MDEV-18946 munmap of 1 byte during shutdown is EINVAL

In MDEV-10814, a missing argument caused a later optional argument (bool true) to be treated as a size. The unmap of this memory occurs during shutdown and resizing innodb buffer pool. As a result the memory is lost but still allocated until shutdown is completed.

Author: dr-m

storage/innobase/buf/buf0buf.cc

@@ -1571,8 +1571,7 @@ buf_chunk_init(
 
 DBUG_EXECUTE_IF("ib_buf_chunk_init_fails", return(NULL););
 
-chunk->mem = buf_pool->allocator.allocate_large(mem_size,
-&chunk->mem_pfx, true);
+chunk->mem = buf_pool->allocator.allocate_large_dontdump(mem_size, &chunk->mem_pfx);
 
 if (UNIV_UNLIKELY(chunk->mem == NULL)) {
 
@@ -1865,9 +1864,8 @@ buf_pool_init_instance(
 &block->debug_latch));
 }
 
-buf_pool->allocator.deallocate_large(
-chunk->mem, &chunk->mem_pfx, chunk->mem_size(),
-true);
+buf_pool->allocator.deallocate_large_dodump(
+chunk->mem, &chunk->mem_pfx, chunk->mem_size());
 }
 ut_free(buf_pool->chunks);
 buf_pool_mutex_exit(buf_pool);
@@ -2014,8 +2012,8 @@ buf_pool_free_instance(
 ut_d(rw_lock_free(&block->debug_latch));
 }
 
-buf_pool->allocator.deallocate_large(
-chunk->mem, &chunk->mem_pfx, true);
+buf_pool->allocator.deallocate_large_dodump(
+chunk->mem, &chunk->mem_pfx, chunk->mem_size());
 }
 
 for (ulint i = BUF_FLUSH_LRU; i < BUF_FLUSH_N_TYPES; ++i) {
@@ -2892,8 +2890,8 @@ buf_pool_resize()
 &block->debug_latch));
 }
 
-buf_pool->allocator.deallocate_large(
-chunk->mem, &chunk->mem_pfx, true);
+buf_pool->allocator.deallocate_large_dodump(
+chunk->mem, &chunk->mem_pfx, chunk->mem_size());
 
 sum_freed += chunk->size;
 

storage/innobase/include/ut0new.h

@@ -653,13 +653,18 @@ class ut_allocator {
 return(ptr);
 }
 
+pointer
+allocate_large_dontdump(
+size_type	n_elements,
+ut_new_pfx_t*	pfx)
+{
+return allocate_large(n_elements, pfx, true);
+}
 /** Free a memory allocated by allocate_large() and trace the
 deallocation.
 @param[in,out]	ptr	pointer to memory to free
 @param[in]	pfx	descriptor of the memory, as returned by
-allocate_large().
-@param[in] dodump if true, advise the OS to include this
-memory again if a core dump occurs. */
+allocate_large(). */
 void
 deallocate_large(
 pointer	ptr,
@@ -668,12 +673,8 @@ class ut_allocator {
 pfx
 #endif
 ,
-size_tsize,
-booldodump = false)
+size_tsize)
 {
-if (dodump) {
-ut_dodump(ptr, size);
-}
 #ifdef UNIV_PFS_MEMORY
 if (pfx) {
 deallocate_trace(pfx);
@@ -683,8 +684,27 @@ class ut_allocator {
 os_mem_free_large(ptr, size);
 }
 
+void
+deallocate_large_dodump(
+pointer	ptr,
+const ut_new_pfx_t*
 #ifdef UNIV_PFS_MEMORY
+pfx
+#endif
+,
+size_tsize)
+{
+ut_dodump(ptr, size);
+deallocate_large(ptr,
+#ifdef UNIV_PFS_MEMORY
+pfx,
+#else
+NULL,
+#endif
+size);
+}
 
+#ifdef UNIV_PFS_MEMORY
 /** Get the performance schema key to use for tracing allocations.
 @param[in]	file	file name of the caller or NULL if unknown
 @return performance schema key */