[PATCH 3/3] gcc-plugins/stackleak: Ignore .noinstr.text and .entry.text

[Kees Cook]

The .noinstr.text section functions may not have "current()" sanely
available. Similarly true for .entry.text, though such a check is
currently redundant. Add a check for both. In an x86_64 defconfig build,
the following functions no longer receive stackleak instrumentation:

	__do_fast_syscall_32()
	do_int80_syscall_32()
	do_machine_check()
	do_syscall_64()
	exc_general_protection()
	fixup_bad_iret()

Suggested-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Alexander Popov <alex.popov@xxxxxxxxx>
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
 scripts/gcc-plugins/stackleak_plugin.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/scripts/gcc-plugins/stackleak_plugin.c b/scripts/gcc-plugins/stackleak_plugin.c
index 623bcad6d0c7..c8dc7fe4f959 100644
--- a/scripts/gcc-plugins/stackleak_plugin.c
+++ b/scripts/gcc-plugins/stackleak_plugin.c
@@ -463,6 +463,10 @@ static bool stackleak_gate(void)
 			return false;
 		if (STRING_EQUAL(section, ".meminit.text"))
 			return false;
+		if (STRING_EQUAL(section, ".noinstr.text"))
+			return false;
+		if (STRING_EQUAL(section, ".entry.text"))
+			return false;
 	}
 
 	return track_frame_size >= 0;
-- 
2.30.2