In preparation for warning on orphan sections, enforce other
expected-to-be-zero-sized sections (since discarding them might hide
problems with them suddenly gaining unexpected entries).

Signed-off-by: Kees Cook <keesc...@chromium.org>
---
 arch/x86/kernel/vmlinux.lds.S | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
index 7faffe7414d6..d8792f9c536f 100644
--- a/arch/x86/kernel/vmlinux.lds.S
+++ b/arch/x86/kernel/vmlinux.lds.S
@@ -415,6 +415,15 @@ SECTIONS
 
        DISCARDS
 
+       /*
+        * Sections that should stay zero sized, which is safer to
+        * explicitly check instead of blindly discarding.
+        */
+       .got (NOLOAD) : {
+               *(.got) *(.igot.*)
+       }
+       ASSERT(SIZEOF(.got) == 0, "Unexpected GOT entries detected!")
+
        /*
         * Make sure that the .got.plt is either completely empty or it
         * contains only the lazy dispatch entries.
@@ -427,6 +436,21 @@ SECTIONS
               SIZEOF(.got.plt) == 0xc,
 #endif
               "Unexpected GOT/PLT entries detected!")
+
+       .plt (NOLOAD) : {
+               *(.plt) *(.plt.*) *(.iplt)
+       }
+       ASSERT(SIZEOF(.plt) == 0, "Unexpected run-time procedure linkages 
detected!")
+
+       /* ld.lld does not like .rel* sections being made "NOLOAD". */
+       .rel.dyn : {
+               *(.rel.*) *(.rel_*)
+       }
+       ASSERT(SIZEOF(.rel.dyn) == 0, "Unexpected run-time relocations (.rel) 
detected!")
+       .rela.dyn : {
+               *(.rela.*) *(.rela_*)
+       }
+       ASSERT(SIZEOF(.rela.dyn) == 0, "Unexpected run-time relocations (.rela) 
detected!")
 }
 
 #ifdef CONFIG_X86_32
-- 
2.25.1

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