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  • /* auditsc.c -- System-call auditing support
    
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     * Handles all system-call specific auditing features.
     *
     * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina.
    
     * Copyright 2005 Hewlett-Packard Development Company, L.P.
    
     * Copyright (C) 2005, 2006 IBM Corporation
    
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     * All Rights Reserved.
     *
     * 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.
     *
     * This program is distributed in the hope that it will be useful,
     * but WITHOUT ANY WARRANTY; without even the implied warranty of
     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     * GNU General Public License for more details.
     *
     * You should have received a copy of the GNU General Public License
     * along with this program; if not, write to the Free Software
     * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
     *
     * Written by Rickard E. (Rik) Faith <faith@redhat.com>
     *
     * Many of the ideas implemented here are from Stephen C. Tweedie,
     * especially the idea of avoiding a copy by using getname.
     *
     * The method for actual interception of syscall entry and exit (not in
     * this file -- see entry.S) is based on a GPL'd patch written by
     * okir@suse.de and Copyright 2003 SuSE Linux AG.
     *
    
     * POSIX message queue support added by George Wilson <ltcgcw@us.ibm.com>,
     * 2006.
     *
    
     * The support of additional filter rules compares (>, <, >=, <=) was
     * added by Dustin Kirkland <dustin.kirkland@us.ibm.com>, 2005.
     *
    
     * Modified by Amy Griffis <amy.griffis@hp.com> to collect additional
     * filesystem information.
    
     *
     * Subject and object context labeling support added by <danjones@us.ibm.com>
     * and <dustin.kirkland@us.ibm.com> for LSPP certification compliance.
    
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     */
    
    #include <linux/init.h>
    #include <asm/types.h>
    
    #include <asm/atomic.h>
    
    #include <asm/types.h>
    #include <linux/fs.h>
    #include <linux/namei.h>
    
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    #include <linux/mm.h>
    #include <linux/module.h>
    
    #include <linux/mount.h>
    
    #include <linux/socket.h>
    
    #include <linux/mqueue.h>
    
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    #include <linux/audit.h>
    #include <linux/personality.h>
    #include <linux/time.h>
    
    #include <linux/netlink.h>
    
    #include <linux/compiler.h>
    
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    #include <asm/unistd.h>
    
    #include <linux/security.h>
    
    #include <linux/tty.h>
    
    #include <linux/selinux.h>
    
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    #include <linux/binfmts.h>
    
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    #include <linux/syscalls.h>
    
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    extern struct list_head audit_filter_list[];
    
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    /* No syscall auditing will take place unless audit_enabled != 0. */
    extern int audit_enabled;
    
    /* AUDIT_NAMES is the number of slots we reserve in the audit_context
     * for saving names from getname(). */
    #define AUDIT_NAMES    20
    
    /* AUDIT_NAMES_RESERVED is the number of slots we reserve in the
     * audit_context from being used for nameless inodes from
     * path_lookup. */
    #define AUDIT_NAMES_RESERVED 7
    
    
    /* Indicates that audit should log the full pathname. */
    #define AUDIT_NAME_FULL -1
    
    
    /* number of audit rules */
    int audit_n_rules;
    
    
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    /* When fs/namei.c:getname() is called, we store the pointer in name and
     * we don't let putname() free it (instead we free all of the saved
     * pointers at syscall exit time).
     *
     * Further, in fs/namei.c:path_lookup() we store the inode and device. */
    struct audit_names {
    	const char	*name;
    
    	int		name_len;	/* number of name's characters to log */
    	unsigned	name_put;	/* call __putname() for this name */
    
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    	unsigned long	ino;
    	dev_t		dev;
    	umode_t		mode;
    	uid_t		uid;
    	gid_t		gid;
    	dev_t		rdev;
    
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    	u32		osid;
    
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    };
    
    struct audit_aux_data {
    	struct audit_aux_data	*next;
    	int			type;
    };
    
    #define AUDIT_AUX_IPCPERM	0
    
    
    struct audit_aux_data_mq_open {
    	struct audit_aux_data	d;
    	int			oflag;
    	mode_t			mode;
    	struct mq_attr		attr;
    };
    
    struct audit_aux_data_mq_sendrecv {
    	struct audit_aux_data	d;
    	mqd_t			mqdes;
    	size_t			msg_len;
    	unsigned int		msg_prio;
    	struct timespec		abs_timeout;
    };
    
    struct audit_aux_data_mq_notify {
    	struct audit_aux_data	d;
    	mqd_t			mqdes;
    	struct sigevent 	notification;
    };
    
    struct audit_aux_data_mq_getsetattr {
    	struct audit_aux_data	d;
    	mqd_t			mqdes;
    	struct mq_attr 		mqstat;
    };
    
    
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    struct audit_aux_data_ipcctl {
    	struct audit_aux_data	d;
    	struct ipc_perm		p;
    	unsigned long		qbytes;
    	uid_t			uid;
    	gid_t			gid;
    	mode_t			mode;
    
    	u32			osid;
    
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    };
    
    
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    struct audit_aux_data_execve {
    	struct audit_aux_data	d;
    	int argc;
    	int envc;
    	char mem[0];
    };
    
    
    struct audit_aux_data_socketcall {
    	struct audit_aux_data	d;
    	int			nargs;
    	unsigned long		args[0];
    };
    
    struct audit_aux_data_sockaddr {
    	struct audit_aux_data	d;
    	int			len;
    	char			a[0];
    };
    
    
    struct audit_aux_data_path {
    	struct audit_aux_data	d;
    	struct dentry		*dentry;
    	struct vfsmount		*mnt;
    };
    
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    /* The per-task audit context. */
    struct audit_context {
    
    	int		    dummy;	/* must be the first element */
    
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    	int		    in_syscall;	/* 1 if task is in a syscall */
    	enum audit_state    state;
    	unsigned int	    serial;     /* serial number for record */
    	struct timespec	    ctime;      /* time of syscall entry */
    	uid_t		    loginuid;   /* login uid (identity) */
    	int		    major;      /* syscall number */
    	unsigned long	    argv[4];    /* syscall arguments */
    	int		    return_valid; /* return code is valid */
    
    	long		    return_code;/* syscall return code */
    
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    	int		    auditable;  /* 1 if record should be written */
    	int		    name_count;
    	struct audit_names  names[AUDIT_NAMES];
    
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    	char *		    filterkey;	/* key for rule that triggered record */
    
    	struct dentry *	    pwd;
    	struct vfsmount *   pwdmnt;
    
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    	struct audit_context *previous; /* For nested syscalls */
    	struct audit_aux_data *aux;
    
    				/* Save things to print about task_struct */
    
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    	pid_t		    pid, ppid;
    
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    	uid_t		    uid, euid, suid, fsuid;
    	gid_t		    gid, egid, sgid, fsgid;
    	unsigned long	    personality;
    
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    #if AUDIT_DEBUG
    	int		    put_count;
    	int		    ino_count;
    #endif
    };
    
    
    #define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE])
    static inline int open_arg(int flags, int mask)
    {
    	int n = ACC_MODE(flags);
    	if (flags & (O_TRUNC | O_CREAT))
    		n |= AUDIT_PERM_WRITE;
    	return n & mask;
    }
    
    static int audit_match_perm(struct audit_context *ctx, int mask)
    {
    	unsigned n = ctx->major;
    	switch (audit_classify_syscall(ctx->arch, n)) {
    	case 0:	/* native */
    		if ((mask & AUDIT_PERM_WRITE) &&
    		     audit_match_class(AUDIT_CLASS_WRITE, n))
    			return 1;
    		if ((mask & AUDIT_PERM_READ) &&
    		     audit_match_class(AUDIT_CLASS_READ, n))
    			return 1;
    		if ((mask & AUDIT_PERM_ATTR) &&
    		     audit_match_class(AUDIT_CLASS_CHATTR, n))
    			return 1;
    		return 0;
    	case 1: /* 32bit on biarch */
    		if ((mask & AUDIT_PERM_WRITE) &&
    		     audit_match_class(AUDIT_CLASS_WRITE_32, n))
    			return 1;
    		if ((mask & AUDIT_PERM_READ) &&
    		     audit_match_class(AUDIT_CLASS_READ_32, n))
    			return 1;
    		if ((mask & AUDIT_PERM_ATTR) &&
    		     audit_match_class(AUDIT_CLASS_CHATTR_32, n))
    			return 1;
    		return 0;
    	case 2: /* open */
    		return mask & ACC_MODE(ctx->argv[1]);
    	case 3: /* openat */
    		return mask & ACC_MODE(ctx->argv[2]);
    	case 4: /* socketcall */
    		return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
    	case 5: /* execve */
    		return mask & AUDIT_PERM_EXEC;
    	default:
    		return 0;
    	}
    }
    
    
    /* Determine if any context name data matches a rule's watch data */
    
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    /* Compare a task_struct with an audit_rule.  Return 1 on match, 0
     * otherwise. */
    static int audit_filter_rules(struct task_struct *tsk,
    
    			      struct audit_krule *rule,
    
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    			      struct audit_context *ctx,
    
    			      struct audit_names *name,
    
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    			      enum audit_state *state)
    {
    
    	int i, j, need_sid = 1;
    
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    	for (i = 0; i < rule->field_count; i++) {
    
    		struct audit_field *f = &rule->fields[i];
    
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    		int result = 0;
    
    
    		switch (f->type) {
    
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    		case AUDIT_PID:
    
    			result = audit_comparator(tsk->pid, f->op, f->val);
    
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    			break;
    
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    		case AUDIT_PPID:
    
    			if (ctx) {
    				if (!ctx->ppid)
    					ctx->ppid = sys_getppid();
    
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    				result = audit_comparator(ctx->ppid, f->op, f->val);
    
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    			break;
    
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    		case AUDIT_UID:
    
    			result = audit_comparator(tsk->uid, f->op, f->val);
    
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    			break;
    		case AUDIT_EUID:
    
    			result = audit_comparator(tsk->euid, f->op, f->val);
    
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    			break;
    		case AUDIT_SUID:
    
    			result = audit_comparator(tsk->suid, f->op, f->val);
    
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    			break;
    		case AUDIT_FSUID:
    
    			result = audit_comparator(tsk->fsuid, f->op, f->val);
    
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    			break;
    		case AUDIT_GID:
    
    			result = audit_comparator(tsk->gid, f->op, f->val);
    
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    			break;
    		case AUDIT_EGID:
    
    			result = audit_comparator(tsk->egid, f->op, f->val);
    
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    			break;
    		case AUDIT_SGID:
    
    			result = audit_comparator(tsk->sgid, f->op, f->val);
    
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    			break;
    		case AUDIT_FSGID:
    
    			result = audit_comparator(tsk->fsgid, f->op, f->val);
    
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    			break;
    		case AUDIT_PERS:
    
    			result = audit_comparator(tsk->personality, f->op, f->val);
    
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    			break;
    
    				result = audit_comparator(ctx->arch, f->op, f->val);
    
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    		case AUDIT_EXIT:
    			if (ctx && ctx->return_valid)
    
    				result = audit_comparator(ctx->return_code, f->op, f->val);
    
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    			break;
    		case AUDIT_SUCCESS:
    
    			if (ctx && ctx->return_valid) {
    
    				if (f->val)
    					result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS);
    
    					result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE);
    
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    			break;
    		case AUDIT_DEVMAJOR:
    
    			if (name)
    				result = audit_comparator(MAJOR(name->dev),
    							  f->op, f->val);
    			else if (ctx) {
    
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    				for (j = 0; j < ctx->name_count; j++) {
    
    					if (audit_comparator(MAJOR(ctx->names[j].dev),	f->op, f->val)) {
    
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    						++result;
    						break;
    					}
    				}
    			}
    			break;
    		case AUDIT_DEVMINOR:
    
    			if (name)
    				result = audit_comparator(MINOR(name->dev),
    							  f->op, f->val);
    			else if (ctx) {
    
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    				for (j = 0; j < ctx->name_count; j++) {
    
    					if (audit_comparator(MINOR(ctx->names[j].dev), f->op, f->val)) {
    
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    						++result;
    						break;
    					}
    				}
    			}
    			break;
    		case AUDIT_INODE:
    
    			if (name)
    
    				result = (name->ino == f->val);
    
    			else if (ctx) {
    
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    				for (j = 0; j < ctx->name_count; j++) {
    
    					if (audit_comparator(ctx->names[j].ino, f->op, f->val)) {
    
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    						++result;
    						break;
    					}
    				}
    			}
    			break;
    
    		case AUDIT_WATCH:
    			if (name && rule->watch->ino != (unsigned long)-1)
    				result = (name->dev == rule->watch->dev &&
    
    					  name->ino == rule->watch->ino);
    
    			break;
    
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    		case AUDIT_LOGINUID:
    			result = 0;
    			if (ctx)
    
    				result = audit_comparator(ctx->loginuid, f->op, f->val);
    
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    			break;
    
    		case AUDIT_SUBJ_USER:
    		case AUDIT_SUBJ_ROLE:
    		case AUDIT_SUBJ_TYPE:
    		case AUDIT_SUBJ_SEN:
    		case AUDIT_SUBJ_CLR:
    
    			/* NOTE: this may return negative values indicating
    			   a temporary error.  We simply treat this as a
    			   match for now to avoid losing information that
    			   may be wanted.   An error message will also be
    			   logged upon error */
    
    			if (f->se_rule) {
    				if (need_sid) {
    
    					selinux_get_task_sid(tsk, &sid);
    
    					need_sid = 0;
    				}
    
    				result = selinux_audit_rule_match(sid, f->type,
    				                                  f->op,
    				                                  f->se_rule,
    				                                  ctx);
    
    		case AUDIT_OBJ_USER:
    		case AUDIT_OBJ_ROLE:
    		case AUDIT_OBJ_TYPE:
    		case AUDIT_OBJ_LEV_LOW:
    		case AUDIT_OBJ_LEV_HIGH:
    			/* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR
    			   also applies here */
    			if (f->se_rule) {
    				/* Find files that match */
    				if (name) {
    					result = selinux_audit_rule_match(
    					           name->osid, f->type, f->op,
    					           f->se_rule, ctx);
    				} else if (ctx) {
    					for (j = 0; j < ctx->name_count; j++) {
    						if (selinux_audit_rule_match(
    						      ctx->names[j].osid,
    						      f->type, f->op,
    						      f->se_rule, ctx)) {
    							++result;
    							break;
    						}
    					}
    				}
    				/* Find ipc objects that match */
    				if (ctx) {
    					struct audit_aux_data *aux;
    					for (aux = ctx->aux; aux;
    					     aux = aux->next) {
    						if (aux->type == AUDIT_IPC) {
    							struct audit_aux_data_ipcctl *axi = (void *)aux;
    							if (selinux_audit_rule_match(axi->osid, f->type, f->op, f->se_rule, ctx)) {
    								++result;
    								break;
    							}
    						}
    					}
    				}
    			}
    			break;
    
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    		case AUDIT_ARG0:
    		case AUDIT_ARG1:
    		case AUDIT_ARG2:
    		case AUDIT_ARG3:
    			if (ctx)
    
    				result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val);
    
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    			break;
    
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    		case AUDIT_FILTERKEY:
    			/* ignore this field for filtering */
    			result = 1;
    			break;
    
    		case AUDIT_PERM:
    			result = audit_match_perm(ctx, f->val);
    			break;
    
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    		}
    
    		if (!result)
    			return 0;
    	}
    
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    	if (rule->filterkey)
    		ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC);
    
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    	switch (rule->action) {
    	case AUDIT_NEVER:    *state = AUDIT_DISABLED;	    break;
    	case AUDIT_ALWAYS:   *state = AUDIT_RECORD_CONTEXT; break;
    	}
    	return 1;
    }
    
    /* At process creation time, we can determine if system-call auditing is
     * completely disabled for this task.  Since we only have the task
     * structure at this point, we can only check uid and gid.
     */
    static enum audit_state audit_filter_task(struct task_struct *tsk)
    {
    	struct audit_entry *e;
    	enum audit_state   state;
    
    	rcu_read_lock();
    
    	list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
    
    		if (audit_filter_rules(tsk, &e->rule, NULL, NULL, &state)) {
    
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    			rcu_read_unlock();
    			return state;
    		}
    	}
    	rcu_read_unlock();
    	return AUDIT_BUILD_CONTEXT;
    }
    
    /* At syscall entry and exit time, this filter is called if the
     * audit_state is not low enough that auditing cannot take place, but is
    
     * also not high enough that we already know we have to write an audit
    
     * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
    
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     */
    static enum audit_state audit_filter_syscall(struct task_struct *tsk,
    					     struct audit_context *ctx,
    					     struct list_head *list)
    {
    	struct audit_entry *e;
    
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    	if (audit_pid && tsk->tgid == audit_pid)
    
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    	rcu_read_lock();
    
    		int word = AUDIT_WORD(ctx->major);
    		int bit  = AUDIT_BIT(ctx->major);
    
    		list_for_each_entry_rcu(e, list, list) {
    
    			if ((e->rule.mask[word] & bit) == bit &&
    			    audit_filter_rules(tsk, &e->rule, ctx, NULL,
    					       &state)) {
    				rcu_read_unlock();
    				return state;
    			}
    		}
    	}
    	rcu_read_unlock();
    	return AUDIT_BUILD_CONTEXT;
    }
    
    /* At syscall exit time, this filter is called if any audit_names[] have been
     * collected during syscall processing.  We only check rules in sublists at hash
     * buckets applicable to the inode numbers in audit_names[].
     * Regarding audit_state, same rules apply as for audit_filter_syscall().
     */
    enum audit_state audit_filter_inodes(struct task_struct *tsk,
    				     struct audit_context *ctx)
    {
    	int i;
    	struct audit_entry *e;
    	enum audit_state state;
    
    	if (audit_pid && tsk->tgid == audit_pid)
    		return AUDIT_DISABLED;
    
    	rcu_read_lock();
    	for (i = 0; i < ctx->name_count; i++) {
    		int word = AUDIT_WORD(ctx->major);
    		int bit  = AUDIT_BIT(ctx->major);
    		struct audit_names *n = &ctx->names[i];
    		int h = audit_hash_ino((u32)n->ino);
    		struct list_head *list = &audit_inode_hash[h];
    
    		if (list_empty(list))
    			continue;
    
    		list_for_each_entry_rcu(e, list, list) {
    			if ((e->rule.mask[word] & bit) == bit &&
    			    audit_filter_rules(tsk, &e->rule, ctx, n, &state)) {
    
    				rcu_read_unlock();
    				return state;
    			}
    
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    	return AUDIT_BUILD_CONTEXT;
    
    void audit_set_auditable(struct audit_context *ctx)
    {
    	ctx->auditable = 1;
    }
    
    
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    static inline struct audit_context *audit_get_context(struct task_struct *tsk,
    						      int return_valid,
    						      int return_code)
    {
    	struct audit_context *context = tsk->audit_context;
    
    	if (likely(!context))
    		return NULL;
    	context->return_valid = return_valid;
    	context->return_code  = return_code;
    
    
    	if (context->in_syscall && !context->dummy && !context->auditable) {
    
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    		enum audit_state state;
    
    		state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]);
    
    		if (state == AUDIT_RECORD_CONTEXT) {
    			context->auditable = 1;
    			goto get_context;
    		}
    
    		state = audit_filter_inodes(tsk, context);
    
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    		if (state == AUDIT_RECORD_CONTEXT)
    			context->auditable = 1;
    
    get_context:
    
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    	tsk->audit_context = NULL;
    	return context;
    }
    
    static inline void audit_free_names(struct audit_context *context)
    {
    	int i;
    
    #if AUDIT_DEBUG == 2
    	if (context->auditable
    	    ||context->put_count + context->ino_count != context->name_count) {
    
    		printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d"
    
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    		       " name_count=%d put_count=%d"
    		       " ino_count=%d [NOT freeing]\n",
    
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    		       context->serial, context->major, context->in_syscall,
    		       context->name_count, context->put_count,
    		       context->ino_count);
    
    		for (i = 0; i < context->name_count; i++) {
    
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    			printk(KERN_ERR "names[%d] = %p = %s\n", i,
    			       context->names[i].name,
    
    			       context->names[i].name ?: "(null)");
    
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    		dump_stack();
    		return;
    	}
    #endif
    #if AUDIT_DEBUG
    	context->put_count  = 0;
    	context->ino_count  = 0;
    #endif
    
    
    	for (i = 0; i < context->name_count; i++) {
    
    		if (context->names[i].name && context->names[i].name_put)
    
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    			__putname(context->names[i].name);
    
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    	context->name_count = 0;
    
    	if (context->pwd)
    		dput(context->pwd);
    	if (context->pwdmnt)
    		mntput(context->pwdmnt);
    	context->pwd = NULL;
    	context->pwdmnt = NULL;
    
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    }
    
    static inline void audit_free_aux(struct audit_context *context)
    {
    	struct audit_aux_data *aux;
    
    	while ((aux = context->aux)) {
    
    		if (aux->type == AUDIT_AVC_PATH) {
    			struct audit_aux_data_path *axi = (void *)aux;
    			dput(axi->dentry);
    			mntput(axi->mnt);
    		}
    
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    		context->aux = aux->next;
    		kfree(aux);
    	}
    }
    
    static inline void audit_zero_context(struct audit_context *context,
    				      enum audit_state state)
    {
    	uid_t loginuid = context->loginuid;
    
    	memset(context, 0, sizeof(*context));
    	context->state      = state;
    	context->loginuid   = loginuid;
    }
    
    static inline struct audit_context *audit_alloc_context(enum audit_state state)
    {
    	struct audit_context *context;
    
    	if (!(context = kmalloc(sizeof(*context), GFP_KERNEL)))
    		return NULL;
    	audit_zero_context(context, state);
    	return context;
    }
    
    
    /**
     * audit_alloc - allocate an audit context block for a task
     * @tsk: task
     *
     * Filter on the task information and allocate a per-task audit context
    
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     * if necessary.  Doing so turns on system call auditing for the
     * specified task.  This is called from copy_process, so no lock is
    
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    int audit_alloc(struct task_struct *tsk)
    {
    	struct audit_context *context;
    	enum audit_state     state;
    
    	if (likely(!audit_enabled))
    		return 0; /* Return if not auditing. */
    
    	state = audit_filter_task(tsk);
    	if (likely(state == AUDIT_DISABLED))
    		return 0;
    
    	if (!(context = audit_alloc_context(state))) {
    		audit_log_lost("out of memory in audit_alloc");
    		return -ENOMEM;
    	}
    
    				/* Preserve login uid */
    	context->loginuid = -1;
    	if (current->audit_context)
    		context->loginuid = current->audit_context->loginuid;
    
    	tsk->audit_context  = context;
    	set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
    	return 0;
    }
    
    static inline void audit_free_context(struct audit_context *context)
    {
    	struct audit_context *previous;
    	int		     count = 0;
    
    	do {
    		previous = context->previous;
    		if (previous || (count &&  count < 10)) {
    			++count;
    			printk(KERN_ERR "audit(:%d): major=%d name_count=%d:"
    			       " freeing multiple contexts (%d)\n",
    			       context->serial, context->major,
    			       context->name_count, count);
    		}
    		audit_free_names(context);
    		audit_free_aux(context);
    
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    		kfree(context->filterkey);
    
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    		kfree(context);
    		context  = previous;
    	} while (context);
    	if (count >= 10)
    		printk(KERN_ERR "audit: freed %d contexts\n", count);
    }
    
    
    static void audit_log_task_context(struct audit_buffer *ab)
    
    {
    	char *ctx = NULL;
    	ssize_t len = 0;
    
    	len = security_getprocattr(current, "current", NULL, 0);
    	if (len < 0) {
    		if (len != -EINVAL)
    			goto error_path;
    		return;
    	}
    
    
    	ctx = kmalloc(len, GFP_KERNEL);
    
    		goto error_path;
    
    	len = security_getprocattr(current, "current", ctx, len);
    	if (len < 0 )
    		goto error_path;
    
    	audit_log_format(ab, " subj=%s", ctx);
    
    	audit_panic("error in audit_log_task_context");
    
    static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
    
    	char name[sizeof(tsk->comm)];
    	struct mm_struct *mm = tsk->mm;
    
    	struct vm_area_struct *vma;
    
    
    	/* tsk == current */
    
    
    	get_task_comm(name, tsk);
    
    	audit_log_format(ab, " comm=");
    	audit_log_untrustedstring(ab, name);
    
    	if (mm) {
    		down_read(&mm->mmap_sem);
    		vma = mm->mmap;
    		while (vma) {
    			if ((vma->vm_flags & VM_EXECUTABLE) &&
    			    vma->vm_file) {
    				audit_log_d_path(ab, "exe=",
    						 vma->vm_file->f_dentry,
    						 vma->vm_file->f_vfsmnt);
    				break;
    			}
    			vma = vma->vm_next;
    
    		up_read(&mm->mmap_sem);
    
    	audit_log_task_context(ab);
    
    static void audit_log_exit(struct audit_context *context, struct task_struct *tsk)
    
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    {
    
    	int i, call_panic = 0;
    
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    	struct audit_buffer *ab;
    
    	struct audit_aux_data *aux;
    
    	const char *tty;
    
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    	/* tsk == current */
    
    	context->pid = tsk->pid;
    
    	if (!context->ppid)
    		context->ppid = sys_getppid();
    
    	context->uid = tsk->uid;
    	context->gid = tsk->gid;
    	context->euid = tsk->euid;
    	context->suid = tsk->suid;
    	context->fsuid = tsk->fsuid;
    	context->egid = tsk->egid;
    	context->sgid = tsk->sgid;
    	context->fsgid = tsk->fsgid;
    	context->personality = tsk->personality;
    
    
    	ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
    
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    	if (!ab)
    		return;		/* audit_panic has been called */
    
    	audit_log_format(ab, "arch=%x syscall=%d",
    			 context->arch, context->major);
    
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    	if (context->personality != PER_LINUX)
    		audit_log_format(ab, " per=%lx", context->personality);
    	if (context->return_valid)
    
    		audit_log_format(ab, " success=%s exit=%ld", 
    				 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
    				 context->return_code);
    
    
    	mutex_lock(&tty_mutex);
    
    	if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name)
    		tty = tsk->signal->tty->name;
    
    	else
    		tty = "(none)";
    
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    	audit_log_format(ab,
    		  " a0=%lx a1=%lx a2=%lx a3=%lx items=%d"
    
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    		  " ppid=%d pid=%d auid=%u uid=%u gid=%u"
    
    		  " egid=%u sgid=%u fsgid=%u tty=%s",
    
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    		  context->argv[0],
    		  context->argv[1],
    		  context->argv[2],
    		  context->argv[3],
    		  context->name_count,
    
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    		  context->ppid,
    
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    		  context->pid,
    		  context->loginuid,
    		  context->uid,
    		  context->gid,
    		  context->euid, context->suid, context->fsuid,
    
    		  context->egid, context->sgid, context->fsgid, tty);
    
    
    	mutex_unlock(&tty_mutex);
    
    
    	audit_log_task_info(ab, tsk);
    
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    	if (context->filterkey) {
    		audit_log_format(ab, " key=");
    		audit_log_untrustedstring(ab, context->filterkey);
    	} else
    		audit_log_format(ab, " key=(null)");
    
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    	audit_log_end(ab);
    
    
    	for (aux = context->aux; aux; aux = aux->next) {
    
    		ab = audit_log_start(context, GFP_KERNEL, aux->type);
    
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    		if (!ab)
    			continue; /* audit_panic has been called */
    
    		switch (aux->type) {
    
    		case AUDIT_MQ_OPEN: {
    			struct audit_aux_data_mq_open *axi = (void *)aux;
    			audit_log_format(ab,
    				"oflag=0x%x mode=%#o mq_flags=0x%lx mq_maxmsg=%ld "
    				"mq_msgsize=%ld mq_curmsgs=%ld",
    				axi->oflag, axi->mode, axi->attr.mq_flags,
    				axi->attr.mq_maxmsg, axi->attr.mq_msgsize,
    				axi->attr.mq_curmsgs);
    			break; }
    
    		case AUDIT_MQ_SENDRECV: {
    			struct audit_aux_data_mq_sendrecv *axi = (void *)aux;
    			audit_log_format(ab,
    				"mqdes=%d msg_len=%zd msg_prio=%u "
    				"abs_timeout_sec=%ld abs_timeout_nsec=%ld",
    				axi->mqdes, axi->msg_len, axi->msg_prio,
    				axi->abs_timeout.tv_sec, axi->abs_timeout.tv_nsec);
    			break; }
    
    		case AUDIT_MQ_NOTIFY: {
    			struct audit_aux_data_mq_notify *axi = (void *)aux;
    			audit_log_format(ab,
    				"mqdes=%d sigev_signo=%d",
    				axi->mqdes,
    				axi->notification.sigev_signo);
    			break; }
    
    		case AUDIT_MQ_GETSETATTR: {
    			struct audit_aux_data_mq_getsetattr *axi = (void *)aux;
    			audit_log_format(ab,
    				"mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld "
    				"mq_curmsgs=%ld ",
    				axi->mqdes,
    				axi->mqstat.mq_flags, axi->mqstat.mq_maxmsg,
    				axi->mqstat.mq_msgsize, axi->mqstat.mq_curmsgs);
    			break; }
    
    
    		case AUDIT_IPC: {
    
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    			struct audit_aux_data_ipcctl *axi = (void *)aux;
    			audit_log_format(ab, 
    
    				 "ouid=%u ogid=%u mode=%x",
    				 axi->uid, axi->gid, axi->mode);
    
    			if (axi->osid != 0) {
    				char *ctx = NULL;
    				u32 len;
    
    				if (selinux_sid_to_string(
    
    						axi->osid, &ctx, &len)) {
    
    					audit_log_format(ab, " osid=%u",
    
    							axi->osid);
    					call_panic = 1;
    				} else
    					audit_log_format(ab, " obj=%s", ctx);
    				kfree(ctx);
    			}
    
    		case AUDIT_IPC_SET_PERM: {
    			struct audit_aux_data_ipcctl *axi = (void *)aux;
    			audit_log_format(ab,
    
    				"qbytes=%lx ouid=%u ogid=%u mode=%x",
    
    				axi->qbytes, axi->uid, axi->gid, axi->mode);
    			break; }
    
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    		case AUDIT_EXECVE: {
    			struct audit_aux_data_execve *axi = (void *)aux;
    			int i;
    			const char *p;
    			for (i = 0, p = axi->mem; i < axi->argc; i++) {
    				audit_log_format(ab, "a%d=", i);
    				p = audit_log_untrustedstring(ab, p);
    				audit_log_format(ab, "\n");
    			}
    			break; }
    
    		case AUDIT_SOCKETCALL: {
    			int i;
    			struct audit_aux_data_socketcall *axs = (void *)aux;
    			audit_log_format(ab, "nargs=%d", axs->nargs);
    			for (i=0; i<axs->nargs; i++)
    				audit_log_format(ab, " a%d=%lx", i, axs->args[i]);
    			break; }
    
    		case AUDIT_SOCKADDR: {
    			struct audit_aux_data_sockaddr *axs = (void *)aux;
    
    			audit_log_format(ab, "saddr=");
    			audit_log_hex(ab, axs->a, axs->len);
    			break; }
    
    
    		case AUDIT_AVC_PATH: {
    			struct audit_aux_data_path *axi = (void *)aux;
    			audit_log_d_path(ab, "path=", axi->dentry, axi->mnt);
    			break; }
    
    
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    		}
    		audit_log_end(ab);
    	}
    
    
    	if (context->pwd && context->pwdmnt) {
    
    		ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
    
    		if (ab) {
    			audit_log_d_path(ab, "cwd=", context->pwd, context->pwdmnt);
    			audit_log_end(ab);
    		}
    	}
    
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    	for (i = 0; i < context->name_count; i++) {
    
    		struct audit_names *n = &context->names[i];
    
    		ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);
    
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    		if (!ab)
    			continue; /* audit_panic has been called */
    
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    		audit_log_format(ab, "item=%d", i);
    
    		if (n->name) {
    			switch(n->name_len) {
    			case AUDIT_NAME_FULL:
    				/* log the full path */
    				audit_log_format(ab, " name=");
    				audit_log_untrustedstring(ab, n->name);
    				break;
    			case 0:
    				/* name was specified as a relative path and the
    				 * directory component is the cwd */
    				audit_log_d_path(ab, " name=", context->pwd,
    						 context->pwdmnt);
    				break;
    			default:
    				/* log the name's directory component */
    				audit_log_format(ab, " name=");
    				audit_log_n_untrustedstring(ab, n->name_len,
    							    n->name);
    			}
    		} else
    			audit_log_format(ab, " name=(null)");