Changeset c49c1fb for chapter08/gcc.xml

Timestamp:

09/11/2022 10:30:10 PM (20 months ago)

Author:

Thomas Trepl (Moody) <thomas@…>

Branches:

multilib

Children:

c1a6423d

Parents:

530771a (diff), e5e442c (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Automatic merge of trunk into multilib

File:

• chapter08/gcc.xml (modified) (3 diffs)

chapter08/gcc.xml

@@ -125 +125 @@
     </variablelist>
 
-    <note id="pie-ssp-info" xreflabel="note on PIE and SSP">
+    <note>
+      <anchor id="pie-ssp-info" xreflabel="note on PIE and SSP"/>
       <para>
-        PIE (position independent executable) is a technique to produce
-        binary programs that can be loaded anywhere in memory. Together
-        with a feature named ASLR (Address Space Layout Randomization),
-        this allows programs to never have the same memory layout,
-        thus defeating attacks based on reproducible memory patterns.
+        PIE (position-independent executable) is a technique to produce
+        binary programs that can be loaded anywhere in memory.  Without PIE,
+        the security feature named ASLR (Address Space Layout Randomization)
+        can be applied for the shared libraries, but not the exectutable
+        itself.  Enabling PIE allows ASLR for the executables in addition to
+        the shared libraries, and mitigates some attacks based on fixed
+        addresses of sensitive code or data in the executables.
       </para>
       <para>
@@ -137 +140 @@
         that the parameter stack is not corrupted. Stack corruption can
         for example alter the return address of a subroutine,
-        which would allow transferring control to an attacker program instead
-        of the original one.
+        which would allow transferring control to some dangerous code
+        (existing in the program or shared libraries, or injected by the
+        attacker somehow) instead of the original one.
       </para>
     </note>
@@ -148 +152 @@
     <important>
       <para>In this section, the test suite for GCC is considered
-      important, but it takes a long time. First time builders are 
+      important, but it takes a long time. First time builders are
       encouraged to not skip it.  The time to run the tests can be
       reduced significantly by adding -jx to the make command below