From: Nicholas Piggin <npiggin@gmail.com>
To: Andrew Morton <akpm@linux-foundation.org>,
Arnd Bergmann <arnd@arndb.de>,
Benjamin Herrenschmidt <benh@kernel.crashing.org>,
Christophe Leroy <christophe.leroy@csgroup.eu>,
Helge Deller <deller@gmx.de>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
"James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>,
Kees Cook <keescook@chromium.org>,
Michael Ellerman <mpe@ellerman.id.au>,
Paul Mackerras <paulus@samba.org>
Cc: linux-arch@vger.kernel.org, linux-ia64@vger.kernel.org,
linux-parisc@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org
Subject: Re: [PATCH v2 06/13] asm-generic: Use HAVE_FUNCTION_DESCRIPTORS to define associated stubs
Date: Fri, 15 Oct 2021 16:16:12 +1000 [thread overview]
Message-ID: <1634278340.5yp7xtm7um.astroid@bobo.none> (raw)
In-Reply-To: <4fda65cda906e56aa87806b658e0828c64792403.1634190022.git.christophe.leroy@csgroup.eu>
Excerpts from Christophe Leroy's message of October 14, 2021 3:49 pm:
> Replace HAVE_DEREFERENCE_FUNCTION_DESCRIPTOR by
> HAVE_FUNCTION_DESCRIPTORS and use it instead of
> 'dereference_function_descriptor' macro to know
> whether an arch has function descriptors.
>
> To limit churn in one of the following patches, use
> an #ifdef/#else construct with empty first part
> instead of an #ifndef in asm-generic/sections.h
Is it worth putting this into Kconfig if you're going to
change it? In any case
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
>
> Reviewed-by: Kees Cook <keescook@chromium.org>
> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
> ---
> arch/ia64/include/asm/sections.h | 5 +++--
> arch/parisc/include/asm/sections.h | 6 ++++--
> arch/powerpc/include/asm/sections.h | 6 ++++--
> include/asm-generic/sections.h | 3 ++-
> include/linux/kallsyms.h | 2 +-
> 5 files changed, 14 insertions(+), 8 deletions(-)
>
> diff --git a/arch/ia64/include/asm/sections.h b/arch/ia64/include/asm/sections.h
> index 35f24e52149a..6e55e545bf02 100644
> --- a/arch/ia64/include/asm/sections.h
> +++ b/arch/ia64/include/asm/sections.h
> @@ -9,6 +9,9 @@
>
> #include <linux/elf.h>
> #include <linux/uaccess.h>
> +
> +#define HAVE_FUNCTION_DESCRIPTORS 1
> +
> #include <asm-generic/sections.h>
>
> extern char __phys_per_cpu_start[];
> @@ -27,8 +30,6 @@ extern char __start_gate_brl_fsys_bubble_down_patchlist[], __end_gate_brl_fsys_b
> extern char __start_unwind[], __end_unwind[];
> extern char __start_ivt_text[], __end_ivt_text[];
>
> -#define HAVE_DEREFERENCE_FUNCTION_DESCRIPTOR 1
> -
> #undef dereference_function_descriptor
> static inline void *dereference_function_descriptor(void *ptr)
> {
> diff --git a/arch/parisc/include/asm/sections.h b/arch/parisc/include/asm/sections.h
> index bb52aea0cb21..85149a89ff3e 100644
> --- a/arch/parisc/include/asm/sections.h
> +++ b/arch/parisc/include/asm/sections.h
> @@ -2,6 +2,10 @@
> #ifndef _PARISC_SECTIONS_H
> #define _PARISC_SECTIONS_H
>
> +#ifdef CONFIG_64BIT
> +#define HAVE_FUNCTION_DESCRIPTORS 1
> +#endif
> +
> /* nothing to see, move along */
> #include <asm-generic/sections.h>
>
> @@ -9,8 +13,6 @@ extern char __alt_instructions[], __alt_instructions_end[];
>
> #ifdef CONFIG_64BIT
>
> -#define HAVE_DEREFERENCE_FUNCTION_DESCRIPTOR 1
> -
> #undef dereference_function_descriptor
> void *dereference_function_descriptor(void *);
>
> diff --git a/arch/powerpc/include/asm/sections.h b/arch/powerpc/include/asm/sections.h
> index 32e7035863ac..bba97b8c38cf 100644
> --- a/arch/powerpc/include/asm/sections.h
> +++ b/arch/powerpc/include/asm/sections.h
> @@ -8,6 +8,10 @@
>
> #define arch_is_kernel_initmem_freed arch_is_kernel_initmem_freed
>
> +#ifdef PPC64_ELF_ABI_v1
> +#define HAVE_FUNCTION_DESCRIPTORS 1
> +#endif
> +
> #include <asm-generic/sections.h>
>
> extern bool init_mem_is_free;
> @@ -69,8 +73,6 @@ static inline int overlaps_kernel_text(unsigned long start, unsigned long end)
>
> #ifdef PPC64_ELF_ABI_v1
>
> -#define HAVE_DEREFERENCE_FUNCTION_DESCRIPTOR 1
> -
> #undef dereference_function_descriptor
> static inline void *dereference_function_descriptor(void *ptr)
> {
> diff --git a/include/asm-generic/sections.h b/include/asm-generic/sections.h
> index d16302d3eb59..b677e926e6b3 100644
> --- a/include/asm-generic/sections.h
> +++ b/include/asm-generic/sections.h
> @@ -59,7 +59,8 @@ extern char __noinstr_text_start[], __noinstr_text_end[];
> extern __visible const void __nosave_begin, __nosave_end;
>
> /* Function descriptor handling (if any). Override in asm/sections.h */
> -#ifndef dereference_function_descriptor
> +#ifdef HAVE_FUNCTION_DESCRIPTORS
> +#else
> #define dereference_function_descriptor(p) ((void *)(p))
> #define dereference_kernel_function_descriptor(p) ((void *)(p))
> #endif
> diff --git a/include/linux/kallsyms.h b/include/linux/kallsyms.h
> index a1d6fc82d7f0..9f277baeb559 100644
> --- a/include/linux/kallsyms.h
> +++ b/include/linux/kallsyms.h
> @@ -57,7 +57,7 @@ static inline int is_ksym_addr(unsigned long addr)
>
> static inline void *dereference_symbol_descriptor(void *ptr)
> {
> -#ifdef HAVE_DEREFERENCE_FUNCTION_DESCRIPTOR
> +#ifdef HAVE_FUNCTION_DESCRIPTORS
> struct module *mod;
>
> ptr = dereference_kernel_function_descriptor(ptr);
> --
> 2.31.1
>
>
>
next prev parent reply other threads:[~2021-10-15 6:17 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-10-14 5:49 [PATCH v2 00/13] Fix LKDTM for PPC64/IA64/PARISC Christophe Leroy
2021-10-14 5:49 ` [PATCH v2 01/13] powerpc: Move 'struct ppc64_opd_entry' back into asm/elf.h Christophe Leroy
2021-10-14 21:26 ` Daniel Axtens
2021-10-15 5:57 ` Nicholas Piggin
2021-10-14 5:49 ` [PATCH v2 02/13] powerpc: Rename 'funcaddr' to 'addr' in 'struct ppc64_opd_entry' Christophe Leroy
2021-10-14 21:45 ` Daniel Axtens
2021-10-15 4:59 ` Christophe Leroy
2021-10-15 6:01 ` Nicholas Piggin
2021-10-14 5:49 ` [PATCH v2 03/13] powerpc: Remove func_descr_t Christophe Leroy
2021-10-14 22:17 ` Daniel Axtens
2021-10-15 5:19 ` Christophe Leroy
2021-10-15 6:11 ` Nicholas Piggin
2021-10-14 5:49 ` [PATCH v2 04/13] powerpc: Prepare func_desc_t for refactorisation Christophe Leroy
2021-10-14 5:49 ` [PATCH v2 05/13] ia64: Rename 'ip' to 'addr' in 'struct fdesc' Christophe Leroy
2021-10-14 5:49 ` [PATCH v2 06/13] asm-generic: Use HAVE_FUNCTION_DESCRIPTORS to define associated stubs Christophe Leroy
2021-10-15 6:16 ` Nicholas Piggin [this message]
2021-10-15 6:24 ` Christophe Leroy
2021-10-15 8:02 ` Nicholas Piggin
2021-10-15 11:52 ` Nicholas Piggin
2021-10-14 5:49 ` [PATCH v2 07/13] asm-generic: Define 'func_desc_t' to commonly describe function descriptors Christophe Leroy
2021-10-14 6:52 ` Arnd Bergmann
2021-10-14 5:49 ` [PATCH v2 08/13] asm-generic: Refactor dereference_[kernel]_function_descriptor() Christophe Leroy
2021-10-15 7:00 ` Nicholas Piggin
2021-10-14 5:49 ` [PATCH v2 09/13] lkdtm: Force do_nothing() out of line Christophe Leroy
2021-10-14 5:49 ` [PATCH v2 10/13] lkdtm: Really write into kernel text in WRITE_KERN Christophe Leroy
2021-10-14 5:50 ` [PATCH v2 11/13] lkdtm: Fix lkdtm_EXEC_RODATA() Christophe Leroy
2021-10-15 21:32 ` Kees Cook
2021-10-16 6:41 ` Christophe Leroy
2021-10-17 7:50 ` Christophe Leroy
2021-10-14 5:50 ` [PATCH v2 12/13] lkdtm: Fix execute_[user]_location() Christophe Leroy
2021-10-15 21:31 ` Kees Cook
2021-10-16 6:42 ` Christophe Leroy
2021-11-16 15:07 ` Christophe Leroy
2021-10-14 5:50 ` [PATCH v2 13/13] lkdtm: Add a test for function descriptors protection Christophe Leroy
2021-10-15 21:35 ` Kees Cook
2021-10-16 6:28 ` Christophe Leroy
2021-10-14 21:35 ` [PATCH v2 00/13] Fix LKDTM for PPC64/IA64/PARISC Daniel Axtens
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1634278340.5yp7xtm7um.astroid@bobo.none \
--to=npiggin@gmail.com \
--cc=James.Bottomley@HansenPartnership.com \
--cc=akpm@linux-foundation.org \
--cc=arnd@arndb.de \
--cc=benh@kernel.crashing.org \
--cc=christophe.leroy@csgroup.eu \
--cc=deller@gmx.de \
--cc=gregkh@linuxfoundation.org \
--cc=keescook@chromium.org \
--cc=linux-arch@vger.kernel.org \
--cc=linux-ia64@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linux-parisc@vger.kernel.org \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=mpe@ellerman.id.au \
--cc=paulus@samba.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).