[PATCH] Support AT_FXRNG and AT_KPRELOAD on FreeBSD.

[John Baldwin]

FreeBSD's kernel has recently added two new ELF auxiliary vector
entries.  AT_FXRNG points to a root seed version for the kernel's
PRNG.  Userland can use this to reseed a userland PRNG after the
kernel's PRNG has reseeded.  AT_KPRELOAD is the base address of a
kernel-provided vDSO.

This change displays the proper name and description of these entries
in 'info auxv'.

include/ChangeLog:

	* elf/common.h (AT_FREEBSD_FXRNG, AT_FREEBSD_KPRELOAD): Define.
---
 gdb/fbsd-tdep.c      | 2 ++
 include/ChangeLog    | 4 ++++
 include/elf/common.h | 2 ++
 3 files changed, 8 insertions(+)

diff --git a/gdb/fbsd-tdep.c b/gdb/fbsd-tdep.c
index 4da7798544b..346ff7b602b 100644
--- a/gdb/fbsd-tdep.c
+++ b/gdb/fbsd-tdep.c
@@ -1565,6 +1565,8 @@ fbsd_print_auxv_entry (struct gdbarch *gdbarch, struct ui_file *file,
       TAG (ENVC, _("Environment count"), AUXV_FORMAT_DEC);
       TAG (ENVV, _("Environment vector"), AUXV_FORMAT_HEX);
       TAG (PS_STRINGS, _("Pointer to ps_strings"), AUXV_FORMAT_HEX);
+      TAG (FXRNG, _("Pointer to root RNG seed version"), AUXV_FORMAT_HEX);
+      TAG (KPRELOAD, _("Base address of vDSO"), AUXV_FORMAT_HEX);
     }
 
   fprint_auxv_entry (file, name, description, format, type, val);
diff --git a/include/ChangeLog b/include/ChangeLog
index c5b3631ae83..27ddd636c08 100644
--- a/include/ChangeLog
+++ b/include/ChangeLog
@@ -1,3 +1,7 @@
+2021-12-06  John Baldwin  <jhb@FreeBSD.org>
+
+	* elf/common.h (AT_FREEBSD_FXRNG, AT_FREEBSD_KPRELOAD): Define.
+
 2021-12-01  Nick Clifton  <nickc@redhat.com>
 
 	PR 28630
diff --git a/include/elf/common.h b/include/elf/common.h
index 61cfaacfe6c..66bc06ff326 100644
--- a/include/elf/common.h
+++ b/include/elf/common.h
@@ -1392,6 +1392,8 @@
 #define AT_FREEBSD_ENVC         30      /* Environment count. */
 #define AT_FREEBSD_ENVV         31      /* Environment vvector. */
 #define AT_FREEBSD_PS_STRINGS   32      /* struct ps_strings. */
+#define AT_FREEBSD_FXRNG        33      /* Pointer to root RNG seed version. */
+#define AT_FREEBSD_KPRELOAD     34      /* Base of vdso. */
 
 #define AT_SUN_UID      2000    /* Effective user ID.  */
 #define AT_SUN_RUID     2001    /* Real user ID.  */
-- 
2.32.0