From: Luis Machado <luis.machado@arm.com>
Date: Fri, 11 Aug 2023 06:54:25 +0000 (+0100)
Subject: [Morello/gdbserver] Fix incorrect vector resize operation
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=e4c78b3b86fd2148c37d1870cf8bd663f49d4fe0;p=thirdparty%2Fbinutils-gdb.git

[Morello/gdbserver] Fix incorrect vector resize operation

This patch fixes an incorrect vector resize operation when reading the auxv.  A
mistake makes the current code copy data over the end of the vector buffer,
leading to memory corruption.

Fix this by having a pointer to the end of the vector buffer before resizing the
took place.
---

diff --git a/gdbserver/linux-low.cc b/gdbserver/linux-low.cc
index 110be634f31..34bba30a8b8 100644
--- a/gdbserver/linux-low.cc
+++ b/gdbserver/linux-low.cc
@@ -5788,14 +5788,17 @@ linux_process_target::get_auxv ()
 	}
       else if (n < block_size)
 	{
-	  /* We're done reading data.  */
+	  /* We're done reading data.  Shrink the vector to fit the right size
+	     of the auxv data.  */
 	  auxv.resize (auxv.size () - (block_size - n));
 	  done = true;
 	}
       else
 	{
+	  /* Enlarge the vector so we can fit another chunk of auxv data.  */
+	  size_t old_size = auxv.size ();
 	  auxv.resize (auxv.size () + block_size);
-	  ptr = auxv.data () + auxv.size ();
+	  ptr = auxv.data () + old_size;
 	}
     }