From: Borislav Petkov <bp@suse.de>
To: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>,
Thomas Gleixner <tglx@linutronix.de>,
"H. Peter Anvin" <hpa@zytor.com>,
Andy Lutomirski <luto@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Andrew Morton <akpm@linux-foundation.org>,
Brian Gerst <brgerst@gmail.com>,
Chris Metcalf <cmetcalf@mellanox.com>,
Dave Hansen <dave.hansen@linux.intel.com>,
Paolo Bonzini <pbonzini@redhat.com>,
Masami Hiramatsu <mhiramat@kernel.org>,
Huang Rui <ray.huang@amd.com>, Jiri Slaby <jslaby@suse.cz>,
Jonathan Corbet <corbet@lwn.net>,
"Michael S. Tsirkin" <mst@redhat.com>,
Paul Gortmaker <paul.gortmaker@windriver.com>,
Vlastimil Babka <vbabka@suse.cz>, Chen Yucong <slaoub@gmail.com>,
Alexandre Julliard <julliard@winehq.org>,
Stas Sergeev <stsp@list.ru>, Fenghua Yu <fenghua.yu@intel.com>,
"Ravi V. Shankar" <ravi.v.shankar@intel.com>,
Shuah Khan <shuah@kernel.org>,
linux-kernel@vger.kernel.org, x86@kernel.org,
linux-msdos@vger.kernel.org, wine-devel@winehq.org,
Adam Buchbinder <adam.buchbinder@gmail.com>,
Colin Ian King <colin.king@canonical.com>,
Lorenzo Stoakes <lstoakes@gmail.com>,
Qiaowei Ren <qiaowei.ren@intel.com>,
Arnaldo Carvalho de Melo <acme@redhat.com>,
Adrian Hunter <adrian.hunter@intel.com>,
Kees Cook <keescook@chromium.org>,
Thomas Garnier <thgarnie@google.com>,
Dmitry Vyukov <dvyukov@google.com>
Subject: Re: [v6 PATCH 04/21] x86/mpx, x86/insn: Relocate insn util functions to a new insn-kernel
Date: Wed, 12 Apr 2017 12:03:08 +0200 [thread overview]
Message-ID: <20170412100308.uuai3hf3l2fsavhb@pd.tnic> (raw)
In-Reply-To: <20170308003254.27833-5-ricardo.neri-calderon@linux.intel.com>
On Tue, Mar 07, 2017 at 04:32:37PM -0800, Ricardo Neri wrote:
> Other kernel submodules can benefit from using the utility functions
> defined in mpx.c to obtain the addresses and values of operands contained
> in the general purpose registers. An instance of this is the emulation code
> used for instructions protected by the Intel User-Mode Instruction
> Prevention feature.
>
> Thus, these functions are relocated to a new insn-eval.c file. The reason
> to not relocate these utilities into insn.c is that the latter solely
> analyses instructions given by a struct insn without any knowledge of the
> meaning of the values of instruction operands. This new utility insn-
> eval.c aims to be used to resolve effective and userspace linear addresses
> based on the contents of the instruction operands as well as the contents
> of pt_regs structure.
>
> These utilities come with a separate header. This is to avoid taking insn.c
> out of sync from the instructions decoders under tools/obj and tools/perf.
> This also avoids adding cumbersome #ifdef's for the #include'd files
> required to decode instructions in a kernel context.
>
> Functions are simply relocated. There are not functional or indentation
> changes.
...
> + case REG_TYPE_BASE:
> + regno = X86_SIB_BASE(insn->sib.value);
> + /*
> + * If mod is 0 and register R/EBP (regno=5) is indicated in the
> + * base part of the SIB byte, the value of such register should
> + * not be used in the address computation. Also, a 32-bit
> + * displacement is expected in this case; the instruction
> + * decoder takes care of it. This is true for both R13 and
> + * R/EBP as REX.B will not be decoded.
> + */
> + if (regno == 5 && X86_MODRM_MOD(insn->modrm.value) == 0)
> + return -EDOM;
> +
> + if (X86_REX_B(insn->rex_prefix.value))
> + regno += 8;
> + break;
> +
> + default:
> + pr_err("invalid register type");
> + BUG();
WARNING: Avoid crashing the kernel - try using WARN_ON & recovery code rather than BUG() or BUG_ON()
#211: FILE: arch/x86/lib/insn-eval.c:90:
+ BUG();
And checkpatch is kinda right. We need to warn here, not explode. Oh and
that function returns negative values on error...
Please change that with a patch ontop of the move.
Thanks.
--
Regards/Gruss,
Boris.
SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
--
next prev parent reply other threads:[~2017-04-12 10:03 UTC|newest]
Thread overview: 112+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-03-08 0:32 [v6 PATCH 00/21] x86: Enable User-Mode Instruction Prevention Ricardo Neri
2017-03-08 0:32 ` [v6 PATCH 01/21] x86/mpx: Use signed variables to compute effective addresses Ricardo Neri
2017-04-11 21:56 ` Borislav Petkov
2017-04-26 1:40 ` Ricardo Neri
2017-03-08 0:32 ` [v6 PATCH 02/21] x86/mpx: Do not use SIB index if index points to R/ESP Ricardo Neri
2017-04-11 11:31 ` Borislav Petkov
2017-04-26 1:39 ` Ricardo Neri
2017-03-08 0:32 ` [v6 PATCH 03/21] x86/mpx: Do not use R/EBP as base in the SIB byte with Mod = 0 Ricardo Neri
2017-04-11 22:08 ` Borislav Petkov
2017-04-26 2:04 ` Ricardo Neri
2017-04-26 8:05 ` Borislav Petkov
2017-04-27 22:49 ` Ricardo Neri
2017-03-08 0:32 ` [v6 PATCH 04/21] x86/mpx, x86/insn: Relocate insn util functions to a new insn-kernel Ricardo Neri
2017-04-12 10:03 ` Borislav Petkov [this message]
2017-04-26 2:05 ` Ricardo Neri
2017-03-08 0:32 ` [v6 PATCH 05/21] x86/insn-eval: Add utility functions to get register offsets Ricardo Neri
2017-04-12 16:28 ` Borislav Petkov
2017-04-26 18:13 ` Ricardo Neri
2017-04-28 10:40 ` Borislav Petkov
2017-03-08 0:32 ` [v6 PATCH 06/21] x86/insn-eval: Add utility functions to get segment selector Ricardo Neri
2017-04-18 9:42 ` Borislav Petkov
2017-04-26 20:44 ` Ricardo Neri
2017-04-26 20:47 ` Ricardo Neri
2017-04-30 17:15 ` Borislav Petkov
2017-05-05 18:31 ` Ricardo Neri
2017-03-08 0:32 ` [v6 PATCH 07/21] x86/insn-eval: Add utility function to get segment descriptor Ricardo Neri
2017-04-19 10:26 ` Borislav Petkov
2017-04-26 21:51 ` Ricardo Neri
2017-05-04 11:02 ` Borislav Petkov
2017-05-12 2:13 ` Ricardo Neri
2017-05-15 17:27 ` Borislav Petkov
2017-03-08 0:32 ` [v6 PATCH 08/21] x86/insn-eval: Add utility function to get segment descriptor base address Ricardo Neri
2017-04-20 8:25 ` Borislav Petkov
2017-04-26 22:37 ` Ricardo Neri
2017-05-05 17:19 ` Borislav Petkov
2017-05-12 2:09 ` Ricardo Neri
2017-04-26 22:52 ` Ricardo Neri
2017-05-05 17:28 ` Borislav Petkov
2017-05-12 2:06 ` Ricardo Neri
2017-03-08 0:32 ` [v6 PATCH 09/21] x86/insn-eval: Add functions to get default operand and address sizes Ricardo Neri
2017-04-20 13:06 ` Borislav Petkov
2017-04-27 1:07 ` Ricardo Neri
2017-03-08 0:32 ` [v6 PATCH 10/21] x86/insn-eval: Do not use R/EBP as base if mod in ModRM is zero Ricardo Neri
2017-04-21 10:52 ` Borislav Petkov
2017-04-27 1:29 ` Ricardo Neri
2017-05-07 17:20 ` Borislav Petkov
2017-05-12 1:57 ` Ricardo Neri
2017-03-08 0:32 ` [v6 PATCH 11/21] insn/eval: Incorporate segment base in address computation Ricardo Neri
2017-04-21 14:55 ` Borislav Petkov
2017-04-27 1:31 ` Ricardo Neri
2017-03-08 0:32 ` [v6 PATCH 12/21] x86/insn: Support both signed 32-bit and 64-bit effective addresses Ricardo Neri
2017-04-25 13:51 ` Borislav Petkov
2017-04-27 3:33 ` Ricardo Neri
2017-05-08 11:42 ` Borislav Petkov
2017-05-12 1:55 ` Ricardo Neri
2017-03-08 0:32 ` [v6 PATCH 13/21] x86/insn-eval: Add support to resolve 16-bit addressing encodings Ricardo Neri
2017-03-08 0:32 ` [v6 PATCH 14/21] x86/insn-eval: Add wrapper function for 16-bit and 32-bit address encodings Ricardo Neri
2017-03-08 0:32 ` [v6 PATCH 15/21] x86/mm: Relocate page fault error codes to traps.h Ricardo Neri
2017-03-08 16:08 ` Andy Lutomirski
2017-03-08 0:32 ` [v6 PATCH 16/21] x86/cpufeature: Add User-Mode Instruction Prevention definitions Ricardo Neri
2017-03-08 0:32 ` [v6 PATCH 17/21] x86: Add emulation code for UMIP instructions Ricardo Neri
2017-03-08 0:32 ` [v6 PATCH 18/21] x86/umip: Force a page fault when unable to copy emulated result to user Ricardo Neri
2017-03-08 0:32 ` [v6 PATCH 19/21] x86/traps: Fixup general protection faults caused by UMIP Ricardo Neri
2017-03-08 15:54 ` Andy Lutomirski
2017-03-08 0:32 ` [v6 PATCH 20/21] x86: Enable User-Mode Instruction Prevention Ricardo Neri
2017-03-08 0:32 ` [v6 PATCH 21/21] selftests/x86: Add tests for " Ricardo Neri
2017-03-08 15:56 ` Andy Lutomirski
2017-03-10 23:38 ` Ricardo Neri
2017-03-08 14:08 ` [v6 PATCH 00/21] x86: Enable " Stas Sergeev
2017-03-08 16:06 ` Andy Lutomirski
2017-03-08 16:29 ` Stas Sergeev
2017-03-08 16:46 ` Andy Lutomirski
2017-03-08 16:53 ` Stas Sergeev
2017-03-09 1:11 ` Ricardo Neri
2017-03-09 22:05 ` Stas Sergeev
2017-03-10 2:41 ` Andy Lutomirski
2017-03-10 10:30 ` Stas Sergeev
2017-03-10 21:04 ` Andy Lutomirski
2017-03-10 21:37 ` Stas Sergeev
2017-03-09 1:15 ` Ricardo Neri
2017-03-09 22:10 ` Stas Sergeev
2017-03-10 2:39 ` Andy Lutomirski
2017-03-10 11:33 ` Stas Sergeev
2017-03-10 14:17 ` Andy Lutomirski
2017-03-11 1:22 ` Ricardo Neri
2017-03-10 23:59 ` Ricardo Neri
2017-03-13 21:25 ` Stas Sergeev
2017-03-27 23:46 ` Ricardo Neri
2017-03-28 9:38 ` Stas Sergeev
2017-03-29 4:38 ` Ricardo Neri
2017-03-29 20:55 ` Stas Sergeev
2017-03-30 5:14 ` Ricardo Neri
2017-03-30 10:10 ` Stas Sergeev
2017-03-31 1:33 ` Ricardo Neri
2017-03-31 14:11 ` Alexandre Julliard
2017-03-31 21:26 ` Stas Sergeev
2017-04-01 2:18 ` Andy Lutomirski
2017-04-04 2:02 ` Ricardo Neri
2017-04-04 6:08 ` Alexandre Julliard
2017-04-01 13:08 ` Stas Sergeev
2017-04-01 17:49 ` H. Peter Anvin
2017-04-02 15:52 ` Andy Lutomirski
2017-04-04 9:59 ` Stas Sergeev
2017-04-04 2:05 ` Ricardo Neri
2017-04-04 8:03 ` Stas Sergeev
2017-03-10 23:58 ` Ricardo Neri
2017-03-09 0:46 ` Ricardo Neri
2017-03-09 22:01 ` Stas Sergeev
2017-03-10 23:47 ` Ricardo Neri
2017-03-10 23:58 ` Stas Sergeev
2017-03-11 0:13 ` Ricardo Neri
2017-03-08 16:07 ` Andy Lutomirski
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=20170412100308.uuai3hf3l2fsavhb@pd.tnic \
--to=bp@suse.de \
--cc=acme@redhat.com \
--cc=adam.buchbinder@gmail.com \
--cc=adrian.hunter@intel.com \
--cc=akpm@linux-foundation.org \
--cc=brgerst@gmail.com \
--cc=cmetcalf@mellanox.com \
--cc=colin.king@canonical.com \
--cc=corbet@lwn.net \
--cc=dave.hansen@linux.intel.com \
--cc=dvyukov@google.com \
--cc=fenghua.yu@intel.com \
--cc=hpa@zytor.com \
--cc=jslaby@suse.cz \
--cc=julliard@winehq.org \
--cc=keescook@chromium.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-msdos@vger.kernel.org \
--cc=lstoakes@gmail.com \
--cc=luto@kernel.org \
--cc=mhiramat@kernel.org \
--cc=mingo@redhat.com \
--cc=mst@redhat.com \
--cc=paul.gortmaker@windriver.com \
--cc=pbonzini@redhat.com \
--cc=peterz@infradead.org \
--cc=qiaowei.ren@intel.com \
--cc=ravi.v.shankar@intel.com \
--cc=ray.huang@amd.com \
--cc=ricardo.neri-calderon@linux.intel.com \
--cc=shuah@kernel.org \
--cc=slaoub@gmail.com \
--cc=stsp@list.ru \
--cc=tglx@linutronix.de \
--cc=thgarnie@google.com \
--cc=vbabka@suse.cz \
--cc=wine-devel@winehq.org \
--cc=x86@kernel.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).