<html>
<head>
<base href="https://bugs.llvm.org/">
</head>
<body><table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Off-by-one in array-bounds sanitizer"
href="https://bugs.llvm.org/show_bug.cgi?id=45938">45938</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>Off-by-one in array-bounds sanitizer
</td>
</tr>
<tr>
<th>Product</th>
<td>clang
</td>
</tr>
<tr>
<th>Version</th>
<td>10.0
</td>
</tr>
<tr>
<th>Hardware</th>
<td>PC
</td>
</tr>
<tr>
<th>OS</th>
<td>Linux
</td>
</tr>
<tr>
<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Severity</th>
<td>normal
</td>
</tr>
<tr>
<th>Priority</th>
<td>P
</td>
</tr>
<tr>
<th>Component</th>
<td>LLVM Codegen
</td>
</tr>
<tr>
<th>Assignee</th>
<td>unassignedclangbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>hahn@absint.com
</td>
</tr>
<tr>
<th>CC</th>
<td>llvm-bugs@lists.llvm.org, neeilans@live.com, richard-llvm@metafoo.co.uk
</td>
</tr></table>
<p>
<div>
<pre>Created <span class=""><a href="attachment.cgi?id=23490" name="attach_23490" title="Testcase">attachment 23490</a> <a href="attachment.cgi?id=23490&action=edit" title="Testcase">[details]</a></span>
Testcase
If the expression a[i] is used in a pre/post inc/dec operation, the sanitizer
of array-bounds treats the expression as &a[i], i.e. it checks for <= bound
instead of < bound, although a[i] is read and written.
I think, the problem can be fixed by replacing EmitLValue by EmitCheckedLValue
in VisitUnaryPostDec and others in clang/lib/CodeGen/CGExprScalar.cpp.</pre>
</div>
</p>
<hr>
<span>You are receiving this mail because:</span>
<ul>
<li>You are on the CC list for the bug.</li>
</ul>
</body>
</html>