crimson/os/seastore/btree: fix minor corner case issue

xxhdx1985126 · xxhdx1985126 · commit 2d5715c00f01 · 2024-08-14T11:00:00.000+08:00
Signed-off-by: Xuehan Xu &lt;xuxuehan@qianxin.com&gt;
diff --git a/src/crimson/os/seastore/btree/fixed_kv_node.h b/src/crimson/os/seastore/btree/fixed_kv_node.h
@@ -148,7 +148,7 @@ struct FixedKVNode : ChildableCachedExtent {
     ceph_assert(iter != copy_dests_by_trans.end());
     auto &copy_dests = static_cast<copy_dests_t&>(*iter);
     auto it = copy_dests.dests_by_key.lower_bound(key);
-    if ((*it)->range.begin > key) {
+    if (it == copy_dests.dests_by_key.end() || (*it)->range.begin > key) {
       ceph_assert(it != copy_dests.dests_by_key.begin());
       --it;
     }

Original file line number	Diff line number	Diff line change
`@@ -148,7 +148,7 @@ struct FixedKVNode : ChildableCachedExtent {`
`148`	`148`	`ceph_assert(iter != copy_dests_by_trans.end());`
`149`	`149`	`auto &copy_dests = static_cast<copy_dests_t&>(*iter);`
`150`	`150`	`auto it = copy_dests.dests_by_key.lower_bound(key);`
`151`		`- if ((*it)->range.begin > key) {`
	`151`	`+ if (it == copy_dests.dests_by_key.end() \|\| (*it)->range.begin > key) {`
`152`	`152`	`ceph_assert(it != copy_dests.dests_by_key.begin());`
`153`	`153`	`--it;`
`154`	`154`	`}`