Message-ID: <b1300308-8f29-fa73-5542-25d06925ca84@intel.com>
Date:   Tue, 7 Feb 2023 22:56:48 -0800
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Subject: Re: [PATCH] x86/kprobes: Fix 1 byte conditional jump target
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To:     Nadav Amit <namit@vmware.com>
Cc:     "Masami Hiramatsu (Google)" <mhiramat@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        X86 ML <x86@kernel.org>,
        kernel list <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>
References: <20230204210807.3930-1-namit@vmware.com>
 <a75c134d-8278-b17c-e05e-409b70ad15b0@intel.com>
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 <dc964552-dca7-dd83-52a2-283be7f51555@intel.com>
 <20230207095424.42f4c0147f693a8cef25757c@kernel.org>
 <20230208002132.63b70cb9d6e5badad45fb828@kernel.org>
 <9fb39b3a-2edb-7fd3-2b7c-3a347478083f@intel.com>
 <B790D31A-A0BE-4707-BA01-398B5668C3D8@vmware.com>
From:   Dave Hansen <dave.hansen@intel.com>
In-Reply-To: <B790D31A-A0BE-4707-BA01-398B5668C3D8@vmware.com>
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On 2/7/23 22:34, Nadav Amit wrote:
> As you said, I guess the change you and Masami proposed can be done on top of
> this patch, which is (and was) only intended to fix the bug, and should
> therefore go into 6.2.

Nadav,
	
To fix this issue, you proposed:

	p->ainsn.rel32 = *(s8 *)&insn->immediate.value;

But, this is, um, rather obfuscated and potentially less correct
compared to:

	p->ainsn.rel32 = insn->immediate.value;

I'd appreciate it if you could update your patch to do this simpler
thing and resend, unless there is a strong reason to do what you
originally proposed.