vmlinux.lds.h: Provide EMIT_PT_NOTE to indicate export of .notes

In preparation for moving NOTES into RO_DATA, provide a mechanism for
architectures that want to emit a PT_NOTE Program Header to do so.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # s390
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-alpha@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-c6x-dev@linux-c6x.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc: Segher Boessenkool <segher@kernel.crashing.org>
Cc: Will Deacon <will@kernel.org>
Cc: x86-ml <x86@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: https://lkml.kernel.org/r/20191029211351.13243-9-keescook@chromium.org

diff --git a/arch/alpha/kernel/vmlinux.lds.S b/arch/alpha/kernel/vmlinux.lds.S
index 781090cacc96dda81e1807b863668dca4035298c..363a60ba7c31aeba1e35d47609c6a7b6e1b1af17 100644 (file)
--- a/arch/alpha/kernel/vmlinux.lds.S
+++ b/arch/alpha/kernel/vmlinux.lds.S
@@ -1,4 +1,7 @@
 /* SPDX-License-Identifier: GPL-2.0 */
+
+#define EMITS_PT_NOTE
+
 #include <asm-generic/vmlinux.lds.h>
 #include <asm/thread_info.h>
 #include <asm/cache.h>

diff --git a/arch/ia64/kernel/vmlinux.lds.S b/arch/ia64/kernel/vmlinux.lds.S
index 2c4f23c390ad21580e6b92bcbc289bcae54502c8..7cf4958b732d01229cc140f7f659bd4c509754dd 100644 (file)
--- a/arch/ia64/kernel/vmlinux.lds.S
+++ b/arch/ia64/kernel/vmlinux.lds.S
@@ -5,6 +5,8 @@
 #include <asm/pgtable.h>
 #include <asm/thread_info.h>
 
+#define EMITS_PT_NOTE
+
 #include <asm-generic/vmlinux.lds.h>
 
 OUTPUT_FORMAT("elf64-ia64-little")

diff --git a/arch/mips/kernel/vmlinux.lds.S b/arch/mips/kernel/vmlinux.lds.S
index 33ee0d18fb0adc21d952c98fbf77b5ed8c514d6a..1c95612eb8005588bcdf015a512997d0d16a29a0 100644 (file)
--- a/arch/mips/kernel/vmlinux.lds.S
+++ b/arch/mips/kernel/vmlinux.lds.S
@@ -10,6 +10,11 @@
  */
 #define BSS_FIRST_SECTIONS *(.bss..swapper_pg_dir)
 
+/* Cavium Octeon should not have a separate PT_NOTE Program Header. */
+#ifndef CONFIG_CAVIUM_OCTEON_SOC
+#define EMITS_PT_NOTE
+#endif
+
 #include <asm-generic/vmlinux.lds.h>
 
 #undef mips
@@ -76,12 +81,7 @@ SECTIONS
                __stop___dbe_table = .;
        }
 
-#ifdef CONFIG_CAVIUM_OCTEON_SOC
-#define NOTES_HEADER
-#else /* CONFIG_CAVIUM_OCTEON_SOC */
-#define NOTES_HEADER :note
-#endif /* CONFIG_CAVIUM_OCTEON_SOC */
-       NOTES :text NOTES_HEADER
+       NOTES NOTES_HEADERS
        .dummy : { *(.dummy) } :text
 
        _sdata = .;                     /* Start of data section */

diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S
index e184a63aa5b06e94967fd897dce8e34553a7c6e3..7e26e20c83245ad588471bc5a231343b2fdbf8b0 100644 (file)
--- a/arch/powerpc/kernel/vmlinux.lds.S
+++ b/arch/powerpc/kernel/vmlinux.lds.S
@@ -6,6 +6,7 @@
 #endif
 
 #define BSS_FIRST_SECTIONS *(.bss.prominit)
+#define EMITS_PT_NOTE
 
 #include <asm/page.h>
 #include <asm-generic/vmlinux.lds.h>

diff --git a/arch/s390/kernel/vmlinux.lds.S b/arch/s390/kernel/vmlinux.lds.S
index 13294fef473e53e6d2869b9b1b92508d22373008..646d939346dfa887a192c72dfab1d83cfbd3f431 100644 (file)
--- a/arch/s390/kernel/vmlinux.lds.S
+++ b/arch/s390/kernel/vmlinux.lds.S
@@ -15,6 +15,8 @@
 /* Handle ro_after_init data on our own. */
 #define RO_AFTER_INIT_DATA
 
+#define EMITS_PT_NOTE
+
 #include <asm-generic/vmlinux.lds.h>
 #include <asm/vmlinux.lds.h>
 

diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
index 788e78978030f9d690354e7cd0310b16c7546e0d..2e18bf5c1aed0b2ddc8ff63c2acc1fcc1f00c947 100644 (file)
--- a/arch/x86/kernel/vmlinux.lds.S
+++ b/arch/x86/kernel/vmlinux.lds.S
@@ -21,6 +21,8 @@
 #define LOAD_OFFSET __START_KERNEL_map
 #endif
 
+#define EMITS_PT_NOTE
+
 #include <asm-generic/vmlinux.lds.h>
 #include <asm/asm-offsets.h>
 #include <asm/thread_info.h>

diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index dae64600ccbffe9d006164de3243bbe284e638a5..f5dd45ce73f169c2b11d5d70ceef27771361a5c8 100644 (file)
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -54,6 +54,14 @@
 #define LOAD_OFFSET 0
 #endif
 
+/*
+ * Only some architectures want to have the .notes segment visible in
+ * a separate PT_NOTE ELF Program Header.
+ */
+#ifdef EMITS_PT_NOTE
+#define NOTES_HEADERS          :text :note
+#endif
+
 /* Align . to a 8 byte boundary equals to maximum function alignment. */
 #define ALIGN_FUNCTION()  . = ALIGN(8)