diff mbox series

[5/8] savevm: Fix memory leak of vmstate_configuration

Message ID 20201226103347.868-6-gaojinhao@huawei.com
State New
Headers show
Series Fix memory leak of some device state in migration | expand

Commit Message

gaojinhao Dec. 26, 2020, 10:33 a.m. UTC 
From: Jinhao Gao <gaojinhao@huawei.com>

When VM migrate VMState of configuration, the fields(name and capabilities)
of configuration having a flag of VMS_ALLOC need to allocate memory. If the
src doesn't free memory of capabilities in SaveState after save VMState of
configuration, or the dst doesn't free memory of name and capabilities in post
load of configuration, it may result in memory leak of name and capabilities.
We free memory in configuration_post_save and configuration_post_load func,
which prevents memory leak.

Signed-off-by: Jinhao Gao <gaojinhao@huawei.com>
---
 migration/savevm.c | 31 +++++++++++++++++++++++++++----
 1 file changed, 27 insertions(+), 4 deletions(-)
diff mbox series

Patch

diff --git a/migration/savevm.c b/migration/savevm.c
index 5f937a2762..13f1a5dab7 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -314,6 +314,16 @@  static int configuration_pre_save(void *opaque)
     return 0;
 }
 
+static int configuration_post_save(void *opaque)
+{
+    SaveState *state = opaque;
+
+    g_free(state->capabilities);
+    state->capabilities = NULL;
+    state->caps_count = 0;
+    return 0;
+}
+
 static int configuration_pre_load(void *opaque)
 {
     SaveState *state = opaque;
@@ -364,24 +374,36 @@  static int configuration_post_load(void *opaque, int version_id)
 {
     SaveState *state = opaque;
     const char *current_name = MACHINE_GET_CLASS(current_machine)->name;
+    int ret = 0;
 
     if (strncmp(state->name, current_name, state->len) != 0) {
         error_report("Machine type received is '%.*s' and local is '%s'",
                      (int) state->len, state->name, current_name);
-        return -EINVAL;
+        ret = -EINVAL;
+        goto out;
     }
 
     if (state->target_page_bits != qemu_target_page_bits()) {
         error_report("Received TARGET_PAGE_BITS is %d but local is %d",
                      state->target_page_bits, qemu_target_page_bits());
-        return -EINVAL;
+        ret = -EINVAL;
+        goto out;
     }
 
     if (!configuration_validate_capabilities(state)) {
-        return -EINVAL;
+        ret = -EINVAL;
+        goto out;
     }
 
-    return 0;
+out:
+    g_free((void *)state->name);
+    state->name = NULL;
+    state->len = 0;
+    g_free(state->capabilities);
+    state->capabilities = NULL;
+    state->caps_count = 0;
+
+    return ret;
 }
 
 static int get_capability(QEMUFile *f, void *pv, size_t size,
@@ -515,6 +537,7 @@  static const VMStateDescription vmstate_configuration = {
     .pre_load = configuration_pre_load,
     .post_load = configuration_post_load,
     .pre_save = configuration_pre_save,
+    .post_save = configuration_post_save,
     .fields = (VMStateField[]) {
         VMSTATE_UINT32(len, SaveState),
         VMSTATE_VBUFFER_ALLOC_UINT32(name, SaveState, 0, NULL, len),