Bug 218741

Summary:	[PATCH] Memcheck does not detect malloc/new/new[] mismatches in applications with custom allocators
Product:	[Developer tools] valgrind	Reporter:	Steve VanDeBogart <vandebo-valgrind>
Component:	memcheck	Assignee:	Julian Seward <jseward>
Status:	REPORTED ---
Severity:	normal
Priority:	NOR
Version First Reported In:	unspecified
Target Milestone:	---
Platform:	Compiled Sources
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:
Attachments:	Add new-like and new[]-like block client requests.

Description Steve VanDeBogart 2009-12-15 01:33:32 UTC

Version:            (using Devel)
OS:                Linux
Installed from:    Compiled sources

The client request VG_USERREQ__MALLOCLIKE_BLOCK does not allow the caller to specify the allocation type (malloc,new,new[]) and therefore memcheck can not detect mismatches between the allocation and free type.

A prime example of where this is a problem is in bug 217615 (http://bugs.kde.org/show_bug.cgi?id=217615)

One likely reason that this isn't already implemented is that the MC_Chunk structure is short on space to store addition state.

Attached is a patch that adds additional user requests to mark block as new-like and new[]-like.  It steals a bit from ExeContext in order to store the additional state.

Comment 1 Steve VanDeBogart 2009-12-15 01:37:23 UTC

Created attachment 39060 [details]
Add new-like and new[]-like block client requests.

Add new-like and new[]-like block client requests.  (C) Google.