From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755347Ab3KUBlJ (ORCPT ); Wed, 20 Nov 2013 20:41:09 -0500 Received: from qmta11.emeryville.ca.mail.comcast.net ([76.96.27.211]:49751 "EHLO qmta11.emeryville.ca.mail.comcast.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755178Ab3KUBk6 (ORCPT ); Wed, 20 Nov 2013 20:40:58 -0500 From: Shuah Khan To: len.brown@intel.com, pavel@ucw.cz, rjw@rjwysocki.net, gregkh@linuxfoundation.org, anton@enomsg.org, dwmw2@infradead.org Cc: Shuah Khan , linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, shuahkhan@gmail.com, stable@vger.kernel.org Subject: [PATCH 2/2] PM: Fix Oops from NULL pointer dereference in wakeup_source_activate Date: Wed, 20 Nov 2013 18:40:50 -0700 Message-Id: <43b305b56bbbfc82b2684919e2d1ba2bd50fecae.1384990612.git.shuah.kh@samsung.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. 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. Fix wakeup_source_activate tracepoint to check for null name and handle it gracefully by just using "(no name)" as the name string for the source. Fixes: commit 6791e36c4a40e8930e08669e60077eea6770c429 Trace after the change: bash-2008 [000] d... 610.307262: wakeup_source_activate: (no name) state=0x20001 kworker/0:0-2000 [000] d... 610.307287: wakeup_source_deactivate: (no name) state=0x30000 Oops message: [ 819.769934] device: 'BAT1': device_add [ 819.770078] PM: Adding info for No Bus:BAT1 [ 819.770235] BUG: unable to handle kernel NULL pointer dereference at (null) [ 819.770435] IP: [] skip_spaces+0x30/0x30 [ 819.770572] PGD 3efd90067 PUD 3eff61067 PMD 0 [ 819.770716] Oops: 0000 [#1] SMP [ 819.770829] Modules linked in: arc4 iwldvm mac80211 x86_pkg_temp_thermal coretemp kvm_intel joydev i915 kvm uvcvideo ghash_clmulni_intel videobuf2_vmalloc aesni_intel videobuf2_memops videobuf2_core aes_x86_64 ablk_helper cryptd videodev iwlwifi lrw rfcomm gf128mul glue_helper bnep btusb media bluetooth parport_pc hid_generic ppdev snd_hda_codec_hdmi drm_kms_helper snd_hda_codec_realtek cfg80211 drm tpm_infineon samsung_laptop snd_hda_intel usbhid snd_hda_codec hid snd_hwdep snd_pcm microcode snd_page_alloc snd_timer psmouse i2c_algo_bit lpc_ich tpm_tis video wmi mac_hid serio_raw ext2 lp parport r8169 mii [ 819.771802] CPU: 0 PID: 2167 Comm: bash Not tainted 3.12.0+ #25 [ 819.771876] Hardware name: SAMSUNG ELECTRONICS CO., LTD. 900X3C/900X3D/900X4C/900X4D/SAMSUNG_NP1234567890, BIOS P03AAC 07/12/2012 [ 819.772022] task: ffff88002e6ddcc0 ti: ffff8804015ca000 task.ti: ffff8804015ca000 [ 819.772119] RIP: 0010:[] [] skip_spaces+0x30/0x30 [ 819.772242] RSP: 0018:ffff8804015cbc70 EFLAGS: 00010046 [ 819.772310] RAX: 0000000000000003 RBX: ffff88040cfd6d40 RCX: 0000000000000018 [ 819.772397] RDX: 0000000000020001 RSI: 0000000000000000 RDI: 0000000000000000 [ 819.772484] RBP: ffff8804015cbcc0 R08: 0000000000000000 R09: ffff8803f0768d40 [ 819.772570] R10: ffffea001033b800 R11: 0000000000000000 R12: ffffffff81c519c0 [ 819.772656] R13: 0000000000020001 R14: 0000000000000000 R15: 0000000000020001 [ 819.772744] FS: 00007ff98309b740(0000) GS:ffff88041f200000(0000) knlGS:0000000000000000 [ 819.772845] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 819.772917] CR2: 0000000000000000 CR3: 00000003f59dc000 CR4: 00000000001407f0 [ 819.773001] Stack: [ 819.773030] ffffffff81114003 ffff8804015cbcb0 0000000000000000 0000000000000046 [ 819.773146] ffff880409757a18 ffff8803f065a160 0000000000000000 0000000000020001 [ 819.773273] 0000000000000000 0000000000000000 ffff8804015cbce8 ffffffff8143e388 [ 819.773387] Call Trace: [ 819.773434] [] ? ftrace_raw_event_wakeup_source+0x43/0xe0 [ 819.773520] [] wakeup_source_report_event+0xb8/0xd0 [ 819.773595] [] __pm_stay_awake+0x2d/0x50 [ 819.773724] [] power_supply_changed+0x3c/0x90 [ 819.773795] [] power_supply_register+0x18c/0x250 [ 819.773869] [] sysfs_add_battery+0x61/0x7b [ 819.773935] [] battery_notify+0x37/0x3f [ 819.774001] [] notifier_call_chain+0x4c/0x70 [ 819.774071] [] __blocking_notifier_call_chain+0x4d/0x70 [ 819.774149] [] blocking_notifier_call_chain+0x16/0x20 [ 819.774227] [] pm_notifier_call_chain+0x1a/0x40 [ 819.774316] [] hibernate+0x66/0x1c0 [ 819.774407] [] state_store+0x71/0xa0 [ 819.774507] [] kobj_attr_store+0xf/0x20 [ 819.774613] [] sysfs_write_file+0x128/0x1c0 [ 819.774735] [] vfs_write+0xbd/0x1e0 [ 819.774841] [] SyS_write+0x49/0xa0 [ 819.774939] [] system_call_fastpath+0x16/0x1b [ 819.775055] Code: 89 f8 48 89 e5 f6 82 c0 a6 84 81 20 74 15 0f 1f 44 00 00 48 83 c0 01 0f b6 10 f6 82 c0 a6 84 81 20 75 f0 5d c3 66 0f 1f 44 00 00 <80> 3f 00 55 48 89 e5 74 15 48 89 f8 0f 1f 40 00 48 83 c0 01 80 [ 819.775760] RIP [] skip_spaces+0x30/0x30 [ 819.775881] RSP [ 819.775949] CR2: 0000000000000000 [ 819.794175] ---[ end trace c4ef25127039952e ]--- Signed-off-by: Shuah Khan Cc: stable@vger.kernel.org --- include/trace/events/power.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/include/trace/events/power.h b/include/trace/events/power.h index cda100d..5ba545a 100644 --- a/include/trace/events/power.h +++ b/include/trace/events/power.h @@ -110,12 +110,14 @@ DECLARE_EVENT_CLASS(wakeup_source, TP_ARGS(name, state), TP_STRUCT__entry( - __string( name, name ) + __string(name, name ? name : "(no name)") __field( u64, state ) ), TP_fast_assign( - __assign_str(name, name); + const char *tname = name ? name : "(no name)"; + + __assign_str(name, tname); __entry->state = state; ), -- 1.8.3.2