linux-kernel - [PATCH v3 0/2] power_supply: Fix Oops from NULL pointer dereference from wakeup_source

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <cover.1385138418.git.shuah.kh@samsung.com>
Date:	Fri, 22 Nov 2013 10:54:27 -0700
From:	Shuah Khan <shuah.kh@...sung.com>
To:	anton@...msg.org, dwmw2@...radead.org, rostedt@...dmis.org,
	fweisbec@...il.com, mingo@...hat.com, rjw@...ysocki.net,
	gregkh@...uxfoundation.org
Cc:	Shuah Khan <shuah.kh@...sung.com>, linux-kernel@...r.kernel.org,
	shuahkhan@...il.com
Subject: [PATCH v3 0/2] power_supply: Fix Oops from NULL pointer dereference from wakeup_source_activate

power_supply_register() calls device_init_wakeup() to register a wakeup
source before initializing dev_name. As a result, device_wakeup_enable()
end up registering wakeup source with a null name when wakeup_source_register()
gets called with dev_name(dev) which is null at the time.

device_wakeup_enable() uses dev_name(dev) as the wakeup source name.
When it gets called with a device with its name not yet set, ws structure
with ws->name = NULL gets created.

When kernel is booted with wakeup_source_activate enabled, it will panic
when the trace point code tries to dereference ws->name. Registering a
a wakeup source without a name should be possible.

This patch series fixes power_supply_register() to initialize the device name
prior to calling device_init_wakeup() and fixes tracing infrastructure to be
more robust in handling null strings in __assign_string() and __string(). With
this change null string is handled gracefully and replacing it with "(null)"
when trace is generated.

These two patches are not dependent, I left them as a series since the original
discussion started the fixes grouped in a series.

power_supply patch - no changes since series patch v1, other than including
Acked-by from Greg and Anton. Also added stable tag.

Second patch now is the fix to tracepoint infrastructure routines
__assign_string() and __string(). This will address the problem at the tracing
infrastructure level which is better than fixing individual tracepoint code.

These patches can be applied independently with no ill effects. I included
the trace for the wakeup_source_activate trace output in the change logs for
both patches.

Shuah Khan (2):
  power_supply: Fix Oops from NULL pointer dereference from
    wakeup_source_activate
  tracing: Fix Oops from NULL pointer dereference from __assign_str

 drivers/power/power_supply_core.c | 12 ++++++------
 include/trace/ftrace.h            |  7 +++++--
 2 files changed, 11 insertions(+), 8 deletions(-)

-- 
1.8.3.2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/