From: Rajat Jain <rajatja@google.com>
To: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Andreas Noever <andreas.noever@gmail.com>,
Michael Jamet <michael.jamet@intel.com>,
Yehezkel Bernat <yehezkelshb@gmail.com>,
linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
rajatxjain@gmail.com
Subject: Re: [PATCH v2] thunderbolt: For dev authorization changes, include the actual event in udev change notification
Date: Fri, 30 Jul 2021 16:55:34 -0700 [thread overview]
Message-ID: <CACK8Z6GAZrk1XLamVp1Rh2uLYjfmaprAj==D4KR190Jp4dn5wg@mail.gmail.com> (raw)
In-Reply-To: <YP67VTcyFhro9wyX@lahna>
On Mon, Jul 26, 2021 at 6:40 AM Mika Westerberg
<mika.westerberg@linux.intel.com> wrote:
>
> Hi Rajat,
>
> On Fri, Jul 23, 2021 at 05:41:58PM -0700, Rajat Jain wrote:
> > (fixing the typo in the email ID for Greg).
> >
> > On Fri, Jul 23, 2021 at 5:40 PM Rajat Jain <rajatja@google.com> wrote:
> > >
> > > For security, we would like to monitor and track when the thunderbolt
> > > devices are authorized and deauthorized (i.e. when the thunderbolt sysfs
> > > "authorized" attribute changes). Currently the userspace gets a udev
> > > change notification when there is a change, but the state may have
> > > changed (again) by the time we look at the authorized attribute in
> > > sysfs. So an authorization event may go unnoticed. Thus make it easier
> > > by informing the actual change (new value of authorized attribute) in
> > > the udev change notification.
> > >
> > > The change is included as a key value "authorized=<val>" where <val>
> > > is the new value of sysfs attribute "authorized", and is described at
> > > Documentation/ABI/testing/sysfs-bus-thunderbolt under
> > > /sys/bus/thunderbolt/devices/.../authorized
>
> Looking good, a couple of minor nits below.
>
> > >
> > > Signed-off-by: Rajat Jain <rajatja@google.com>
> > > ---
> > > drivers/thunderbolt/switch.c | 8 ++++++--
> > > 1 file changed, 6 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
> > > index 83b1ef3d5d03..382128dfbdee 100644
> > > --- a/drivers/thunderbolt/switch.c
> > > +++ b/drivers/thunderbolt/switch.c
> > > @@ -1499,6 +1499,7 @@ static ssize_t authorized_show(struct device *dev,
> > > static int disapprove_switch(struct device *dev, void *not_used)
> > > {
> > > struct tb_switch *sw;
> > > + char *envp[] = { "AUTHORIZED=0", NULL };
>
> Can you move arrange this to be before sw, like:
Done.
>
> char *envp[] = { "AUTHORIZED=0", NULL };
> struct tb_switch *sw;
>
> > >
> > > sw = tb_to_switch(dev);
> > > if (sw && sw->authorized) {
> > > @@ -1514,7 +1515,7 @@ static int disapprove_switch(struct device *dev, void *not_used)
> > > return ret;
> > >
> > > sw->authorized = 0;
> > > - kobject_uevent(&sw->dev.kobj, KOBJ_CHANGE);
> > > + kobject_uevent_env(&sw->dev.kobj, KOBJ_CHANGE, envp);
> > > }
> > >
> > > return 0;
> > > @@ -1523,6 +1524,8 @@ static int disapprove_switch(struct device *dev, void *not_used)
> > > static int tb_switch_set_authorized(struct tb_switch *sw, unsigned int val)
> > > {
> > > int ret = -EINVAL;
> > > + char envp_string[13];
> > > + char *envp[] = { envp_string, NULL };
>
> Ditto.
Done. I still needed to define envp_string before envp (because it is
used in initialization).
I sent out a v3 with these changes.
Thanks,
Rajat
>
> > >
> > > if (!mutex_trylock(&sw->tb->lock))
> > > return restart_syscall();
> > > @@ -1560,7 +1563,8 @@ static int tb_switch_set_authorized(struct tb_switch *sw, unsigned int val)
> > > if (!ret) {
> > > sw->authorized = val;
> > > /* Notify status change to the userspace */
> > > - kobject_uevent(&sw->dev.kobj, KOBJ_CHANGE);
> > > + sprintf(envp_string, "AUTHORIZED=%u", sw->authorized);
> > > + kobject_uevent_env(&sw->dev.kobj, KOBJ_CHANGE, envp);
> > > }
> > >
> > > unlock:
> > > --
> > > 2.32.0.432.gabb21c7263-goog
> > >
next prev parent reply other threads:[~2021-07-30 23:56 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-24 0:40 [PATCH v2] thunderbolt: For dev authorization changes, include the actual event in udev change notification Rajat Jain
2021-07-24 0:41 ` Rajat Jain
2021-07-26 13:40 ` Mika Westerberg
2021-07-30 23:55 ` Rajat Jain [this message]
2021-07-24 6:48 ` Greg KH
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='CACK8Z6GAZrk1XLamVp1Rh2uLYjfmaprAj==D4KR190Jp4dn5wg@mail.gmail.com' \
--to=rajatja@google.com \
--cc=andreas.noever@gmail.com \
--cc=gregkh@linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=michael.jamet@intel.com \
--cc=mika.westerberg@linux.intel.com \
--cc=rajatxjain@gmail.com \
--cc=yehezkelshb@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).