os: fix potential null pointer access

Fixes: #14204
Signed-off-by: xie xingguo <xie.xingguo@zte.com.cn>

diff --git a/src/os/kstore/KStore.cc b/src/os/kstore/KStore.cc
index 039f06981e951a9569cf4536934577c66de85433..5d05fa15d12bd8ac6f5135dd2e3467a2ce0e1351 100644 (file)
--- a/src/os/kstore/KStore.cc
+++ b/src/os/kstore/KStore.cc
@@ -3127,7 +3127,7 @@ int KStore::_truncate(TransContext *txc,
 
   RWLock::WLocker l(c->lock);
   OnodeRef o = c->get_onode(oid, false);
-  if (!o->exists) {
+  if (!o || !o->exists) {
     r = -ENOENT;
     goto out;
   }