Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753247AbbGOQyd (ORCPT ); Wed, 15 Jul 2015 12:54:33 -0400 Received: from mx1.redhat.com ([209.132.183.28]:33834 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753167AbbGOQy3 (ORCPT ); Wed, 15 Jul 2015 12:54:29 -0400 Date: Wed, 15 Jul 2015 11:28:17 -0400 From: Benjamin Tissoires To: cpaul@redhat.com Cc: linux-kernel@vger.kernel.org, linux-input@vger.kernel.org, Hans de Goede , Dmitry Torokhov , Andreas Mohr Subject: Re: [PATCH v5] i8042: Add unmask_kbd_data option Message-ID: <20150715152817.GA16611@mail.corp.redhat.com> References: <20150627203543.GA31870@rhlx01.hs-esslingen.de> <1435852008-4509-1-git-send-email-cpaul@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1435852008-4509-1-git-send-email-cpaul@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7938 Lines: 226 On Jul 02 2015 or thereabouts, cpaul@redhat.com wrote: > From: Stephen Chandler Paul > > A big problem with the current i8042 debugging option is that it outputs > data going to and from the keyboard by default. As a result, many dmesg > logs uploaded by users will unintentionally contain sensitive information > such as their password, as such it's probably a good idea not to output > data coming from the keyboard unless specifically enabled by the user. > > Signed-off-by: Stephen Chandler Paul > --- FWIW, in case you are missing my input Dmitry: Reviewed-by: Benjamin Tissoires Thanks everyone involved in this process! Cheers, Benjamin > Changes > * Fix incorrect option name in MODULE_PARM_DESC() (I have no idea how that > happened in the first place) > * Replaced the description with one of the suggestions given by Andreas > * Rename debug_kbd to unmask_kbd_data > * Improve description in Documentation/kernel-parameters.txt > > Documentation/kernel-parameters.txt | 4 ++++ > drivers/input/serio/i8042.c | 43 +++++++++++++++++++++++++++++++++---- > drivers/input/serio/i8042.h | 13 +++++++++++ > drivers/input/serio/serio.c | 4 +--- > include/linux/serio.h | 2 ++ > 5 files changed, 59 insertions(+), 7 deletions(-) > > diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt > index ae44749..352a5f1 100644 > --- a/Documentation/kernel-parameters.txt > +++ b/Documentation/kernel-parameters.txt > @@ -1304,6 +1304,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted. > , > > i8042.debug [HW] Toggle i8042 debug mode > + i8042.unmask_kbd_data > + [HW] Enable printing of interrupt data from the KBD port > + (disabled by default, and as a pre-condition > + requires that i8042.debug=1 be enabled) > i8042.direct [HW] Put keyboard port into non-translated mode > i8042.dumbkbd [HW] Pretend that controller can only read data from > keyboard and cannot control its state > diff --git a/drivers/input/serio/i8042.c b/drivers/input/serio/i8042.c > index cb5ece7..e6d1529 100644 > --- a/drivers/input/serio/i8042.c > +++ b/drivers/input/serio/i8042.c > @@ -88,6 +88,10 @@ MODULE_PARM_DESC(nopnp, "Do not use PNP to detect controller settings"); > static bool i8042_debug; > module_param_named(debug, i8042_debug, bool, 0600); > MODULE_PARM_DESC(debug, "Turn i8042 debugging mode on and off"); > + > +static bool i8042_unmask_kbd_data; > +module_param_named(unmask_kbd_data, i8042_unmask_kbd_data, bool, 0600); > +MODULE_PARM_DESC(unmask_kbd_data, "Unconditional enable (may reveal sensitive data) of normally sanitize-filtered kbd data traffic debug log [pre-condition: i8042.debug=1 enabled]"); > #endif > > static bool i8042_bypass_aux_irq_test; > @@ -116,6 +120,7 @@ struct i8042_port { > struct serio *serio; > int irq; > bool exists; > + bool driver_bound; > signed char mux; > }; > > @@ -133,6 +138,7 @@ static bool i8042_kbd_irq_registered; > static bool i8042_aux_irq_registered; > static unsigned char i8042_suppress_kbd_ack; > static struct platform_device *i8042_platform_device; > +static struct notifier_block i8042_kbd_bind_notifier_block; > > static irqreturn_t i8042_interrupt(int irq, void *dev_id); > static bool (*i8042_platform_filter)(unsigned char data, unsigned char str, > @@ -528,10 +534,10 @@ static irqreturn_t i8042_interrupt(int irq, void *dev_id) > port = &i8042_ports[port_no]; > serio = port->exists ? port->serio : NULL; > > - dbg("%02x <- i8042 (interrupt, %d, %d%s%s)\n", > - data, port_no, irq, > - dfl & SERIO_PARITY ? ", bad parity" : "", > - dfl & SERIO_TIMEOUT ? ", timeout" : ""); > + filter_dbg(port->driver_bound, data, "<- i8042 (interrupt, %d, %d%s%s)\n", > + port_no, irq, > + dfl & SERIO_PARITY ? ", bad parity" : "", > + dfl & SERIO_TIMEOUT ? ", timeout" : ""); > > filtered = i8042_filter(data, str, serio); > > @@ -1438,6 +1444,29 @@ static int __init i8042_setup_kbd(void) > return error; > } > > +static int i8042_kbd_bind_notifier(struct notifier_block *nb, > + unsigned long action, void *data) > +{ > + struct device *dev = data; > + struct serio *serio = to_serio_port(dev); > + struct i8042_port *port = serio->port_data; > + > + if (serio != i8042_ports[I8042_KBD_PORT_NO].serio) > + return 0; > + > + switch (action) { > + case BUS_NOTIFY_BOUND_DRIVER: > + port->driver_bound = true; > + break; > + > + case BUS_NOTIFY_UNBOUND_DRIVER: > + port->driver_bound = false; > + break; > + } > + > + return 0; > +} > + > static int __init i8042_probe(struct platform_device *dev) > { > int error; > @@ -1507,6 +1536,10 @@ static struct platform_driver i8042_driver = { > .shutdown = i8042_shutdown, > }; > > +static struct notifier_block i8042_kbd_bind_notifier_block = { > + .notifier_call = i8042_kbd_bind_notifier, > +}; > + > static int __init i8042_init(void) > { > struct platform_device *pdev; > @@ -1528,6 +1561,7 @@ static int __init i8042_init(void) > goto err_platform_exit; > } > > + bus_register_notifier(&serio_bus, &i8042_kbd_bind_notifier_block); > panic_blink = i8042_panic_blink; > > return 0; > @@ -1543,6 +1577,7 @@ static void __exit i8042_exit(void) > platform_driver_unregister(&i8042_driver); > i8042_platform_exit(); > > + bus_unregister_notifier(&serio_bus, &i8042_kbd_bind_notifier_block); > panic_blink = NULL; > } > > diff --git a/drivers/input/serio/i8042.h b/drivers/input/serio/i8042.h > index fc080be..1db0a40 100644 > --- a/drivers/input/serio/i8042.h > +++ b/drivers/input/serio/i8042.h > @@ -73,6 +73,17 @@ static unsigned long i8042_start_time; > printk(KERN_DEBUG KBUILD_MODNAME ": [%d] " format, \ > (int) (jiffies - i8042_start_time), ##arg); \ > } while (0) > + > +#define filter_dbg(filter, data, format, args...) \ > + do { \ > + if (!i8042_debug) \ > + break; \ > + \ > + if (!filter || i8042_unmask_kbd_data) \ > + dbg("%02x " format, data, ##args); \ > + else \ > + dbg("** " format, ##args); \ > + } while (0) > #else > #define dbg_init() do { } while (0) > #define dbg(format, arg...) \ > @@ -80,6 +91,8 @@ static unsigned long i8042_start_time; > if (0) \ > printk(KERN_DEBUG pr_fmt(format), ##arg); \ > } while (0) > + > +#define filter_dbg(filter, data, format, args...) do { } while (0) > #endif > > #endif /* _I8042_H */ > diff --git a/drivers/input/serio/serio.c b/drivers/input/serio/serio.c > index a05a517..63422d2 100644 > --- a/drivers/input/serio/serio.c > +++ b/drivers/input/serio/serio.c > @@ -49,8 +49,6 @@ static DEFINE_MUTEX(serio_mutex); > > static LIST_HEAD(serio_list); > > -static struct bus_type serio_bus; > - > static void serio_add_port(struct serio *serio); > static int serio_reconnect_port(struct serio *serio); > static void serio_disconnect_port(struct serio *serio); > @@ -1017,7 +1015,7 @@ irqreturn_t serio_interrupt(struct serio *serio, > } > EXPORT_SYMBOL(serio_interrupt); > > -static struct bus_type serio_bus = { > +struct bus_type serio_bus = { > .name = "serio", > .drv_groups = serio_driver_groups, > .match = serio_bus_match, > diff --git a/include/linux/serio.h b/include/linux/serio.h > index 9f779c7..df4ab5d 100644 > --- a/include/linux/serio.h > +++ b/include/linux/serio.h > @@ -18,6 +18,8 @@ > #include > #include > > +extern struct bus_type serio_bus; > + > struct serio { > void *port_data; > > -- > 2.4.3 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/