[PATCH v2 09/29] vmlinux.lds.h: Move Program Header restoration into NOTES macro

Kees Cook
2019-10-11T00:05:49Z

In preparation for moving NOTES into RO_DATA, make the Program Header
assignment restoration be part of the NOTES macro itself.

Signed-off-by: Kees Cook <keescook@chromium.org>
---
arch/alpha/kernel/vmlinux.lds.S | 5 +----
arch/ia64/kernel/vmlinux.lds.S | 4 +---
arch/mips/kernel/vmlinux.lds.S | 3 +--
arch/powerpc/kernel/vmlinux.lds.S | 4 +---
arch/s390/kernel/vmlinux.lds.S | 4 +---
arch/x86/kernel/vmlinux.lds.S | 3 +--
include/asm-generic/vmlinux.lds.h | 13 +++++++++++--
7 files changed, 17 insertions(+), 19 deletions(-)

diff --git a/arch/alpha/kernel/vmlinux.lds.S b/arch/alpha/kernel/vmlinux.lds.S
index 363a60ba7c31..cdfdc91ce64c 100644
--- a/arch/alpha/kernel/vmlinux.lds.S
+++ b/arch/alpha/kernel/vmlinux.lds.S
@@ -34,10 +34,7 @@ SECTIONS
swapper_pg_dir = SWAPPER_PGD;
_etext = .; /* End of text section */

- NOTES :text :note
- .dummy : {
- *(.dummy)
- } :text
+ NOTES

RODATA
EXCEPTION_TABLE(16)
diff --git a/arch/ia64/kernel/vmlinux.lds.S b/arch/ia64/kernel/vmlinux.lds.S
index 7cf4958b732d..bfc937ec168c 100644
--- a/arch/ia64/kernel/vmlinux.lds.S
+++ b/arch/ia64/kernel/vmlinux.lds.S
@@ -70,9 +70,7 @@ SECTIONS {
/*
* Read-only data
*/
- NOTES :text :note /* put .notes in text and mark in PT_NOTE */
- code_continues : {
- } :text /* switch back to regular program... */
+ NOTES

EXCEPTION_TABLE(16)

diff --git a/arch/mips/kernel/vmlinux.lds.S b/arch/mips/kernel/vmlinux.lds.S
index 1c95612eb800..6a22f531d815 100644
--- a/arch/mips/kernel/vmlinux.lds.S
+++ b/arch/mips/kernel/vmlinux.lds.S
@@ -81,8 +81,7 @@ SECTIONS
__stop___dbe_table = .;
}

- NOTES NOTES_HEADERS
- .dummy : { *(.dummy) } :text
+ NOTES

_sdata = .; /* Start of data section */
RODATA
diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S
index 7e26e20c8324..4f19d814d592 100644
--- a/arch/powerpc/kernel/vmlinux.lds.S
+++ b/arch/powerpc/kernel/vmlinux.lds.S
@@ -164,9 +164,7 @@ SECTIONS
#endif
EXCEPTION_TABLE(0)

- NOTES :text :note
- /* Restore program header away from PT_NOTE. */
- .dummy : { *(.dummy) } :text
+ NOTES

/*
* Init sections discarded at runtime
diff --git a/arch/s390/kernel/vmlinux.lds.S b/arch/s390/kernel/vmlinux.lds.S
index 646d939346df..f88eedeb915a 100644
--- a/arch/s390/kernel/vmlinux.lds.S
+++ b/arch/s390/kernel/vmlinux.lds.S
@@ -52,9 +52,7 @@ SECTIONS
_etext = .; /* End of text section */
} :text = 0x0700

- NOTES :text :note
-
- .dummy : { *(.dummy) } :text
+ NOTES

RO_DATA_SECTION(PAGE_SIZE)

diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
index 2e18bf5c1aed..8be25b09c2b7 100644
--- a/arch/x86/kernel/vmlinux.lds.S
+++ b/arch/x86/kernel/vmlinux.lds.S
@@ -148,8 +148,7 @@ SECTIONS
_etext = .;
} :text = 0x9090

- NOTES :text :note
- .dummy : { *(.dummy) } :text
+ NOTES

EXCEPTION_TABLE(16)

diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index f5dd45ce73f1..97d4299f14dc 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -56,10 +56,18 @@

/*
* Only some architectures want to have the .notes segment visible in
- * a separate PT_NOTE ELF Program Header.
+ * a separate PT_NOTE ELF Program Header. When this happens, it needs
+ * to be visible in both the kernel text's PT_LOAD and the PT_NOTE
+ * Program Headers. In this case, though, the PT_LOAD needs to be made
+ * the default again so that all the following sections don't also end
+ * up in the PT_NOTE Program Header.
*/
#ifdef EMITS_PT_NOTE
#define NOTES_HEADERS :text :note
+#define NOTES_HEADERS_RESTORE __restore_ph : { *(.__restore_ph) } :text
+#else
+#define NOTES_HEADERS
+#define NOTES_HEADERS_RESTORE
#endif

/* Align . to a 8 byte boundary equals to maximum function alignment. */
@@ -798,7 +806,8 @@
__start_notes = .; \
KEEP(*(.note.*)) \
__stop_notes = .; \
- }
+ } NOTES_HEADERS \
+ NOTES_HEADERS_RESTORE

#define INIT_SETUP(initsetup_align) \
. = ALIGN(initsetup_align); \
--
2.17.1