From 07bdd852d2eae2de46f5d6038d3db46d87503f00 Mon Sep 17 00:00:00 2001 From: Amos Jeffries Date: Fri, 7 Mar 2014 04:18:03 -0700 Subject: [PATCH] Protect MemBlob::append() against raw-space writes There is no guarantee that the 'unused' area of MemBlob is actually unused. For example if a read buffer was being filled into the rawSpace() of a SBuf or MemBlob it will overlap with this empty area until a read call updates the related size state in MemBlob/SBuf. For these cases we must use memmove() which guarantees no buffer corruption will take place on memory overlaps. --- src/MemBlob.cc | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/src/MemBlob.cc b/src/MemBlob.cc index 7662c11a4e..d3ee617bc6 100644 --- a/src/MemBlob.cc +++ b/src/MemBlob.cc @@ -139,8 +139,7 @@ MemBlob::append(const char *source, const size_type n) if (n > 0) { // appending zero bytes is allowed but only affects the stats Must(willFit(n)); Must(source); - /// \note memcpy() is safe because we copy to an unused area - memcpy(mem + size, source, n); + memmove(mem + size, source, n); size += n; } ++Stats.append; -- 2.47.2