+hv_kvp_msg, no overrun happens. In the
case of responding to the kernel the cn_msg is located in the middle of
recv_buffer, after the nlmsghdr. Currently the code in netlink_send adds
also the size of nlmsghdr to the payload. But nlmsghdr is a separate
iovec. This leads to an (harmless) out-of-bounds access when the kernel
processes the iovec. Correct the iovec size of the cn_msg to be just
cn_msg + its payload.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-12 15:44:57 -07:00
Olaf Hering b4919a5f95 Tools: hv: fix send/recv buffer allocation
hv_kvp_daemon fails to start in current openSuSE 13.1 snapshots because
the kvp_send_buffer is too small to hold cn_msg+hv_kvp_msg, the very
first sendmsg returns with EFAULT. In addition it fixes the Network info
tab in Windows Server 2012R2 in SLES11.

Adjust the code in kvp and vss daemon to allocate the needed buffers at
runtime. To keep the code simple, the buffer_len includes also the
nlmsghdr, although only the recv_buffer needs this extra space.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-02 11:44:18 +08:00
Tomas Hozza d12e146924 tools: hv: Check return value of setsockopt call
Check return value of setsockopt call and if it fails print error to the
system log and exit with non-zero value.

Signed-off-by: Tomas Hozza <thozza@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-26 16:40:41 -07:00
Tomas Hozza 9561d47931 tools: hv: Check return value of poll call
Check return value of poll call and if it fails print error to the
system log. If errno is EINVAL then exit with non-zero value otherwise
continue the while loop and call poll again.

Signed-off-by: Tomas Hozza <thozza@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-26 16:40:41 -07:00
Tomas Hozza 5c28926981 tools: hv: Improve error logging in VSS daemon.
Use errno and strerror() when logging errors to provide more
information.

Signed-off-by: Tomas Hozza <thozza@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-26 16:40:41 -07:00
K. Y. Srinivasan 0e27263926 Tools: hv: Fix a checkpatch warning
Fix a checkpatch warning.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-24 09:02:36 -07:00
Olaf Hering 10b637b4c8 tools: hv: skip iso9660 mounts in hv_vss_daemon
fsreeze does not work for iso9660 filesystems. A ENOSUPP may be caught
in the freeze case, but the subsequent thaw call would fail and leads to
a false error.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-24 09:02:35 -07:00
Olaf Hering 7b413b6553 tools: hv: use FIFREEZE/FITHAW in hv_vss_daemon
As suggested by Paolo Bonzini, use ioctl instead of calling fsfreeze.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-24 09:02:35 -07:00
Olaf Hering d3d1ee3ab2 tools: hv: use getmntent in hv_vss_daemon
As suggested by Paolo Bonzini, use getmntent instead of parsing output
of mount(1).

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-24 09:02:35 -07:00
K. Y. Srinivasan 038336a5b4 Tools: hv: Fix a checkpatch warning
Fix a checkpatch warning.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-24 09:02:35 -07:00
Olaf Hering 5edf5ee42a tools: hv: fix checks for origin of netlink message in hv_vss_daemon
Similar to what commit 95a69adab9 ("tools:
hv: Netlink source address validation allows DoS") does in
hv_kvp_daemon, improve checks for origin of netlink connector message.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-24 09:02:35 -07:00
Olaf Hering eb8905b8ff Tools: hv: fix warnings in hv_vss_daemon
This change fixes a few compile errors:

hv_vss_daemon.c:64:15: warning: unknown escape sequence '\/'
hv_vss_daemon.c:64:15: warning: unknown escape sequence '\/'
hv_vss_daemon.c: In function 'vss_operate':
hv_vss_daemon.c:66: warning: 'return' with no value, in function returning non-void
hv_vss_daemon.c: In function 'main':
hv_vss_daemon.c:130: warning: ignoring return value of 'daemon', declared with attribute warn_unused_result
hv_vss_daemon.c: In function 'vss_operate':
hv_vss_daemon.c:47: warning: 'fs_op' may be used uninitialized in this function

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-24 09:02:35 -07:00
K. Y. Srinivasan 96dd86fa58 Drivers: hv: Add a new driver to support host initiated backup
This driver supports host initiated backup of the guest. On Windows guests,
the host can generate application consistent backups using the Windows VSS
framework. On Linux, we ensure that the backup will be file system consistent.
This driver allows the host to initiate a  "Freeze" operation on all the mounted
file systems in the guest. Once the mounted file systems in the guest are frozen,
the host snapshots the guest's file systems. Once this is done, the guest's file
systems are "thawed".

This driver has a user-level component (daemon) that invokes the appropriate
operation on all the mounted file systems in response to the requests from
the host. The duration for which the guest is frozen is very short - a few seconds.
During this interval, the diff disk is comitted.

In this version of the patch I have addressed the feedback from Olaf Herring.
Also, some of the connector related issues have been fixed.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-15 12:12:36 -07:00