forked from mirrors/linux
277fe44dd8
It is unsafe to call list_for_each_entry in hidraw_report_event to traverse each hidraw_list node without a lock protection, the list could be modified if someone calls hidraw_release and list_del to remove itself from the list, this can cause hidraw_report_event to touch a deleted list struct and panic. To prevent this, introduce a spinlock in struct hidraw to protect list from concurrent access. Signed-off-by: Yonghua Zheng <younghua.zheng@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
59 lines
1.5 KiB
C
59 lines
1.5 KiB
C
/*
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* Copyright (c) 2007 Jiri Kosina
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*/
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/*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms and conditions of the GNU General Public License,
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* version 2, as published by the Free Software Foundation.
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*
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* You should have received a copy of the GNU General Public License along with
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* this program; if not, write to the Free Software Foundation, Inc.,
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* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
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*/
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#ifndef _HIDRAW_H
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#define _HIDRAW_H
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#include <uapi/linux/hidraw.h>
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struct hidraw {
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unsigned int minor;
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int exist;
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int open;
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wait_queue_head_t wait;
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struct hid_device *hid;
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struct device *dev;
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spinlock_t list_lock;
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struct list_head list;
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};
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struct hidraw_report {
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__u8 *value;
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int len;
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};
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struct hidraw_list {
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struct hidraw_report buffer[HIDRAW_BUFFER_SIZE];
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int head;
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int tail;
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struct fasync_struct *fasync;
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struct hidraw *hidraw;
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struct list_head node;
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struct mutex read_mutex;
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};
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#ifdef CONFIG_HIDRAW
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int hidraw_init(void);
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void hidraw_exit(void);
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int hidraw_report_event(struct hid_device *, u8 *, int);
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int hidraw_connect(struct hid_device *);
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void hidraw_disconnect(struct hid_device *);
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#else
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static inline int hidraw_init(void) { return 0; }
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static inline void hidraw_exit(void) { }
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static inline int hidraw_report_event(struct hid_device *hid, u8 *data, int len) { return 0; }
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static inline int hidraw_connect(struct hid_device *hid) { return -1; }
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static inline void hidraw_disconnect(struct hid_device *hid) { }
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#endif
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#endif
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