From 441110a547f86a2fd0c40bf04b274853622c53cc Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Tue, 29 Oct 2019 14:13:30 -0700 Subject: 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 Signed-off-by: Borislav Petkov Acked-by: Heiko Carstens # s390 Cc: Andy Lutomirski Cc: Arnd Bergmann Cc: Dave Hansen 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 Cc: Michal Simek Cc: Rick Edgecombe Cc: Segher Boessenkool Cc: Will Deacon Cc: x86-ml Cc: Yoshinori Sato Link: https://lkml.kernel.org/r/20191029211351.13243-9-keescook@chromium.org --- include/asm-generic/vmlinux.lds.h | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'include/asm-generic') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index dae64600ccbf..f5dd45ce73f1 100644 --- 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) -- cgit From fbe6a8e618a2d70621cff277e24f6eb338d3d149 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Tue, 29 Oct 2019 14:13:31 -0700 Subject: vmlinux.lds.h: Move Program Header restoration into NOTES macro 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 Signed-off-by: Borislav Petkov Acked-by: Heiko Carstens # s390 Cc: Andy Lutomirski Cc: Arnd Bergmann Cc: Dave Hansen 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 Cc: Michal Simek Cc: Rick Edgecombe Cc: Segher Boessenkool Cc: Will Deacon Cc: x86-ml Cc: Yoshinori Sato Link: https://lkml.kernel.org/r/20191029211351.13243-10-keescook@chromium.org --- include/asm-generic/vmlinux.lds.h | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) (limited to 'include/asm-generic') 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); \ -- cgit From eaf937075c9a42eb8ba51eb3050773d7205d3595 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Tue, 29 Oct 2019 14:13:32 -0700 Subject: vmlinux.lds.h: Move NOTES into RO_DATA The .notes section should be non-executable read-only data. As such, move it to the RO_DATA macro instead of being per-architecture defined. Signed-off-by: Kees Cook Signed-off-by: Borislav Petkov Acked-by: Heiko Carstens # s390 Cc: Andy Lutomirski Cc: Arnd Bergmann Cc: Dave Hansen 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 Cc: Michal Simek Cc: Rick Edgecombe Cc: Segher Boessenkool Cc: Will Deacon Cc: x86-ml Cc: Yoshinori Sato Link: https://lkml.kernel.org/r/20191029211351.13243-11-keescook@chromium.org --- include/asm-generic/vmlinux.lds.h | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'include/asm-generic') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 97d4299f14dc..dc3390ec6b60 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -28,7 +28,6 @@ * _edata = .; * * EXCEPTION_TABLE(...) - * NOTES * * BSS_SECTION(0, 0, 0) * _end = .; @@ -512,10 +511,12 @@ __start___modver = .; \ KEEP(*(__modver)) \ __stop___modver = .; \ - . = ALIGN((align)); \ - __end_rodata = .; \ } \ - . = ALIGN((align)); + \ + NOTES \ + \ + . = ALIGN((align)); \ + __end_rodata = .; /* RODATA & RO_DATA provided for backward compatibility. * All archs are supposed to use RO_DATA() */ -- cgit From c82318254d15e5f83c75f60aedf2bb9eb408308f Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Tue, 29 Oct 2019 14:13:33 -0700 Subject: vmlinux.lds.h: Replace RODATA with RO_DATA There's no reason to keep the RODATA macro: replace the callers with the expected RO_DATA macro. Signed-off-by: Kees Cook Signed-off-by: Borislav Petkov Cc: Andy Lutomirski Cc: Arnd Bergmann Cc: Dave Hansen 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 Cc: Michal Simek Cc: Rick Edgecombe Cc: Segher Boessenkool Cc: Will Deacon Cc: x86-ml Cc: Yoshinori Sato Link: https://lkml.kernel.org/r/20191029211351.13243-12-keescook@chromium.org --- include/asm-generic/vmlinux.lds.h | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'include/asm-generic') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index dc3390ec6b60..a0a989fbe411 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -518,9 +518,7 @@ . = ALIGN((align)); \ __end_rodata = .; -/* RODATA & RO_DATA provided for backward compatibility. - * All archs are supposed to use RO_DATA() */ -#define RODATA RO_DATA_SECTION(4096) +/* All archs are supposed to use RO_DATA() */ #define RO_DATA(align) RO_DATA_SECTION(align) /* -- cgit From 93240b327929ff03c1878ea8badc5c6bd86f053f Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Tue, 29 Oct 2019 14:13:34 -0700 Subject: vmlinux.lds.h: Replace RO_DATA_SECTION with RO_DATA Finish renaming RO_DATA_SECTION to RO_DATA. (Calling this a "section" is a lie, since it's multiple sections and section flags cannot be applied to the macro.) Signed-off-by: Kees Cook Signed-off-by: Borislav Petkov Acked-by: Heiko Carstens # s390 Acked-by: Geert Uytterhoeven # m68k Cc: Andy Lutomirski Cc: Arnd Bergmann Cc: Dave Hansen 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 Cc: Michal Simek Cc: Rick Edgecombe Cc: Segher Boessenkool Cc: Will Deacon Cc: x86-ml Cc: Yoshinori Sato Link: https://lkml.kernel.org/r/20191029211351.13243-13-keescook@chromium.org --- include/asm-generic/vmlinux.lds.h | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) (limited to 'include/asm-generic') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index a0a989fbe411..061e57c609f6 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -23,7 +23,7 @@ * _etext = .; * * _sdata = .; - * RO_DATA_SECTION(PAGE_SIZE) + * RO_DATA(PAGE_SIZE) * RW_DATA_SECTION(...) * _edata = .; * @@ -363,7 +363,7 @@ /* * Read only Data */ -#define RO_DATA_SECTION(align) \ +#define RO_DATA(align) \ . = ALIGN((align)); \ .rodata : AT(ADDR(.rodata) - LOAD_OFFSET) { \ __start_rodata = .; \ @@ -518,9 +518,6 @@ . = ALIGN((align)); \ __end_rodata = .; -/* All archs are supposed to use RO_DATA() */ -#define RO_DATA(align) RO_DATA_SECTION(align) - /* * .text section. Map to function alignment to avoid address changes * during second ld run in second ld pass when generating System.map -- cgit From c9174047b48d700a785b633319dd7d27288b86be Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Tue, 29 Oct 2019 14:13:35 -0700 Subject: vmlinux.lds.h: Replace RW_DATA_SECTION with RW_DATA Rename RW_DATA_SECTION to RW_DATA. (Calling this a "section" is a lie, since it's multiple sections and section flags cannot be applied to the macro.) Signed-off-by: Kees Cook Signed-off-by: Borislav Petkov Acked-by: Heiko Carstens # s390 Acked-by: Geert Uytterhoeven # m68k Cc: Andy Lutomirski Cc: Arnd Bergmann Cc: Dave Hansen 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 Cc: Michal Simek Cc: Rick Edgecombe Cc: Segher Boessenkool Cc: Will Deacon Cc: x86-ml Cc: Yoshinori Sato Link: https://lkml.kernel.org/r/20191029211351.13243-14-keescook@chromium.org --- include/asm-generic/vmlinux.lds.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/asm-generic') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 061e57c609f6..356078e50a5c 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -24,7 +24,7 @@ * * _sdata = .; * RO_DATA(PAGE_SIZE) - * RW_DATA_SECTION(...) + * RW_DATA(...) * _edata = .; * * EXCEPTION_TABLE(...) @@ -975,7 +975,7 @@ * matches the requirement of PAGE_ALIGNED_DATA. * * use 0 as page_align if page_aligned data is not used */ -#define RW_DATA_SECTION(cacheline, pagealigned, inittask) \ +#define RW_DATA(cacheline, pagealigned, inittask) \ . = ALIGN(PAGE_SIZE); \ .data : AT(ADDR(.data) - LOAD_OFFSET) { \ INIT_TASK_DATA(inittask) \ -- cgit From b8c2f776164c8f74ac31c5e370ca3f029be0aa19 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Tue, 29 Oct 2019 14:13:36 -0700 Subject: vmlinux.lds.h: Allow EXCEPTION_TABLE to live in RO_DATA Many architectures have an EXCEPTION_TABLE that needs to be only readable. As such, it should live in RO_DATA. Create a macro to identify this case for the architectures that can move EXCEPTION_TABLE into RO_DATA. Signed-off-by: Kees Cook Signed-off-by: Borislav Petkov Acked-by: Will Deacon Cc: Andy Lutomirski Cc: Arnd Bergmann Cc: Dave Hansen 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: linuxppc-dev@lists.ozlabs.org Cc: linux-s390@vger.kernel.org Cc: Michael Ellerman Cc: Michal Simek Cc: Rick Edgecombe Cc: Segher Boessenkool Cc: x86-ml Cc: Yoshinori Sato Link: https://lkml.kernel.org/r/20191029211351.13243-15-keescook@chromium.org --- include/asm-generic/vmlinux.lds.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'include/asm-generic') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 356078e50a5c..9867d8e41eed 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -69,6 +69,17 @@ #define NOTES_HEADERS_RESTORE #endif +/* + * Some architectures have non-executable read-only exception tables. + * They can be added to the RO_DATA segment by specifying their desired + * alignment. + */ +#ifdef RO_EXCEPTION_TABLE_ALIGN +#define RO_EXCEPTION_TABLE EXCEPTION_TABLE(RO_EXCEPTION_TABLE_ALIGN) +#else +#define RO_EXCEPTION_TABLE +#endif + /* Align . to a 8 byte boundary equals to maximum function alignment. */ #define ALIGN_FUNCTION() . = ALIGN(8) @@ -513,6 +524,7 @@ __stop___modver = .; \ } \ \ + RO_EXCEPTION_TABLE \ NOTES \ \ . = ALIGN((align)); \ -- cgit