2:08 p.m.
Upstream qemu has raised a concern about whether dumping guest
memory by reading guest paging tables is a security hole:
https://lists.gnu.org/archive/html/qemu-devel/2012-09/msg02607.html
While auditing libvirt to see if we would be impacted, I noticed
that we had some dead code. It is simpler to nuke the dead code
and limit our monitor code to just the subset we make use of.
* src/qemu/qemu_monitor.h (QEMU_MONITOR_DUMP): Drop poorly named
and mostly-unused enum.
* src/qemu/qemu_monitor.c (qemuMonitorDumpToFd): Drop arguments.
* src/qemu/qemu_monitor_json.h (qemuMonitorJSONDump): Likewise.
* src/qemu/qemu_monitor_json.c (qemuMonitorJSONDump): Likewise.
* src/qemu/qemu_driver.c (qemuDumpToFd): Update caller.
---
src/qemu/qemu_driver.c | 2 +-
src/qemu/qemu_monitor.c | 12 ++++--------
src/qemu/qemu_monitor.h | 11 +----------
src/qemu/qemu_monitor_json.c | 24 +++++++-----------------
src/qemu/qemu_monitor_json.h | 5 +----
5 files changed, 14 insertions(+), 40 deletions(-)
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index f14c220..e6e5d02 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -3136,7 +3136,7 @@ static int qemuDumpToFd(struct qemud_driver *driver, virDomainObjPtr
vm,
if (qemuDomainObjEnterMonitorAsync(driver, vm, asyncJob) < 0)
return -1;
- ret = qemuMonitorDumpToFd(priv->mon, 0, fd, 0, 0);
+ ret = qemuMonitorDumpToFd(priv->mon, fd);
qemuDomainObjExitMonitorWithDriver(driver, vm);
return ret;
diff --git a/src/qemu/qemu_monitor.c b/src/qemu/qemu_monitor.c
index b7730fd..b772b28 100644
--- a/src/qemu/qemu_monitor.c
+++ b/src/qemu/qemu_monitor.c
@@ -2045,15 +2045,11 @@ int qemuMonitorMigrateCancel(qemuMonitorPtr mon)
return ret;
}
-int qemuMonitorDumpToFd(qemuMonitorPtr mon,
- unsigned int flags,
- int fd,
- unsigned long long begin,
- unsigned long long length)
+int
+qemuMonitorDumpToFd(qemuMonitorPtr mon, int fd)
{
int ret;
- VIR_DEBUG("mon=%p fd=%d flags=%x begin=%llx length=%llx",
- mon, fd, flags, begin, length);
+ VIR_DEBUG("mon=%p fd=%d", mon, fd);
if (!mon) {
virReportError(VIR_ERR_INVALID_ARG, "%s",
@@ -2073,7 +2069,7 @@ int qemuMonitorDumpToFd(qemuMonitorPtr mon,
if (qemuMonitorSendFileHandle(mon, "dump", fd) < 0)
return -1;
- ret = qemuMonitorJSONDump(mon, flags, "fd:dump", begin, length);
+ ret = qemuMonitorJSONDump(mon, "fd:dump");
if (ret < 0) {
if (qemuMonitorCloseFileHandle(mon, "dump") < 0)
diff --git a/src/qemu/qemu_monitor.h b/src/qemu/qemu_monitor.h
index e37dac8..232ae96 100644
--- a/src/qemu/qemu_monitor.h
+++ b/src/qemu/qemu_monitor.h
@@ -387,17 +387,8 @@ int qemuMonitorMigrateToUnix(qemuMonitorPtr mon,
int qemuMonitorMigrateCancel(qemuMonitorPtr mon);
-typedef enum {
- QEMU_MONITOR_DUMP_HAVE_FILTER = 1 << 0,
- QEMU_MONITOR_DUMP_PAGING = 1 << 1,
- QEMU_MONITOR_DUMP_FLAGS_LAST
-} QEMU_MONITOR_DUMP;
-
int qemuMonitorDumpToFd(qemuMonitorPtr mon,
- unsigned int flags,
- int fd,
- unsigned long long begin,
- unsigned long long length);
+ int fd);
int qemuMonitorGraphicsRelocate(qemuMonitorPtr mon,
int type,
diff --git a/src/qemu/qemu_monitor_json.c b/src/qemu/qemu_monitor_json.c
index b23be1e..a5198b0 100644
--- a/src/qemu/qemu_monitor_json.c
+++ b/src/qemu/qemu_monitor_json.c
@@ -2552,28 +2552,18 @@ int qemuMonitorJSONMigrateCancel(qemuMonitorPtr mon)
return ret;
}
-int qemuMonitorJSONDump(qemuMonitorPtr mon,
- unsigned int flags,
- const char *protocol,
- unsigned long long begin,
- unsigned long long length)
+int
+qemuMonitorJSONDump(qemuMonitorPtr mon,
+ const char *protocol)
{
int ret;
virJSONValuePtr cmd = NULL;
virJSONValuePtr reply = NULL;
- if (flags & QEMU_MONITOR_DUMP_HAVE_FILTER)
- cmd = qemuMonitorJSONMakeCommand("dump-guest-memory",
- "b:paging", flags &
QEMU_MONITOR_DUMP_PAGING ? 1 : 0,
- "s:protocol", protocol,
- "U:begin", begin,
- "U:length", length,
- NULL);
- else
- cmd = qemuMonitorJSONMakeCommand("dump-guest-memory",
- "b:paging", flags &
QEMU_MONITOR_DUMP_PAGING ? 1 : 0,
- "s:protocol", protocol,
- NULL);
+ cmd = qemuMonitorJSONMakeCommand("dump-guest-memory",
+ "b:paging", false,
+ "s:protocol", protocol,
+ NULL);
if (!cmd)
return -1;
diff --git a/src/qemu/qemu_monitor_json.h b/src/qemu/qemu_monitor_json.h
index bdcf819..b592d12 100644
--- a/src/qemu/qemu_monitor_json.h
+++ b/src/qemu/qemu_monitor_json.h
@@ -138,10 +138,7 @@ int qemuMonitorJSONMigrate(qemuMonitorPtr mon,
int qemuMonitorJSONMigrateCancel(qemuMonitorPtr mon);
int qemuMonitorJSONDump(qemuMonitorPtr mon,
- unsigned int flags,
- const char *protocol,
- unsigned long long begin,
- unsigned long long length);
+ const char *protocol);
int qemuMonitorJSONGraphicsRelocate(qemuMonitorPtr mon,
int type,
--
1.7.11.4