lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Tue, 16 Jun 2020 17:33:12 +0200 From: Greg Kroah-Hartman <gregkh@...uxfoundation.org> To: linux-kernel@...r.kernel.org Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>, stable@...r.kernel.org, Nick Desaulniers <ndesaulniers@...gle.com>, Andrew Morton <akpm@...ux-foundation.org>, Nathan Chancellor <natechancellor@...il.com>, Fangrui Song <maskray@...gle.com>, Jeremy Fitzhardinge <jeremy@...p.org>, Thomas Gleixner <tglx@...utronix.de>, Vincenzo Frascino <vincenzo.frascino@....com>, Linus Torvalds <torvalds@...ux-foundation.org>, Jian Cai <jiancai@...gle.com>, Ilie Halip <ilie.halip@...il.com> Subject: [PATCH 5.4 008/134] elfnote: mark all .note sections SHF_ALLOC From: Nick Desaulniers <ndesaulniers@...gle.com> commit 51da9dfb7f20911ae4e79e9b412a9c2d4c373d4b upstream. ELFNOTE_START allows callers to specify flags for .pushsection assembler directives. All callsites but ELF_NOTE use "a" for SHF_ALLOC. For vdso's that explicitly use ELF_NOTE_START and BUILD_SALT, the same section is specified twice after preprocessing, once with "a" flag, once without. Example: .pushsection .note.Linux, "a", @note ; .pushsection .note.Linux, "", @note ; While GNU as allows this ordering, it warns for the opposite ordering, making these directives position dependent. We'd prefer not to precisely match this behavior in Clang's integrated assembler. Instead, the non __ASSEMBLY__ definition of ELF_NOTE uses __attribute__((section(".note.Linux"))) which is created with SHF_ALLOC, so let's make the __ASSEMBLY__ definition of ELF_NOTE consistent with C and just always use "a" flag. This allows Clang to assemble a working mainline (5.6) kernel via: $ make CC=clang AS=clang Signed-off-by: Nick Desaulniers <ndesaulniers@...gle.com> Signed-off-by: Andrew Morton <akpm@...ux-foundation.org> Reviewed-by: Nathan Chancellor <natechancellor@...il.com> Reviewed-by: Fangrui Song <maskray@...gle.com> Cc: Jeremy Fitzhardinge <jeremy@...p.org> Cc: Thomas Gleixner <tglx@...utronix.de> Cc: Vincenzo Frascino <vincenzo.frascino@....com> Link: https://github.com/ClangBuiltLinux/linux/issues/913 Link: http://lkml.kernel.org/r/20200325231250.99205-1-ndesaulniers@google.com Debugged-by: Ilie Halip <ilie.halip@...il.com> Signed-off-by: Linus Torvalds <torvalds@...ux-foundation.org> Cc: Jian Cai <jiancai@...gle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org> --- include/linux/elfnote.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/include/linux/elfnote.h +++ b/include/linux/elfnote.h @@ -54,7 +54,7 @@ .popsection ; #define ELFNOTE(name, type, desc) \ - ELFNOTE_START(name, type, "") \ + ELFNOTE_START(name, type, "a") \ desc ; \ ELFNOTE_END
Powered by blists - more mailing lists