From: Naveen N Rao <naveen@kernel.org>
To: Nicholas Miehlbradt <nicholas@linux.ibm.com>
Cc: elver@google.com, iii@linux.ibm.com,
linux-kernel@vger.kernel.org, npiggin@gmail.com,
linux-mm@kvack.org, glider@google.com, akpm@linux-foundation.org,
kasan-dev@googlegroups.com, linuxppc-dev@lists.ozlabs.org,
dvyukov@google.com
Subject: Re: [PATCH 07/13] powerpc/kprobes: Unpoison instruction in kprobe struct
Date: Fri, 15 Dec 2023 13:21:44 +0530 [thread overview]
Message-ID: <xn274hbvxsfwii6lwis72ntnphiixvcob6hkopn5fygutht3qe@j4sau5ejaxwj> (raw)
In-Reply-To: <20231214055539.9420-8-nicholas@linux.ibm.com>
On Thu, Dec 14, 2023 at 05:55:33AM +0000, Nicholas Miehlbradt wrote:
> KMSAN does not unpoison the ainsn field of a kprobe struct correctly.
> Manually unpoison it to prevent false positives.
>
> Signed-off-by: Nicholas Miehlbradt <nicholas@linux.ibm.com>
> ---
> arch/powerpc/kernel/kprobes.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c
> index b20ee72e873a..1cbec54f2b6a 100644
> --- a/arch/powerpc/kernel/kprobes.c
> +++ b/arch/powerpc/kernel/kprobes.c
> @@ -27,6 +27,7 @@
> #include <asm/sections.h>
> #include <asm/inst.h>
> #include <linux/uaccess.h>
> +#include <linux/kmsan-checks.h>
>
> DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
> DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
> @@ -179,6 +180,7 @@ int arch_prepare_kprobe(struct kprobe *p)
>
> if (!ret) {
> patch_instruction(p->ainsn.insn, insn);
> + kmsan_unpoison_memory(p->ainsn.insn, sizeof(kprobe_opcode_t));
kprobe_opcode_t is u32, but we could be probing a prefixed instruction.
You can pass the instruction length through ppc_inst_len(insn).
- Naveen
next prev parent reply other threads:[~2023-12-15 8:00 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-12-14 5:55 [PATCH 00/13] kmsan: Enable on powerpc Nicholas Miehlbradt
2023-12-14 5:55 ` [PATCH 01/13] kmsan: Export kmsan_handle_dma Nicholas Miehlbradt
2024-02-19 19:37 ` Christophe Leroy
2023-12-14 5:55 ` [PATCH 02/13] hvc: Fix use of uninitialized array in udbg_hvc_putc Nicholas Miehlbradt
2023-12-14 8:36 ` Christophe Leroy
2023-12-21 12:09 ` Michael Ellerman
2023-12-14 5:55 ` [PATCH 03/13] powerpc: Disable KMSAN santitization for prom_init, vdso and purgatory Nicholas Miehlbradt
2023-12-14 5:55 ` [PATCH 04/13] powerpc: Disable CONFIG_DCACHE_WORD_ACCESS when KMSAN is enabled Nicholas Miehlbradt
2023-12-14 8:42 ` Christophe Leroy
2023-12-14 5:55 ` [PATCH 05/13] powerpc: Unpoison buffers populated by hcalls Nicholas Miehlbradt
2023-12-14 5:55 ` [PATCH 06/13] powerpc/pseries/nvram: Unpoison buffer populated by rtas_call Nicholas Miehlbradt
2023-12-14 5:55 ` [PATCH 07/13] powerpc/kprobes: Unpoison instruction in kprobe struct Nicholas Miehlbradt
2023-12-15 7:51 ` Naveen N Rao [this message]
2023-12-14 5:55 ` [PATCH 08/13] powerpc: Unpoison pt_regs Nicholas Miehlbradt
2023-12-14 5:55 ` [PATCH 09/13] powerpc: Disable KMSAN checks on functions which walk the stack Nicholas Miehlbradt
2023-12-14 9:00 ` Christophe Leroy
2024-01-10 4:16 ` Nicholas Miehlbradt
2023-12-15 9:02 ` Aneesh Kumar K.V
2023-12-14 5:55 ` [PATCH 10/13] powerpc: Define KMSAN metadata address ranges for vmalloc and ioremap Nicholas Miehlbradt
2023-12-14 9:17 ` Christophe Leroy
2024-01-10 3:54 ` Nicholas Miehlbradt
2023-12-15 9:27 ` Aneesh Kumar K.V
2023-12-14 5:55 ` [PATCH 11/13] powerpc: Implement architecture specific KMSAN interface Nicholas Miehlbradt
2023-12-14 9:20 ` Christophe Leroy
2023-12-14 5:55 ` [PATCH 12/13] powerpc/string: Add KMSAN support Nicholas Miehlbradt
2023-12-14 9:25 ` Christophe Leroy
2024-01-10 4:09 ` Nicholas Miehlbradt
2023-12-14 5:55 ` [PATCH 13/13] powerpc: Enable KMSAN on powerpc Nicholas Miehlbradt
2023-12-14 9:27 ` Christophe Leroy
2024-02-20 6:39 ` [PATCH 00/13] kmsan: Enable " Christophe Leroy
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=xn274hbvxsfwii6lwis72ntnphiixvcob6hkopn5fygutht3qe@j4sau5ejaxwj \
--to=naveen@kernel.org \
--cc=akpm@linux-foundation.org \
--cc=dvyukov@google.com \
--cc=elver@google.com \
--cc=glider@google.com \
--cc=iii@linux.ibm.com \
--cc=kasan-dev@googlegroups.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=nicholas@linux.ibm.com \
--cc=npiggin@gmail.com \
/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).