From:   Nadav Amit <namit@vmware.com>
To:     Dave Hansen <dave.hansen@intel.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>
Subject: Re: [PATCH] x86/kprobes: Fix 1 byte conditional jump target
Thread-Topic: [PATCH] x86/kprobes: Fix 1 byte conditional jump target
Thread-Index: AQHZONzOlqQ9zgLH5EacMBCbCDIQPq7CQ9CAgAAGPYCAADuhAIAAJgkAgADyRgCAAAN3AIAA+40A
Date:   Wed, 8 Feb 2023 06:34:27 +0000
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> On Feb 7, 2023, at 5:33 PM, Dave Hansen <dave.hansen@intel.com> wrote:
>=20
> !! External Email
>=20
> On 2/7/23 07:21, Masami Hiramatsu (Google) wrote:
>>> Nadav, can you update your patch to assign immediate.value directly?
>> BTW, there are many similar casts around there. I'll fix those too.
>> If we need to be more conservative,
>=20
> Let's focus on fixing the known bug first, please.  Cleanups can come lat=
er.

Thank you Dave. That was my take too following your email.

I certainly did not pay attention to the fact that sign extension has alrea=
dy
been done in insn_get_immediate() before Masami pointed it out. So, the com=
ment
in insn_get_immediate() should also be updated to note that the immediate
is sign-*extended* in *all* cases (instead of sign-expanded in most cases. =
:) )

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.