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-gyration.c
/*
 *  HID driver for some gyration "special" devices
 *
 *  Copyright (c) 1999 Andreas Gal
 *  Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz>
 *  Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc
 *  Copyright (c) 2008 Jiri Slaby
 *  Copyright (c) 2006-2008 Jiri Kosina
 */

/*
 * 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/device.h>
#include <linux/input.h>
#include <linux/hid.h>
#include <linux/module.h>

#include "hid-ids.h"

#define gy_map_key_clear(c)	hid_map_usage_clear(hi, usage, bit, max, \
					EV_KEY, (c))
static int gyration_input_mapping(struct hid_device *hdev, struct hid_input *hi,
		struct hid_field *field, struct hid_usage *usage,
		unsigned long **bit, int *max)
{
	if ((usage->hid & HID_USAGE_PAGE) != HID_UP_LOGIVENDOR)
		return 0;

	set_bit(EV_REP, hi->input->evbit);
	switch (usage->hid & HID_USAGE) {
	/* Reported on Gyration MCE Remote */
	case 0x00d: gy_map_key_clear(KEY_HOME);		break;
	case 0x024: gy_map_key_clear(KEY_DVD);		break;
	case 0x025: gy_map_key_clear(KEY_PVR);		break;
	case 0x046: gy_map_key_clear(KEY_MEDIA);	break;
	case 0x047: gy_map_key_clear(KEY_MP3);		break;
	case 0x048: gy_map_key_clear(KEY_MEDIA);	break;
	case 0x049: gy_map_key_clear(KEY_CAMERA);	break;
	case 0x04a: gy_map_key_clear(KEY_VIDEO);	break;
	case 0x05a: gy_map_key_clear(KEY_TEXT);		break;
	case 0x05b: gy_map_key_clear(KEY_RED);		break;
	case 0x05c: gy_map_key_clear(KEY_GREEN);	break;
	case 0x05d: gy_map_key_clear(KEY_YELLOW);	break;
	case 0x05e: gy_map_key_clear(KEY_BLUE);		break;

	default:
		return 0;
	}
	return 1;
}

static int gyration_event(struct hid_device *hdev, struct hid_field *field,
		struct hid_usage *usage, __s32 value)
{

	if (!(hdev->claimed & HID_CLAIMED_INPUT) || !field->hidinput)
		return 0;

	if ((usage->hid & HID_USAGE_PAGE) == HID_UP_GENDESK &&
			(usage->hid & 0xff) == 0x82) {
		struct input_dev *input = field->hidinput->input;
		input_event(input, usage->type, usage->code, 1);
		input_sync(input);
		input_event(input, usage->type, usage->code, 0);
		input_sync(input);
		return 1;
	}

	return 0;
}

static const struct hid_device_id gyration_devices[] = {
	{ HID_USB_DEVICE(USB_VENDOR_ID_GYRATION, USB_DEVICE_ID_GYRATION_REMOTE) },
	{ HID_USB_DEVICE(USB_VENDOR_ID_GYRATION, USB_DEVICE_ID_GYRATION_REMOTE_2) },
	{ HID_USB_DEVICE(USB_VENDOR_ID_GYRATION, USB_DEVICE_ID_GYRATION_REMOTE_3) },
	{ }
};
MODULE_DEVICE_TABLE(hid, gyration_devices);

static struct hid_driver gyration_driver = {
	.name = "gyration",
	.id_table = gyration_devices,
	.input_mapping = gyration_input_mapping,
	.event = gyration_event,
};
module_hid_driver(gyration_driver);

MODULE_LICENSE("GPL");
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