From mboxrd@z Thu Jan 1 00:00:00 1970 From: Scott James Remnant Date: Tue, 25 Aug 2009 11:58:59 +0000 Subject: Re: [security] Race condition in udev Message-Id: <1251201539.4175.66.camel@quest> MIME-Version: 1 Content-Type: multipart/mixed; boundary="=-Y3fAq4LsP4kyl1w+dT8T" List-Id: References: <20090821102407.GA29609@florz.florz.dyndns.org> In-Reply-To: <20090821102407.GA29609@florz.florz.dyndns.org> To: linux-hotplug@vger.kernel.org --=-Y3fAq4LsP4kyl1w+dT8T Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On Tue, 2009-08-25 at 13:32 +0200, Florian Zumbiehl wrote: > > reading some of the source of udev, I noticed what I would suspect to b= e a > [...] >=20 > could someone possibly explain to me why there is that special codepath > for cases where the device node does already exist, so I can write a > patch that's not gonna break other functionality? >=20 For example, when using devtmpfs; in which case the device nodes already exist. Or when updating devices like /dev/null which are created before udevd is started by the init script when not using devtmpfs. Or when racing with devmapper which creates /dev/mapper/foo devices at basically the same time as udev. Scott --=20 Scott James Remnant scott@canonical.com --=-Y3fAq4LsP4kyl1w+dT8T Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iEYEABECAAYFAkqT0gMACgkQSnQiFMl4yK7ebQCgrJFMliPvS/XHh1rWJVixbmZv SCMAoJhxX5/Vuidudypt5zdrB7sX6FF3 =cAJ4 -----END PGP SIGNATURE----- --=-Y3fAq4LsP4kyl1w+dT8T--