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 PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Tue, 3 May 2022 09:57:09 +0900 From: Masahiro Yamada <masahiroy@...nel.org> To: Alexander Lobakin <alexandr.lobakin@...el.com> Cc: linux-hardening@...r.kernel.org, X86 ML <x86@...nel.org>, Borislav Petkov <bp@...en8.de>, Jesse Brandeburg <jesse.brandeburg@...el.com>, Kristen Carlson Accardi <kristen@...ux.intel.com>, Kees Cook <keescook@...omium.org>, Miklos Szeredi <miklos@...redi.hu>, Ard Biesheuvel <ardb@...nel.org>, Tony Luck <tony.luck@...el.com>, Bruce Schlobohm <bruce.schlobohm@...el.com>, Jessica Yu <jeyu@...nel.org>, kernel test robot <lkp@...el.com>, Miroslav Benes <mbenes@...e.cz>, Evgenii Shatokhin <eshatokhin@...tuozzo.com>, Jonathan Corbet <corbet@....net>, Michal Marek <michal.lkml@...kovi.net>, Nick Desaulniers <ndesaulniers@...gle.com>, Herbert Xu <herbert@...dor.apana.org.au>, "David S. Miller" <davem@...emloft.net>, Thomas Gleixner <tglx@...utronix.de>, Will Deacon <will@...nel.org>, Ingo Molnar <mingo@...hat.com>, Christoph Hellwig <hch@....de>, Dave Hansen <dave.hansen@...ux.intel.com>, "H. Peter Anvin" <hpa@...or.com>, Andy Lutomirski <luto@...nel.org>, Peter Zijlstra <peterz@...radead.org>, Arnd Bergmann <arnd@...db.de>, Josh Poimboeuf <jpoimboe@...hat.com>, Nathan Chancellor <nathan@...nel.org>, Masami Hiramatsu <mhiramat@...nel.org>, Marios Pomonis <pomonis@...gle.com>, Sami Tolvanen <samitolvanen@...gle.com>, "H.J. Lu" <hjl.tools@...il.com>, Nicolas Pitre <nico@...xnic.net>, Linux Kernel Mailing List <linux-kernel@...r.kernel.org>, Linux Kbuild mailing list <linux-kbuild@...r.kernel.org>, linux-arch <linux-arch@...r.kernel.org>, live-patching@...r.kernel.org, clang-built-linux <llvm@...ts.linux.dev> Subject: Re: [PATCH v10 01/15] modpost: fix removing numeric suffixes On Thu, Feb 10, 2022 at 3:59 AM Alexander Lobakin <alexandr.lobakin@...el.com> wrote: > > `-z unique-symbol` linker flag which is planned to use with FG-KASLR > to simplify livepatching (hopefully globally later on) triggers the > following: > > ERROR: modpost: "param_set_uint.0" [vmlinux] is a static EXPORT_SYMBOL > > The reason is that for now the condition from remove_dot(): > > if (m && (s[n + m] == '.' || s[n + m] == 0)) > > which was designed to test if it's a dot or a '\0' after the suffix > is never satisfied. > This is due to that `s[n + m]` always points to the last digit of a > numeric suffix, not on the symbol next to it (from a custom debug > print added to modpost): > > param_set_uint.0, s[n + m] is '0', s[n + m + 1] is '\0' > > So it's off-by-one and was like that since 2014. > Fix this for the sake of upcoming features, but don't bother > stable-backporting, as it's well hidden -- apart from that LD flag, > can be triggered only by GCC LTO which never landed upstream. > > Fixes: fcd38ed0ff26 ("scripts: modpost: fix compilation warning") > Signed-off-by: Alexander Lobakin <alexandr.lobakin@...el.com> > --- Acked-by: Masahiro Yamada <masahiroy@...nel.org> > scripts/mod/modpost.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c > index 6bfa33217914..4648b7afe5cc 100644 > --- a/scripts/mod/modpost.c > +++ b/scripts/mod/modpost.c > @@ -1986,7 +1986,7 @@ static char *remove_dot(char *s) > > if (n && s[n]) { > size_t m = strspn(s + n + 1, "0123456789"); > - if (m && (s[n + m] == '.' || s[n + m] == 0)) > + if (m && (s[n + m + 1] == '.' || s[n + m + 1] == 0)) > s[n] = 0; > > /* strip trailing .lto */ > -- > 2.34.1 > -- Best Regards Masahiro Yamada
Powered by blists - more mailing lists