Revision 85bd839983778fcd0c1c043327b14a046e979b39 authored by Gu Zheng on 10 June 2015, 18:14:43 UTC, committed by Linus Torvalds on 10 June 2015, 23:43:43 UTC
Izumi found the following oops when hot re-adding a node:

    BUG: unable to handle kernel paging request at ffffc90008963690
    IP: __wake_up_bit+0x20/0x70
    Oops: 0000 [#1] SMP
    CPU: 68 PID: 1237 Comm: rs:main Q:Reg Not tainted 4.1.0-rc5 #80
    Hardware name: FUJITSU PRIMEQUEST2800E/SB, BIOS PRIMEQUEST 2000 Series BIOS Version 1.87 04/28/2015
    task: ffff880838df8000 ti: ffff880017b94000 task.ti: ffff880017b94000
    RIP: 0010:[<ffffffff810dff80>]  [<ffffffff810dff80>] __wake_up_bit+0x20/0x70
    RSP: 0018:ffff880017b97be8  EFLAGS: 00010246
    RAX: ffffc90008963690 RBX: 00000000003c0000 RCX: 000000000000a4c9
    RDX: 0000000000000000 RSI: ffffea101bffd500 RDI: ffffc90008963648
    RBP: ffff880017b97c08 R08: 0000000002000020 R09: 0000000000000000
    R10: 0000000000000000 R11: 0000000000000000 R12: ffff8a0797c73800
    R13: ffffea101bffd500 R14: 0000000000000001 R15: 00000000003c0000
    FS:  00007fcc7ffff700(0000) GS:ffff880874800000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: ffffc90008963690 CR3: 0000000836761000 CR4: 00000000001407e0
    Call Trace:
      unlock_page+0x6d/0x70
      generic_write_end+0x53/0xb0
      xfs_vm_write_end+0x29/0x80 [xfs]
      generic_perform_write+0x10a/0x1e0
      xfs_file_buffered_aio_write+0x14d/0x3e0 [xfs]
      xfs_file_write_iter+0x79/0x120 [xfs]
      __vfs_write+0xd4/0x110
      vfs_write+0xac/0x1c0
      SyS_write+0x58/0xd0
      system_call_fastpath+0x12/0x76
    Code: 5d c3 66 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 48 83 ec 20 65 48 8b 04 25 28 00 00 00 48 89 45 f8 31 c0 48 8d 47 48 <48> 39 47 48 48 c7 45 e8 00 00 00 00 48 c7 45 f0 00 00 00 00 48
    RIP  [<ffffffff810dff80>] __wake_up_bit+0x20/0x70
     RSP <ffff880017b97be8>
    CR2: ffffc90008963690

Reproduce method (re-add a node)::
  Hot-add nodeA --> remove nodeA --> hot-add nodeA (panic)

This seems an use-after-free problem, and the root cause is
zone->wait_table was not set to *NULL* after free it in
try_offline_node.

When hot re-add a node, we will reuse the pgdat of it, so does the zone
struct, and when add pages to the target zone, it will init the zone
first (including the wait_table) if the zone is not initialized.  The
judgement of zone initialized is based on zone->wait_table:

	static inline bool zone_is_initialized(struct zone *zone)
	{
		return !!zone->wait_table;
	}

so if we do not set the zone->wait_table to *NULL* after free it, the
memory hotplug routine will skip the init of new zone when hot re-add
the node, and the wait_table still points to the freed memory, then we
will access the invalid address when trying to wake up the waiting
people after the i/o operation with the page is done, such as mentioned
above.

Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Reported-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Reviewed by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent 5879ae5
Raw File
hid-roccat-pyra.h
#ifndef __HID_ROCCAT_PYRA_H
#define __HID_ROCCAT_PYRA_H

/*
 * Copyright (c) 2010 Stefan Achatz <erazor_de@users.sourceforge.net>
 */

/*
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 */

#include <linux/types.h>

enum {
	PYRA_SIZE_CONTROL = 0x03,
	PYRA_SIZE_INFO = 0x06,
	PYRA_SIZE_PROFILE_SETTINGS = 0x0d,
	PYRA_SIZE_PROFILE_BUTTONS = 0x13,
	PYRA_SIZE_SETTINGS = 0x03,
};

enum pyra_control_requests {
	PYRA_CONTROL_REQUEST_PROFILE_SETTINGS = 0x10,
	PYRA_CONTROL_REQUEST_PROFILE_BUTTONS = 0x20
};

struct pyra_settings {
	uint8_t command; /* PYRA_COMMAND_SETTINGS */
	uint8_t size; /* always 3 */
	uint8_t startup_profile; /* Range 0-4! */
} __attribute__ ((__packed__));

struct pyra_profile_settings {
	uint8_t command; /* PYRA_COMMAND_PROFILE_SETTINGS */
	uint8_t size; /* always 0xd */
	uint8_t number; /* Range 0-4 */
	uint8_t xysync;
	uint8_t x_sensitivity; /* 0x1-0xa */
	uint8_t y_sensitivity;
	uint8_t x_cpi; /* unused */
	uint8_t y_cpi; /* this value is for x and y */
	uint8_t lightswitch; /* 0 = off, 1 = on */
	uint8_t light_effect;
	uint8_t handedness;
	uint16_t checksum; /* byte sum */
} __attribute__ ((__packed__));

struct pyra_info {
	uint8_t command; /* PYRA_COMMAND_INFO */
	uint8_t size; /* always 6 */
	uint8_t firmware_version;
	uint8_t unknown1; /* always 0 */
	uint8_t unknown2; /* always 1 */
	uint8_t unknown3; /* always 0 */
} __attribute__ ((__packed__));

enum pyra_commands {
	PYRA_COMMAND_CONTROL = 0x4,
	PYRA_COMMAND_SETTINGS = 0x5,
	PYRA_COMMAND_PROFILE_SETTINGS = 0x6,
	PYRA_COMMAND_PROFILE_BUTTONS = 0x7,
	PYRA_COMMAND_INFO = 0x9,
	PYRA_COMMAND_B = 0xb
};

enum pyra_mouse_report_numbers {
	PYRA_MOUSE_REPORT_NUMBER_HID = 1,
	PYRA_MOUSE_REPORT_NUMBER_AUDIO = 2,
	PYRA_MOUSE_REPORT_NUMBER_BUTTON = 3,
};

struct pyra_mouse_event_button {
	uint8_t report_number; /* always 3 */
	uint8_t unknown; /* always 0 */
	uint8_t type;
	uint8_t data1;
	uint8_t data2;
} __attribute__ ((__packed__));

struct pyra_mouse_event_audio {
	uint8_t report_number; /* always 2 */
	uint8_t type;
	uint8_t unused; /* always 0 */
} __attribute__ ((__packed__));

/* hid audio controls */
enum pyra_mouse_event_audio_types {
	PYRA_MOUSE_EVENT_AUDIO_TYPE_MUTE = 0xe2,
	PYRA_MOUSE_EVENT_AUDIO_TYPE_VOLUME_UP = 0xe9,
	PYRA_MOUSE_EVENT_AUDIO_TYPE_VOLUME_DOWN = 0xea,
};

enum pyra_mouse_event_button_types {
	/*
	 * Mouse sends tilt events on report_number 1 and 3
	 * Tilt events are sent repeatedly with 0.94s between first and second
	 * event and 0.22s on subsequent
	 */
	PYRA_MOUSE_EVENT_BUTTON_TYPE_TILT = 0x10,

	/*
	 * These are sent sequentially
	 * data1 contains new profile number in range 1-5
	 */
	PYRA_MOUSE_EVENT_BUTTON_TYPE_PROFILE_1 = 0x20,
	PYRA_MOUSE_EVENT_BUTTON_TYPE_PROFILE_2 = 0x30,

	/*
	 * data1 = button_number (rmp index)
	 * data2 = pressed/released
	 */
	PYRA_MOUSE_EVENT_BUTTON_TYPE_MACRO = 0x40,
	PYRA_MOUSE_EVENT_BUTTON_TYPE_SHORTCUT = 0x50,

	/*
	 * data1 = button_number (rmp index)
	 */
	PYRA_MOUSE_EVENT_BUTTON_TYPE_QUICKLAUNCH = 0x60,

	/* data1 = new cpi */
	PYRA_MOUSE_EVENT_BUTTON_TYPE_CPI = 0xb0,

	/* data1 and data2 = new sensitivity */
	PYRA_MOUSE_EVENT_BUTTON_TYPE_SENSITIVITY = 0xc0,

	PYRA_MOUSE_EVENT_BUTTON_TYPE_MULTIMEDIA = 0xf0,
};

enum {
	PYRA_MOUSE_EVENT_BUTTON_PRESS = 0,
	PYRA_MOUSE_EVENT_BUTTON_RELEASE = 1,
};

struct pyra_roccat_report {
	uint8_t type;
	uint8_t value;
	uint8_t key;
} __attribute__ ((__packed__));

struct pyra_device {
	int actual_profile;
	int actual_cpi;
	int roccat_claimed;
	int chrdev_minor;
	struct mutex pyra_lock;
	struct pyra_profile_settings profile_settings[5];
};

#endif
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