[PATCH] lxc: fix lxcContainerMountAllFS() DEREF_BEFORE_CHECK

[Dmitry Frolov <frolov@xxxxxxxxx>]

Reviewing the sources, I found, that
in function lxcContainerMountAllFS() pointers
vmDef->fss[i]->src and vmDef->fss[i]->src->path
are checked for NULL after dereferencing in
VIR_DEBUG() macro.

Fixes: 57487085dc ("lxc: don't try to reference NULL when mounting filesystems")
---
 src/lxc/lxc_container.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/lxc/lxc_container.c b/src/lxc/lxc_container.c
index 21220661f7..58a6695458 100644
--- a/src/lxc/lxc_container.c
+++ b/src/lxc/lxc_container.c
@@ -1467,13 +1467,15 @@ static int lxcContainerMountAllFS(virDomainDef *vmDef,
         if (STREQ(vmDef->fss[i]->dst, "/"))
             continue;
 
+        if (!(vmDef->fss[i]->src && vmDef->fss[i]->src->path))
+            return -1;
+
         VIR_DEBUG("Mounting '%s' -> '%s'", vmDef->fss[i]->src->path, vmDef->fss[i]->dst);
 
         if (lxcContainerResolveSymlinks(vmDef->fss[i], false) < 0)
             return -1;
 
-        if (!(vmDef->fss[i]->src && vmDef->fss[i]->src->path &&
-              STRPREFIX(vmDef->fss[i]->src->path, vmDef->fss[i]->dst)) &&
+        if (!STRPREFIX(vmDef->fss[i]->src->path, vmDef->fss[i]->dst) &&
             lxcContainerUnmountSubtree(vmDef->fss[i]->dst, false) < 0)
             return -1;
 
-- 
2.34.1