gcc-plugins/stackleak: Avoid .head.text section

commit e7d24c0aa8e678f41457d1304e2091cac6fd1a2e upstream.

The .head.text section carries the startup code that runs with the MMU
off or with a translation of memory that deviates from the ordinary one.
So avoid instrumentation with the stackleak plugin, which already avoids
.init.text and .noinstr.text entirely.

Fixes: 48204aba801f1b51 ("x86/sme: Move early SME kernel encryption handling into .head.text")
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202403221630.2692c998-oliver.sang@intel.com
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20240328064256.2358634-2-ardb+git@google.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/scripts/gcc-plugins/stackleak_plugin.c b/scripts/gcc-plugins/stackleak_plugin.c
index 42f0252ee2a4edf3d3e0879ae8920717df84302d..e5c63f806ef209f55d2a13421fb9a23640eb295c 100644 (file)
--- a/scripts/gcc-plugins/stackleak_plugin.c
+++ b/scripts/gcc-plugins/stackleak_plugin.c
@@ -467,6 +467,8 @@ static bool stackleak_gate(void)
                        return false;
                if (STRING_EQUAL(section, ".entry.text"))
                        return false;
+               if (STRING_EQUAL(section, ".head.text"))
+                       return false;
        }
 
        return track_frame_size >= 0;