From 82f4a136bb675d0e6d81881d12536dbf09ca06d8 Mon Sep 17 00:00:00 2001
From: gaopy3 <gao.panyu@qq.com>
Date: Fri, 1 Nov 2024 06:47:33 +0000
Subject: [PATCH] make the behavior of ob_realloc consistent with standard
 realloc when memory allocation fails

---
 .../src/lib/alloc/ob_tenant_ctx_allocator.cpp | 25 ++++++++++---------
 deps/oblib/src/lib/alloc/object_set.cpp       |  9 ++++---
 deps/oblib/src/lib/charset/ob_ctype_uca.cc    | 10 +++++---
 3 files changed, 25 insertions(+), 19 deletions(-)

diff --git a/deps/oblib/src/lib/alloc/ob_tenant_ctx_allocator.cpp b/deps/oblib/src/lib/alloc/ob_tenant_ctx_allocator.cpp
index b8f783132..99cfe081a 100644
--- a/deps/oblib/src/lib/alloc/ob_tenant_ctx_allocator.cpp
+++ b/deps/oblib/src/lib/alloc/ob_tenant_ctx_allocator.cpp
@@ -478,7 +478,8 @@ void* ObTenantCtxAllocator::common_realloc(const void *ptr, const int64_t size,
     LIB_LOG_RET(ERROR, OB_INVALID_ARGUMENT, "OB_MOD_DO_NOT_USE_ME REALLOC", K(size));
   }
 
-  AObject *obj = NULL;
+  AObject *obj = NULL; // original object
+  AObject *nobj = NULL; // newly allocated object
   bool sample_allowed = false;
   bool is_errsim = false;
   if (NULL != ptr) {
@@ -489,7 +490,7 @@ void* ObTenantCtxAllocator::common_realloc(const void *ptr, const int64_t size,
   const ObErrsimModuleType type = THIS_WORKER.get_module_type();
   if (is_errsim_module(ta.get_tenant_id(), type.type_)) {
     //errsim alloc memory failed.
-    obj = nullptr;
+    nobj = nullptr;
     is_errsim = true;
   }
 #endif
@@ -501,17 +502,13 @@ void* ObTenantCtxAllocator::common_realloc(const void *ptr, const int64_t size,
   if (OB_UNLIKELY(OB_FAIL(ret) || is_errsim)) {
     AllocFailedCtx &afc = g_alloc_failed_ctx();
     afc.reason_ = AllocFailedReason::ERRSIM_INJECTION;
-    if (OB_NOT_NULL(obj)) {
-      allocator.free_object(obj);
-      obj = NULL;
-    }
   } else {
     BASIC_TIME_GUARD(time_guard, "ObMalloc");
     DEFER(ObMallocTimeMonitor::get_instance().record_malloc_time(time_guard, size, inner_attr));
     sample_allowed = ObMallocSampleLimiter::malloc_sample_allowed(size, inner_attr);
     inner_attr.alloc_extra_info_ = sample_allowed;
-    obj = allocator.realloc_object(obj, size, inner_attr);
-    if(OB_ISNULL(obj)) {
+    nobj = allocator.realloc_object(obj, size, inner_attr);
+    if(OB_ISNULL(nobj)) {
       int64_t total_size = 0;
       if (g_alloc_failed_ctx().need_wash_block()) {
         total_size += ta.sync_wash();
@@ -521,14 +518,18 @@ void* ObTenantCtxAllocator::common_realloc(const void *ptr, const int64_t size,
         BASIC_TIME_GUARD_CLICK("WASH_CHUNK_END");
       }
       if (total_size > 0) {
-        obj = allocator.realloc_object(obj, size, inner_attr);
+        nobj = allocator.realloc_object(obj, size, inner_attr);
       }
     }
   }
 
-  if (obj != NULL) {
-    on_alloc(*obj, inner_attr);
-    nptr = obj->data_;
+  if (OB_UNLIKELY(NULL == nobj && NULL != obj)) {
+    SANITY_UNPOISON(obj->data_, obj->alloc_bytes_);
+  }
+
+  if (OB_NOT_NULL(nobj)) {
+    on_alloc(*nobj, inner_attr);
+    nptr = nobj->data_;
   } else if (TC_REACH_TIME_INTERVAL(1 * 1000 * 1000)) {
 #ifdef FATAL_ERROR_HANG
     if (REACH_TIME_INTERVAL(60 * 1000 * 1000)) {
diff --git a/deps/oblib/src/lib/alloc/object_set.cpp b/deps/oblib/src/lib/alloc/object_set.cpp
index be0793a1a..11e46b635 100644
--- a/deps/oblib/src/lib/alloc/object_set.cpp
+++ b/deps/oblib/src/lib/alloc/object_set.cpp
@@ -106,11 +106,12 @@ AObject *ObjectSet::realloc_object(
     abort_unless(obj->is_valid());
     uint64_t copy_size = MIN(obj->alloc_bytes_, size);
     new_obj = alloc_object(size, attr);
-    if (NULL != new_obj && copy_size != 0) {
-      memmove(new_obj->data_, obj->data_, copy_size);
+    if (NULL != new_obj) {
+      if (copy_size != 0) {
+        memmove(new_obj->data_, obj->data_, copy_size);
+      }
+      do_free_object(obj);
     }
-
-    do_free_object(obj);
   }
 
   return new_obj;
diff --git a/deps/oblib/src/lib/charset/ob_ctype_uca.cc b/deps/oblib/src/lib/charset/ob_ctype_uca.cc
index 90c4a9ada..f5e4d64b0 100644
--- a/deps/oblib/src/lib/charset/ob_ctype_uca.cc
+++ b/deps/oblib/src/lib/charset/ob_ctype_uca.cc
@@ -1456,10 +1456,14 @@ static int ob_coll_rule_expand(ob_wc_t *wc, size_t limit, ob_wc_t code) {
 }
 static void ob_coll_rule_reset(ObCollRule *r) { memset(r, 0, sizeof(*r)); }
 static int ob_coll_rules_realloc(ObCollRules *rules, size_t n) {
-  if (rules->nrules < rules->mrules ||
-      (rules->rule = static_cast<ObCollRule *>(rules->loader->mem_realloc(
-           rules->rule, sizeof(ObCollRule) * (rules->mrules = n + 128)))))
+  ObCollRule *new_rule = nullptr;
+  if (rules->nrules < rules->mrules)
     return 0;
+  if ((new_rule = static_cast<ObCollRule *>(rules->loader->mem_realloc(
+          rules->rule, sizeof(ObCollRule) * (rules->mrules = n + 128))))) {
+    rules->rule = new_rule;
+    return 0;
+  }
   return -1;
 }
 static int ob_coll_rules_add(ObCollRules *rules, ObCollRule *rule) {