Date:   Fri, 24 Dec 2021 10:14:46 -0300
From:   Bruno Meneguele <bmeneg@redhat.com>
To:     Mimi Zohar <zohar@linux.ibm.com>
Cc:     linux-integrity@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] ima: silence measurement list hexdump during kexec
Message-ID: <YcXHxgP1w2Us72bS@glitch>
References: <20211222191623.376174-1-bmeneg@redhat.com>
 <31d71e1957e84d2440f41d43d2570b112e91a27b.camel@linux.ibm.com>
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On Wed, Dec 22, 2021 at 05:13:56PM -0500, Mimi Zohar wrote:
> Hi Bruno,
>=20
> On Wed, 2021-12-22 at 16:16 -0300, Bruno Meneguele wrote:
> > The measurement list is dumped during a soft reset (kexec) through the =
call
> > to "print_hex_dump(KERN_DEBUG, ...)", which ignores the DEBUG build fla=
g.
> > Instead, use "print_hex_dump_debug(...)", honoring the build flag.
> >=20
> > Signed-off-by: Bruno Meneguele <bmeneg@redhat.com>
>=20
> The patch description needs to at least explain why using
> print_hex_dump() isn't sufficent.   Look at how print_hex_dump() is
> defined.  Based on whether CONFIG_DYNAMIC_DEBUG is enabled, different
> functions are used.

Sending the v2 in a sec :)

Thanks Mimi

>=20
> Mimi
>=20
> > ---
> >  security/integrity/ima/ima_kexec.c | 6 +++---
> >  1 file changed, 3 insertions(+), 3 deletions(-)
> >=20
> > diff --git a/security/integrity/ima/ima_kexec.c b/security/integrity/im=
a/ima_kexec.c
> > index f799cc278a9a..13753136f03f 100644
> > --- a/security/integrity/ima/ima_kexec.c
> > +++ b/security/integrity/ima/ima_kexec.c
> > @@ -61,9 +61,9 @@ static int ima_dump_measurement_list(unsigned long *b=
uffer_size, void **buffer,
> >  	}
> >  	memcpy(file.buf, &khdr, sizeof(khdr));
> > =20
> > -	print_hex_dump(KERN_DEBUG, "ima dump: ", DUMP_PREFIX_NONE,
> > -			16, 1, file.buf,
> > -			file.count < 100 ? file.count : 100, true);
> > +	print_hex_dump_debug("ima dump: ", DUMP_PREFIX_NONE, 16, 1,
> > +			     file.buf, file.count < 100 ? file.count : 100,
> > +			     true);
> > =20
> >  	*buffer_size =3D file.count;
> >  	*buffer =3D file.buf;
>=20
>=20

--=20
bmeneg=20
PGP Key: http://bmeneg.com/pubkey.txt

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