libutils: clearer abort on overflow.
Let's turn a bug into a feature... Since this code is built with intsan,
anyone who caused overflow here will have had an abort, so we know
no-one actually needs the BAD_INDEX return that was presumably the
original author's intent. So let's just mandate that, since it's a lot
harder to ignore an abort than it is to ignore an error return.
Bug: http://b/179044558
Test: treehugger
Change-Id: I08f1018f9da1e09de885699138b7543d55bb2a36
diff --git a/libutils/VectorImpl.cpp b/libutils/VectorImpl.cpp
index c97a19b..d951b8b 100644
--- a/libutils/VectorImpl.cpp
+++ b/libutils/VectorImpl.cpp
@@ -279,14 +279,12 @@
ssize_t VectorImpl::removeItemsAt(size_t index, size_t count)
{
- ALOG_ASSERT((index+count)<=size(),
- "[%p] remove: index=%d, count=%d, size=%d",
- this, (int)index, (int)count, (int)size());
-
- if ((index+count) > size())
- return BAD_VALUE;
- _shrink(index, count);
- return index;
+ size_t end;
+ LOG_ALWAYS_FATAL_IF(__builtin_add_overflow(index, count, &end), "overflow: index=%zu count=%zu",
+ index, count);
+ if (end > size()) return BAD_VALUE;
+ _shrink(index, count);
+ return index;
}
void VectorImpl::finish_vector()