Fix startup to security-relevant statically linked binaries.

Before the change they crash on startup.  Perform IREL relocations
earlier to prevent this.

diff --git a/ChangeLog b/ChangeLog
index 3d22169..dd68e5b 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2009-11-24  Ulrich Drepper  <drepper@redhat.com>
+
+       * csu/elf-init.c (__libc_csu_irel): New function.  Code to perform
+       irel relocations split out from...
+       (__libc_csu_init): ...here.
+       * csu/libc-start.c [!SHARED]: Call __libc_csu_irel early.
+
 2009-11-23  Andreas Schwab  <schwab@redhat.com>
 
        * sysdeps/unix/sysv/linux/x86_64/bits/stat.h: Use struct timespec

diff --git a/csu/elf-init.c b/csu/elf-init.c
index 1d2df62..1e3d6d6 100644 (file)
--- a/csu/elf-init.c
+++ b/csu/elf-init.c
@@ -72,15 +72,14 @@ extern void _fini (void);
 /* These functions are passed to __libc_start_main by the startup code.
    These get statically linked into each program.  For dynamically linked
    programs, this module will come from libc_nonshared.a and differs from
-   the libc.a module in that it doesn't call the preinit array.  */
+   the libc.a module in that it doesn't call the preinit array and performs
+   explicit IREL{,A} relocations.  */
 
-void
-__libc_csu_init (int argc, char **argv, char **envp)
-{
-  /* For dynamically linked executables the preinit array is executed by
-     the dynamic linker (before initializing any shared object.  */
 
 #ifndef LIBC_NONSHARED
+void
+__libc_csu_irel (void)
+{
 # ifdef USE_MULTIARCH
 #  ifdef ELF_MACHINE_IRELA
   {
@@ -98,7 +97,17 @@ __libc_csu_init (int argc, char **argv, char **envp)
   }
 #  endif
 # endif
+}
+#endif
 
+
+void
+__libc_csu_init (int argc, char **argv, char **envp)
+{
+  /* For dynamically linked executables the preinit array is executed by
+     the dynamic linker (before initializing any shared object.  */
+
+#ifndef LIBC_NONSHARED
   /* For static executables, preinit happens right before init.  */
   {
     const size_t size = __preinit_array_end - __preinit_array_start;

diff --git a/csu/libc-start.c b/csu/libc-start.c
index 80b672f..dc7ca55 100644 (file)
--- a/csu/libc-start.c
+++ b/csu/libc-start.c
@@ -24,6 +24,9 @@
 #include <bp-sym.h>
 
 extern void __libc_init_first (int argc, char **argv, char **envp);
+#ifndef SHARED
+extern void __libc_csu_irel (void);
+#endif
 
 extern int __libc_multiple_libcs;
 
@@ -134,6 +137,9 @@ LIBC_START_MAIN (int (*main) (int, char **, char ** MAIN_AUXVEC_DECL),
     }
 # endif
 
+  /* Performe IREL{,A} relocations.  */
+  __libc_csu_irel ();
+
   /* Initialize the thread library at least a bit since the libgcc
      functions are using thread functions if these are available and
      we need to setup errno.  */