/* auditsc.c -- System-call auditing support

   * 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

   * 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.

   */
  
  #include <linux/init.h>

  #include <asm/types.h>

  #include <linux/atomic.h>

  #include <linux/fs.h>
  #include <linux/namei.h>

  #include <linux/mm.h>

  #include <linux/export.h>

  #include <linux/slab.h>

  #include <linux/mount.h>

  #include <linux/socket.h>

  #include <linux/mqueue.h>

  #include <linux/audit.h>
  #include <linux/personality.h>
  #include <linux/time.h>

  #include <linux/netlink.h>

  #include <linux/compiler.h>

  #include <asm/unistd.h>

  #include <linux/security.h>

  #include <linux/list.h>

  #include <linux/tty.h>

  #include <linux/binfmts.h>

  #include <linux/highmem.h>

  #include <linux/syscalls.h>

  #include <linux/capability.h>

  #include <linux/fs_struct.h>

  #include "audit.h"

  /* AUDIT_NAMES is the number of slots we reserve in the audit_context
   * for saving names from getname(). */
  #define AUDIT_NAMES    20

  /* Indicates that audit should log the full pathname. */
  #define AUDIT_NAME_FULL -1

  /* no execve audit message should be longer than this (userspace limits) */
  #define MAX_EXECVE_AUDIT_LEN 7500

  /* number of audit rules */
  int audit_n_rules;

  /* determines whether we collect data for signals sent */
  int audit_signals;

  struct audit_cap_data {
  	kernel_cap_t		permitted;
  	kernel_cap_t		inheritable;
  	union {
  		unsigned int	fE;		/* effective bit of a file capability */
  		kernel_cap_t	effective;	/* effective set of a process */
  	};
  };

  /* 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 */

  	unsigned long	ino;
  	dev_t		dev;
  	umode_t		mode;
  	uid_t		uid;
  	gid_t		gid;
  	dev_t		rdev;

  	u32		osid;

  	struct audit_cap_data fcap;
  	unsigned int	fcap_ver;

  };
  
  struct audit_aux_data {
  	struct audit_aux_data	*next;
  	int			type;
  };
  
  #define AUDIT_AUX_IPCPERM	0

  /* Number of target pids per aux struct. */
  #define AUDIT_AUX_PIDS	16

  struct audit_aux_data_execve {
  	struct audit_aux_data	d;
  	int argc;
  	int envc;

  	struct mm_struct *mm;

  };

  struct audit_aux_data_pids {
  	struct audit_aux_data	d;
  	pid_t			target_pid[AUDIT_AUX_PIDS];

  	uid_t			target_auid[AUDIT_AUX_PIDS];
  	uid_t			target_uid[AUDIT_AUX_PIDS];

  	unsigned int		target_sessionid[AUDIT_AUX_PIDS];

  	u32			target_sid[AUDIT_AUX_PIDS];

  	char 			target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];

  	int			pid_count;
  };

  struct audit_aux_data_bprm_fcaps {
  	struct audit_aux_data	d;
  	struct audit_cap_data	fcap;
  	unsigned int		fcap_ver;
  	struct audit_cap_data	old_pcap;
  	struct audit_cap_data	new_pcap;
  };

  struct audit_aux_data_capset {
  	struct audit_aux_data	d;
  	pid_t			pid;
  	struct audit_cap_data	cap;
  };

  struct audit_tree_refs {
  	struct audit_tree_refs *next;
  	struct audit_chunk *c[31];
  };

  /* The per-task audit context. */
  struct audit_context {

  	int		    dummy;	/* must be the first element */

  	int		    in_syscall;	/* 1 if task is in a syscall */

  	enum audit_state    state, current_state;

  	unsigned int	    serial;     /* serial number for record */

  	int		    major;      /* syscall number */

  	struct timespec	    ctime;      /* time of syscall entry */

  	unsigned long	    argv[4];    /* syscall arguments */

  	long		    return_code;/* syscall return code */

  	u64		    prio;

  	int		    return_valid; /* return code is valid */

  	int		    name_count;
  	struct audit_names  names[AUDIT_NAMES];

  	char *		    filterkey;	/* key for rule that triggered record */

  	struct path	    pwd;

  	struct audit_context *previous; /* For nested syscalls */
  	struct audit_aux_data *aux;

  	struct audit_aux_data *aux_pids;

  	struct sockaddr_storage *sockaddr;
  	size_t sockaddr_len;

  				/* Save things to print about task_struct */

  	pid_t		    pid, ppid;

  	uid_t		    uid, euid, suid, fsuid;
  	gid_t		    gid, egid, sgid, fsgid;
  	unsigned long	    personality;

  	int		    arch;

  	pid_t		    target_pid;

  	uid_t		    target_auid;
  	uid_t		    target_uid;

  	unsigned int	    target_sessionid;

  	u32		    target_sid;

  	char		    target_comm[TASK_COMM_LEN];

  	struct audit_tree_refs *trees, *first_trees;

  	struct list_head killed_trees;

  	int tree_count;

  	int type;
  	union {
  		struct {
  			int nargs;
  			long args[6];
  		} socketcall;

  		struct {
  			uid_t			uid;
  			gid_t			gid;

  			umode_t			mode;

  			u32			osid;

  			int			has_perm;
  			uid_t			perm_uid;
  			gid_t			perm_gid;

  			umode_t			perm_mode;

  			unsigned long		qbytes;

  		} ipc;

  		struct {
  			mqd_t			mqdes;
  			struct mq_attr 		mqstat;
  		} mq_getsetattr;

  		struct {
  			mqd_t			mqdes;
  			int			sigev_signo;
  		} mq_notify;

  		struct {
  			mqd_t			mqdes;
  			size_t			msg_len;
  			unsigned int		msg_prio;
  			struct timespec		abs_timeout;
  		} mq_sendrecv;

  		struct {
  			int			oflag;

  			umode_t			mode;

  			struct mq_attr		attr;
  		} mq_open;

  		struct {
  			pid_t			pid;
  			struct audit_cap_data	cap;
  		} capset;

  		struct {
  			int			fd;
  			int			flags;
  		} mmap;

  	};

  	int fds[2];

  #if AUDIT_DEBUG
  	int		    put_count;
  	int		    ino_count;
  #endif
  };

  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;

  	if (unlikely(!ctx))
  		return 0;

  	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;
  	}
  }

  static int audit_match_filetype(struct audit_context *ctx, int which)
  {
  	unsigned index = which & ~S_IFMT;

  	umode_t mode = which & S_IFMT;

  
  	if (unlikely(!ctx))
  		return 0;

  	if (index >= ctx->name_count)
  		return 0;
  	if (ctx->names[index].ino == -1)
  		return 0;
  	if ((ctx->names[index].mode ^ mode) & S_IFMT)
  		return 0;
  	return 1;
  }

  /*
   * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *;
   * ->first_trees points to its beginning, ->trees - to the current end of data.
   * ->tree_count is the number of free entries in array pointed to by ->trees.
   * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL,
   * "empty" becomes (p, p, 31) afterwards.  We don't shrink the list (and seriously,
   * it's going to remain 1-element for almost any setup) until we free context itself.
   * References in it _are_ dropped - at the same time we free/drop aux stuff.
   */
  
  #ifdef CONFIG_AUDIT_TREE

  static void audit_set_auditable(struct audit_context *ctx)
  {
  	if (!ctx->prio) {
  		ctx->prio = 1;
  		ctx->current_state = AUDIT_RECORD_CONTEXT;
  	}
  }

  static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk)
  {
  	struct audit_tree_refs *p = ctx->trees;
  	int left = ctx->tree_count;
  	if (likely(left)) {
  		p->c[--left] = chunk;
  		ctx->tree_count = left;
  		return 1;
  	}
  	if (!p)
  		return 0;
  	p = p->next;
  	if (p) {
  		p->c[30] = chunk;
  		ctx->trees = p;
  		ctx->tree_count = 30;
  		return 1;
  	}
  	return 0;
  }
  
  static int grow_tree_refs(struct audit_context *ctx)
  {
  	struct audit_tree_refs *p = ctx->trees;
  	ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL);
  	if (!ctx->trees) {
  		ctx->trees = p;
  		return 0;
  	}
  	if (p)
  		p->next = ctx->trees;
  	else
  		ctx->first_trees = ctx->trees;
  	ctx->tree_count = 31;
  	return 1;
  }
  #endif
  
  static void unroll_tree_refs(struct audit_context *ctx,
  		      struct audit_tree_refs *p, int count)
  {
  #ifdef CONFIG_AUDIT_TREE
  	struct audit_tree_refs *q;
  	int n;
  	if (!p) {
  		/* we started with empty chain */
  		p = ctx->first_trees;
  		count = 31;
  		/* if the very first allocation has failed, nothing to do */
  		if (!p)
  			return;
  	}
  	n = count;
  	for (q = p; q != ctx->trees; q = q->next, n = 31) {
  		while (n--) {
  			audit_put_chunk(q->c[n]);
  			q->c[n] = NULL;
  		}
  	}
  	while (n-- > ctx->tree_count) {
  		audit_put_chunk(q->c[n]);
  		q->c[n] = NULL;
  	}
  	ctx->trees = p;
  	ctx->tree_count = count;
  #endif
  }
  
  static void free_tree_refs(struct audit_context *ctx)
  {
  	struct audit_tree_refs *p, *q;
  	for (p = ctx->first_trees; p; p = q) {
  		q = p->next;
  		kfree(p);
  	}
  }
  
  static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree)
  {
  #ifdef CONFIG_AUDIT_TREE
  	struct audit_tree_refs *p;
  	int n;
  	if (!tree)
  		return 0;
  	/* full ones */
  	for (p = ctx->first_trees; p != ctx->trees; p = p->next) {
  		for (n = 0; n < 31; n++)
  			if (audit_tree_match(p->c[n], tree))
  				return 1;
  	}
  	/* partial */
  	if (p) {
  		for (n = ctx->tree_count; n < 31; n++)
  			if (audit_tree_match(p->c[n], tree))
  				return 1;
  	}
  #endif
  	return 0;
  }

  /* Determine if any context name data matches a rule's watch data */

  /* Compare a task_struct with an audit_rule.  Return 1 on match, 0

   * otherwise.
   *
   * If task_creation is true, this is an explicit indication that we are
   * filtering a task rule at task creation time.  This and tsk == current are
   * the only situations where tsk->cred may be accessed without an rcu read lock.
   */

  static int audit_filter_rules(struct task_struct *tsk,

  			      struct audit_krule *rule,

  			      struct audit_context *ctx,

  			      struct audit_names *name,

  			      enum audit_state *state,
  			      bool task_creation)

  {

  	const struct cred *cred;

  	int i, j, need_sid = 1;

  	u32 sid;

  	cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation);

  	for (i = 0; i < rule->field_count; i++) {

  		struct audit_field *f = &rule->fields[i];

  		int result = 0;

  		switch (f->type) {

  		case AUDIT_PID:

  			result = audit_comparator(tsk->pid, f->op, f->val);

  			break;

  		case AUDIT_PPID:

  			if (ctx) {
  				if (!ctx->ppid)
  					ctx->ppid = sys_getppid();

  				result = audit_comparator(ctx->ppid, f->op, f->val);

  			}

  			break;

  		case AUDIT_UID:

  			result = audit_comparator(cred->uid, f->op, f->val);

  			break;
  		case AUDIT_EUID:

  			result = audit_comparator(cred->euid, f->op, f->val);

  			break;
  		case AUDIT_SUID:

  			result = audit_comparator(cred->suid, f->op, f->val);

  			break;
  		case AUDIT_FSUID:

  			result = audit_comparator(cred->fsuid, f->op, f->val);

  			break;
  		case AUDIT_GID:

  			result = audit_comparator(cred->gid, f->op, f->val);

  			break;
  		case AUDIT_EGID:

  			result = audit_comparator(cred->egid, f->op, f->val);

  			break;
  		case AUDIT_SGID:

  			result = audit_comparator(cred->sgid, f->op, f->val);

  			break;
  		case AUDIT_FSGID:

  			result = audit_comparator(cred->fsgid, f->op, f->val);

  			break;
  		case AUDIT_PERS:

  			result = audit_comparator(tsk->personality, f->op, f->val);

  			break;

  		case AUDIT_ARCH:

  			if (ctx)

  				result = audit_comparator(ctx->arch, f->op, f->val);

  			break;

  
  		case AUDIT_EXIT:
  			if (ctx && ctx->return_valid)

  				result = audit_comparator(ctx->return_code, f->op, f->val);

  			break;
  		case AUDIT_SUCCESS:

  			if (ctx && ctx->return_valid) {

  				if (f->val)
  					result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS);

  				else

  					result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE);

  			}

  			break;
  		case AUDIT_DEVMAJOR:

  			if (name)
  				result = audit_comparator(MAJOR(name->dev),
  							  f->op, f->val);
  			else if (ctx) {

  				for (j = 0; j < ctx->name_count; j++) {

  					if (audit_comparator(MAJOR(ctx->names[j].dev),	f->op, f->val)) {

  						++result;
  						break;
  					}
  				}
  			}
  			break;
  		case AUDIT_DEVMINOR:

  			if (name)
  				result = audit_comparator(MINOR(name->dev),
  							  f->op, f->val);
  			else if (ctx) {

  				for (j = 0; j < ctx->name_count; j++) {

  					if (audit_comparator(MINOR(ctx->names[j].dev), f->op, f->val)) {

  						++result;
  						break;
  					}
  				}
  			}
  			break;
  		case AUDIT_INODE:

  			if (name)

  				result = (name->ino == f->val);

  			else if (ctx) {

  				for (j = 0; j < ctx->name_count; j++) {

  					if (audit_comparator(ctx->names[j].ino, f->op, f->val)) {

  						++result;
  						break;
  					}
  				}
  			}
  			break;

  		case AUDIT_WATCH:

  			if (name)
  				result = audit_watch_compare(rule->watch, name->ino, name->dev);

  			break;

  		case AUDIT_DIR:
  			if (ctx)
  				result = match_tree_refs(ctx, rule->tree);
  			break;

  		case AUDIT_LOGINUID:
  			result = 0;
  			if (ctx)

  				result = audit_comparator(tsk->loginuid, f->op, f->val);

  			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->lsm_rule) {

  				if (need_sid) {

  					security_task_getsecid(tsk, &sid);

  					need_sid = 0;
  				}

  				result = security_audit_rule_match(sid, f->type,

  				                                  f->op,

  				                                  f->lsm_rule,

  				                                  ctx);

  			}

  			break;

  		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->lsm_rule) {

  				/* Find files that match */
  				if (name) {

  					result = security_audit_rule_match(

  					           name->osid, f->type, f->op,

  					           f->lsm_rule, ctx);

  				} else if (ctx) {
  					for (j = 0; j < ctx->name_count; j++) {

  						if (security_audit_rule_match(

  						      ctx->names[j].osid,
  						      f->type, f->op,

  						      f->lsm_rule, ctx)) {

  							++result;
  							break;
  						}
  					}
  				}
  				/* Find ipc objects that match */

  				if (!ctx || ctx->type != AUDIT_IPC)
  					break;
  				if (security_audit_rule_match(ctx->ipc.osid,
  							      f->type, f->op,
  							      f->lsm_rule, ctx))
  					++result;

  			}
  			break;

  		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);

  			break;

  		case AUDIT_FILTERKEY:
  			/* ignore this field for filtering */
  			result = 1;
  			break;

  		case AUDIT_PERM:
  			result = audit_match_perm(ctx, f->val);
  			break;

  		case AUDIT_FILETYPE:
  			result = audit_match_filetype(ctx, f->val);
  			break;

  		}

  		if (!result)

  			return 0;
  	}

  
  	if (ctx) {
  		if (rule->prio <= ctx->prio)
  			return 0;
  		if (rule->filterkey) {
  			kfree(ctx->filterkey);
  			ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC);
  		}
  		ctx->prio = rule->prio;
  	}

  	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, char **key)

  {
  	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, true)) {

  			if (state == AUDIT_RECORD_CONTEXT)
  				*key = kstrdup(e->rule.filterkey, GFP_ATOMIC);

  			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).

   */
  static enum audit_state audit_filter_syscall(struct task_struct *tsk,
  					     struct audit_context *ctx,
  					     struct list_head *list)
  {
  	struct audit_entry *e;

  	enum audit_state state;

  	if (audit_pid && tsk->tgid == audit_pid)

  		return AUDIT_DISABLED;

  	rcu_read_lock();

  	if (!list_empty(list)) {

  		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, false)) {

  				rcu_read_unlock();

  				ctx->current_state = state;

  				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().
   */

  void 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;

  
  	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, false)) {

  				rcu_read_unlock();

  				ctx->current_state = state;
  				return;

  			}

  		}
  	}
  	rcu_read_unlock();

  }

  static inline struct audit_context *audit_get_context(struct task_struct *tsk,
  						      int return_valid,

  						      long return_code)

  {
  	struct audit_context *context = tsk->audit_context;
  
  	if (likely(!context))
  		return NULL;
  	context->return_valid = return_valid;

  
  	/*
  	 * we need to fix up the return code in the audit logs if the actual
  	 * return codes are later going to be fixed up by the arch specific
  	 * signal handlers
  	 *
  	 * This is actually a test for:
  	 * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) ||
  	 * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK)
  	 *
  	 * but is faster than a bunch of ||
  	 */
  	if (unlikely(return_code <= -ERESTARTSYS) &&
  	    (return_code >= -ERESTART_RESTARTBLOCK) &&
  	    (return_code != -ENOIOCTLCMD))
  		context->return_code = -EINTR;
  	else
  		context->return_code  = return_code;

  	if (context->in_syscall && !context->dummy) {
  		audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]);
  		audit_filter_inodes(tsk, context);

  	}

  	tsk->audit_context = NULL;
  	return context;
  }
  
  static inline void audit_free_names(struct audit_context *context)
  {
  	int i;
  
  #if AUDIT_DEBUG == 2

  	if (context->put_count + context->ino_count != context->name_count) {

  		printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d"

  		       " name_count=%d put_count=%d"
  		       " ino_count=%d [NOT freeing]
  ",

  		       __FILE__, __LINE__,

  		       context->serial, context->major, context->in_syscall,
  		       context->name_count, context->put_count,
  		       context->ino_count);

  		for (i = 0; i < context->name_count; i++) {

  			printk(KERN_ERR "names[%d] = %p = %s
  ", i,
  			       context->names[i].name,

  			       context->names[i].name ?: "(null)");

  		}

  		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)

  			__putname(context->names[i].name);

  	}

  	context->name_count = 0;

  	path_put(&context->pwd);
  	context->pwd.dentry = NULL;
  	context->pwd.mnt = NULL;

  }
  
  static inline void audit_free_aux(struct audit_context *context)
  {
  	struct audit_aux_data *aux;
  
  	while ((aux = context->aux)) {
  		context->aux = aux->next;
  		kfree(aux);
  	}

  	while ((aux = context->aux_pids)) {
  		context->aux_pids = aux->next;
  		kfree(aux);
  	}

  }
  
  static inline void audit_zero_context(struct audit_context *context,
  				      enum audit_state state)
  {

  	memset(context, 0, sizeof(*context));
  	context->state      = state;

  	context->prio = state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;

  }
  
  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);

  	INIT_LIST_HEAD(&context->killed_trees);

  	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

   * if necessary.  Doing so turns on system call auditing for the
   * specified task.  This is called from copy_process, so no lock is

   * needed.
   */

  int audit_alloc(struct task_struct *tsk)
  {
  	struct audit_context *context;
  	enum audit_state     state;

  	char *key = NULL;

  	if (likely(!audit_ever_enabled))

  		return 0; /* Return if not auditing. */

  	state = audit_filter_task(tsk, &key);

  	if (likely(state == AUDIT_DISABLED))
  		return 0;
  
  	if (!(context = audit_alloc_context(state))) {

  		kfree(key);

  		audit_log_lost("out of memory in audit_alloc");
  		return -ENOMEM;
  	}

  	context->filterkey = key;

  	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)
  ",
  			       context->serial, context->major,
  			       context->name_count, count);
  		}
  		audit_free_names(context);

  		unroll_tree_refs(context, NULL, 0);
  		free_tree_refs(context);

  		audit_free_aux(context);

  		kfree(context->filterkey);

  		kfree(context->sockaddr);

  		kfree(context);
  		context  = previous;
  	} while (context);
  	if (count >= 10)
  		printk(KERN_ERR "audit: freed %d contexts
  ", count);
  }

  void audit_log_task_context(struct audit_buffer *ab)

  {
  	char *ctx = NULL;

  	unsigned len;
  	int error;
  	u32 sid;

  	security_task_getsecid(current, &sid);

  	if (!sid)
  		return;

  	error = security_secid_to_secctx(sid, &ctx, &len);

  	if (error) {
  		if (error != -EINVAL)

  			goto error_path;
  		return;
  	}

  	audit_log_format(ab, " subj=%s", ctx);

  	security_release_secctx(ctx, len);

  	return;

  
  error_path:

  	audit_panic("error in audit_log_task_context");

  	return;
  }

  EXPORT_SYMBOL(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_path);

  				break;
  			}
  			vma = vma->vm_next;

  		}

  		up_read(&mm->mmap_sem);

  	}

  	audit_log_task_context(ab);

  }

  static int audit_log_pid_context(struct audit_context *context, pid_t pid,

  				 uid_t auid, uid_t uid, unsigned int sessionid,
  				 u32 sid, char *comm)

  {
  	struct audit_buffer *ab;

  	char *ctx = NULL;

  	u32 len;
  	int rc = 0;
  
  	ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
  	if (!ab)

  		return rc;

  	audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, auid,
  			 uid, sessionid);

  	if (security_secid_to_secctx(sid, &ctx, &len)) {

  		audit_log_format(ab, " obj=(none)");

  		rc = 1;

  	} else {
  		audit_log_format(ab, " obj=%s", ctx);
  		security_release_secctx(ctx, len);
  	}

  	audit_log_format(ab, " ocomm=");
  	audit_log_untrustedstring(ab, comm);

  	audit_log_end(ab);

  
  	return rc;
  }

  /*
   * to_send and len_sent accounting are very loose estimates.  We aren't
   * really worried about a hard cap to MAX_EXECVE_AUDIT_LEN so much as being

   * within about 500 bytes (next page boundary)

   *
   * why snprintf?  an int is up to 12 digits long.  if we just assumed when
   * logging that a[%d]= was going to be 16 characters long we would be wasting
   * space in every audit message.  In one 7500 byte message we can log up to
   * about 1000 min size arguments.  That comes down to about 50% waste of space
   * if we didn't do the snprintf to find out how long arg_num_len was.
   */
  static int audit_log_single_execve_arg(struct audit_context *context,
  					struct audit_buffer **ab,
  					int arg_num,
  					size_t *len_sent,
  					const char __user *p,
  					char *buf)

  {

  	char arg_num_len_buf[12];
  	const char __user *tmp_p = p;

  	/* how many digits are in arg_num? 5 is the length of ' a=""' */
  	size_t arg_num_len = snprintf(arg_num_len_buf, 12, "%d", arg_num) + 5;

  	size_t len, len_left, to_send;
  	size_t max_execve_audit_len = MAX_EXECVE_AUDIT_LEN;
  	unsigned int i, has_cntl = 0, too_long = 0;
  	int ret;
  
  	/* strnlen_user includes the null we don't want to send */
  	len_left = len = strnlen_user(p, MAX_ARG_STRLEN) - 1;

  	/*
  	 * We just created this mm, if we can't find the strings
  	 * we just copied into it something is _very_ wrong. Similar
  	 * for strings that are too long, we should not have created
  	 * any.
  	 */

  	if (unlikely((len == -1) || len > MAX_ARG_STRLEN - 1)) {

  		WARN_ON(1);
  		send_sig(SIGKILL, current, 0);

  		return -1;

  	}

  	/* walk the whole argument looking for non-ascii chars */
  	do {
  		if (len_left > MAX_EXECVE_AUDIT_LEN)
  			to_send = MAX_EXECVE_AUDIT_LEN;
  		else
  			to_send = len_left;
  		ret = copy_from_user(buf, tmp_p, to_send);

  		/*

  		 * There is no reason for this copy to be short. We just
  		 * copied them here, and the mm hasn't been exposed to user-
  		 * space yet.

  		 */

  		if (ret) {

  			WARN_ON(1);
  			send_sig(SIGKILL, current, 0);

  			return -1;

  		}

  		buf[to_send] = '\0';
  		has_cntl = audit_string_contains_control(buf, to_send);
  		if (has_cntl) {
  			/*
  			 * hex messages get logged as 2 bytes, so we can only
  			 * send half as much in each message
  			 */
  			max_execve_audit_len = MAX_EXECVE_AUDIT_LEN / 2;

  			break;
  		}

  		len_left -= to_send;
  		tmp_p += to_send;
  	} while (len_left > 0);
  
  	len_left = len;
  
  	if (len > max_execve_audit_len)
  		too_long = 1;
  
  	/* rewalk the argument actually logging the message */
  	for (i = 0; len_left > 0; i++) {
  		int room_left;
  
  		if (len_left > max_execve_audit_len)
  			to_send = max_execve_audit_len;
  		else
  			to_send = len_left;
  
  		/* do we have space left to send this argument in this ab? */
  		room_left = MAX_EXECVE_AUDIT_LEN - arg_num_len - *len_sent;
  		if (has_cntl)
  			room_left -= (to_send * 2);
  		else
  			room_left -= to_send;
  		if (room_left < 0) {
  			*len_sent = 0;
  			audit_log_end(*ab);
  			*ab = audit_log_start(context, GFP_KERNEL, AUDIT_EXECVE);
  			if (!*ab)
  				return 0;
  		}

  		/*

  		 * first record needs to say how long the original string was
  		 * so we can be sure nothing was lost.
  		 */
  		if ((i == 0) && (too_long))

  			audit_log_format(*ab, " a%d_len=%zu", arg_num,

  					 has_cntl ? 2*len : len);
  
  		/*
  		 * normally arguments are small enough to fit and we already
  		 * filled buf above when we checked for control characters
  		 * so don't bother with another copy_from_user

  		 */

  		if (len >= max_execve_audit_len)
  			ret = copy_from_user(buf, p, to_send);
  		else
  			ret = 0;

  		if (ret) {

  			WARN_ON(1);
  			send_sig(SIGKILL, current, 0);

  			return -1;

  		}

  		buf[to_send] = '\0';
  
  		/* actually log it */

  		audit_log_format(*ab, " a%d", arg_num);

  		if (too_long)
  			audit_log_format(*ab, "[%d]", i);
  		audit_log_format(*ab, "=");
  		if (has_cntl)

  			audit_log_n_hex(*ab, buf, to_send);

  		else

  			audit_log_string(*ab, buf);

  
  		p += to_send;
  		len_left -= to_send;
  		*len_sent += arg_num_len;
  		if (has_cntl)
  			*len_sent += to_send * 2;
  		else
  			*len_sent += to_send;
  	}
  	/* include the null we didn't log */
  	return len + 1;
  }
  
  static void audit_log_execve_info(struct audit_context *context,
  				  struct audit_buffer **ab,
  				  struct audit_aux_data_execve *axi)
  {
  	int i;
  	size_t len, len_sent = 0;
  	const char __user *p;
  	char *buf;

  	if (axi->mm != current->mm)
  		return; /* execve failed, no additional info */
  
  	p = (const char __user *)axi->mm->arg_start;

  	audit_log_format(*ab, "argc=%d", axi->argc);

  
  	/*
  	 * we need some kernel buffer to hold the userspace args.  Just
  	 * allocate one big one rather than allocating one of the right size
  	 * for every single argument inside audit_log_single_execve_arg()
  	 * should be <8k allocation so should be pretty safe.
  	 */
  	buf = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL);
  	if (!buf) {
  		audit_panic("out of memory for argv string
  ");
  		return;

  	}

  
  	for (i = 0; i < axi->argc; i++) {
  		len = audit_log_single_execve_arg(context, ab, i,
  						  &len_sent, p, buf);
  		if (len <= 0)
  			break;
  		p += len;
  	}
  	kfree(buf);

  }

  static void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap)
  {
  	int i;
  
  	audit_log_format(ab, " %s=", prefix);
  	CAP_FOR_EACH_U32(i) {
  		audit_log_format(ab, "%08x", cap->cap[(_KERNEL_CAPABILITY_U32S-1) - i]);
  	}
  }
  
  static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name)
  {
  	kernel_cap_t *perm = &name->fcap.permitted;
  	kernel_cap_t *inh = &name->fcap.inheritable;
  	int log = 0;
  
  	if (!cap_isclear(*perm)) {
  		audit_log_cap(ab, "cap_fp", perm);
  		log = 1;
  	}
  	if (!cap_isclear(*inh)) {
  		audit_log_cap(ab, "cap_fi", inh);
  		log = 1;
  	}
  
  	if (log)
  		audit_log_format(ab, " cap_fe=%d cap_fver=%x", name->fcap.fE, name->fcap_ver);
  }

  static void show_special(struct audit_context *context, int *call_panic)

  {
  	struct audit_buffer *ab;
  	int i;
  
  	ab = audit_log_start(context, GFP_KERNEL, context->type);
  	if (!ab)
  		return;
  
  	switch (context->type) {
  	case AUDIT_SOCKETCALL: {
  		int nargs = context->socketcall.nargs;
  		audit_log_format(ab, "nargs=%d", nargs);
  		for (i = 0; i < nargs; i++)
  			audit_log_format(ab, " a%d=%lx", i,
  				context->socketcall.args[i]);
  		break; }

  	case AUDIT_IPC: {
  		u32 osid = context->ipc.osid;

  		audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho",

  			 context->ipc.uid, context->ipc.gid, context->ipc.mode);
  		if (osid) {
  			char *ctx = NULL;
  			u32 len;
  			if (security_secid_to_secctx(osid, &ctx, &len)) {
  				audit_log_format(ab, " osid=%u", osid);
  				*call_panic = 1;
  			} else {
  				audit_log_format(ab, " obj=%s", ctx);
  				security_release_secctx(ctx, len);
  			}
  		}

  		if (context->ipc.has_perm) {
  			audit_log_end(ab);
  			ab = audit_log_start(context, GFP_KERNEL,
  					     AUDIT_IPC_SET_PERM);
  			audit_log_format(ab,

  				"qbytes=%lx ouid=%u ogid=%u mode=%#ho",

  				context->ipc.qbytes,
  				context->ipc.perm_uid,
  				context->ipc.perm_gid,
  				context->ipc.perm_mode);
  			if (!ab)
  				return;
  		}

  		break; }

  	case AUDIT_MQ_OPEN: {
  		audit_log_format(ab,

  			"oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld "

  			"mq_msgsize=%ld mq_curmsgs=%ld",
  			context->mq_open.oflag, context->mq_open.mode,
  			context->mq_open.attr.mq_flags,
  			context->mq_open.attr.mq_maxmsg,
  			context->mq_open.attr.mq_msgsize,
  			context->mq_open.attr.mq_curmsgs);
  		break; }

  	case AUDIT_MQ_SENDRECV: {
  		audit_log_format(ab,
  			"mqdes=%d msg_len=%zd msg_prio=%u "
  			"abs_timeout_sec=%ld abs_timeout_nsec=%ld",
  			context->mq_sendrecv.mqdes,
  			context->mq_sendrecv.msg_len,
  			context->mq_sendrecv.msg_prio,
  			context->mq_sendrecv.abs_timeout.tv_sec,
  			context->mq_sendrecv.abs_timeout.tv_nsec);
  		break; }

  	case AUDIT_MQ_NOTIFY: {
  		audit_log_format(ab, "mqdes=%d sigev_signo=%d",
  				context->mq_notify.mqdes,
  				context->mq_notify.sigev_signo);
  		break; }

  	case AUDIT_MQ_GETSETATTR: {
  		struct mq_attr *attr = &context->mq_getsetattr.mqstat;
  		audit_log_format(ab,
  			"mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld "
  			"mq_curmsgs=%ld ",
  			context->mq_getsetattr.mqdes,
  			attr->mq_flags, attr->mq_maxmsg,
  			attr->mq_msgsize, attr->mq_curmsgs);
  		break; }

  	case AUDIT_CAPSET: {
  		audit_log_format(ab, "pid=%d", context->capset.pid);
  		audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable);
  		audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted);
  		audit_log_cap(ab, "cap_pe", &context->capset.cap.effective);
  		break; }

  	case AUDIT_MMAP: {
  		audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd,
  				 context->mmap.flags);
  		break; }

  	}
  	audit_log_end(ab);
  }

  static void audit_log_exit(struct audit_context *context, struct task_struct *tsk)

  {

  	const struct cred *cred;

  	int i, call_panic = 0;

  	struct audit_buffer *ab;

  	struct audit_aux_data *aux;

  	const char *tty;

  	/* tsk == current */

  	context->pid = tsk->pid;

  	if (!context->ppid)
  		context->ppid = sys_getppid();

  	cred = current_cred();
  	context->uid   = cred->uid;
  	context->gid   = cred->gid;
  	context->euid  = cred->euid;
  	context->suid  = cred->suid;

  	context->fsuid = cred->fsuid;

  	context->egid  = cred->egid;
  	context->sgid  = cred->sgid;

  	context->fsgid = cred->fsgid;

  	context->personality = tsk->personality;

  
  	ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);

  	if (!ab)
  		return;		/* audit_panic has been called */

  	audit_log_format(ab, "arch=%x syscall=%d",
  			 context->arch, context->major);

  	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);

  	spin_lock_irq(&tsk->sighand->siglock);

  	if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name)
  		tty = tsk->signal->tty->name;

  	else
  		tty = "(none)";

  	spin_unlock_irq(&tsk->sighand->siglock);

  	audit_log_format(ab,
  		  " a0=%lx a1=%lx a2=%lx a3=%lx items=%d"

  		  " ppid=%d pid=%d auid=%u uid=%u gid=%u"

  		  " euid=%u suid=%u fsuid=%u"

  		  " egid=%u sgid=%u fsgid=%u tty=%s ses=%u",

  		  context->argv[0],
  		  context->argv[1],
  		  context->argv[2],
  		  context->argv[3],
  		  context->name_count,

  		  context->ppid,

  		  context->pid,

  		  tsk->loginuid,

  		  context->uid,
  		  context->gid,
  		  context->euid, context->suid, context->fsuid,

  		  context->egid, context->sgid, context->fsgid, tty,
  		  tsk->sessionid);

  	audit_log_task_info(ab, tsk);

  	audit_log_key(ab, context->filterkey);

  	audit_log_end(ab);

  	for (aux = context->aux; aux; aux = aux->next) {

  		ab = audit_log_start(context, GFP_KERNEL, aux->type);

  		if (!ab)
  			continue; /* audit_panic has been called */

  		switch (aux->type) {

  		case AUDIT_EXECVE: {
  			struct audit_aux_data_execve *axi = (void *)aux;

  			audit_log_execve_info(context, &ab, axi);

  			break; }

  		case AUDIT_BPRM_FCAPS: {
  			struct audit_aux_data_bprm_fcaps *axs = (void *)aux;
  			audit_log_format(ab, "fver=%x", axs->fcap_ver);
  			audit_log_cap(ab, "fp", &axs->fcap.permitted);
  			audit_log_cap(ab, "fi", &axs->fcap.inheritable);
  			audit_log_format(ab, " fe=%d", axs->fcap.fE);
  			audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted);
  			audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable);
  			audit_log_cap(ab, "old_pe", &axs->old_pcap.effective);
  			audit_log_cap(ab, "new_pp", &axs->new_pcap.permitted);
  			audit_log_cap(ab, "new_pi", &axs->new_pcap.inheritable);
  			audit_log_cap(ab, "new_pe", &axs->new_pcap.effective);
  			break; }

  		}
  		audit_log_end(ab);

  	}

  	if (context->type)

  		show_special(context, &call_panic);

  	if (context->fds[0] >= 0) {
  		ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR);
  		if (ab) {
  			audit_log_format(ab, "fd0=%d fd1=%d",
  					context->fds[0], context->fds[1]);
  			audit_log_end(ab);
  		}
  	}

  	if (context->sockaddr_len) {
  		ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR);
  		if (ab) {
  			audit_log_format(ab, "saddr=");
  			audit_log_n_hex(ab, (void *)context->sockaddr,
  					context->sockaddr_len);
  			audit_log_end(ab);
  		}
  	}

  	for (aux = context->aux_pids; aux; aux = aux->next) {
  		struct audit_aux_data_pids *axs = (void *)aux;

  
  		for (i = 0; i < axs->pid_count; i++)
  			if (audit_log_pid_context(context, axs->target_pid[i],

  						  axs->target_auid[i],
  						  axs->target_uid[i],

  						  axs->target_sessionid[i],

  						  axs->target_sid[i],
  						  axs->target_comm[i]))

  				call_panic = 1;

  	}

  	if (context->target_pid &&
  	    audit_log_pid_context(context, context->target_pid,

  				  context->target_auid, context->target_uid,

  				  context->target_sessionid,

  				  context->target_sid, context->target_comm))

  			call_panic = 1;

  	if (context->pwd.dentry && context->pwd.mnt) {

  		ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);

  		if (ab) {

  			audit_log_d_path(ab, "cwd=", &context->pwd);

  			audit_log_end(ab);
  		}
  	}

  	for (i = 0; i < context->name_count; i++) {

  		struct audit_names *n = &context->names[i];

  		ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);

  		if (!ab)
  			continue; /* audit_panic has been called */

  		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);

  				break;
  			default:
  				/* log the name's directory component */
  				audit_log_format(ab, " name=");

  				audit_log_n_untrustedstring(ab, n->name,
  							    n->name_len);

  			}
  		} else
  			audit_log_format(ab, " name=(null)");
  
  		if (n->ino != (unsigned long)-1) {
  			audit_log_format(ab, " inode=%lu"

  					 " dev=%02x:%02x mode=%#ho"

  					 " ouid=%u ogid=%u rdev=%02x:%02x",
  					 n->ino,
  					 MAJOR(n->dev),
  					 MINOR(n->dev),
  					 n->mode,
  					 n->uid,
  					 n->gid,
  					 MAJOR(n->rdev),
  					 MINOR(n->rdev));
  		}
  		if (n->osid != 0) {

  			char *ctx = NULL;
  			u32 len;

  			if (security_secid_to_secctx(

  				n->osid, &ctx, &len)) {
  				audit_log_format(ab, " osid=%u", n->osid);

  				call_panic = 2;

  			} else {

  				audit_log_format(ab, " obj=%s", ctx);

  				security_release_secctx(ctx, len);
  			}

  		}

  		audit_log_fcaps(ab, n);

  		audit_log_end(ab);
  	}

  
  	/* Send end of event record to help user space know we are finished */
  	ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE);
  	if (ab)
  		audit_log_end(ab);

  	if (call_panic)
  		audit_panic("error converting sid to string");

  }

  /**
   * audit_free - free a per-task audit context
   * @tsk: task whose audit context block to free
   *

   * Called from copy_process and do_exit

   */

  void audit_free(struct task_struct *tsk)
  {
  	struct audit_context *context;

  	context = audit_get_context(tsk, 0, 0);

  	if (likely(!context))
  		return;
  
  	/* Check for system calls that do not go through the exit

  	 * function (e.g., exit_group), then free context block.
  	 * We use GFP_ATOMIC here because we might be doing this

  	 * in the context of the idle thread */

  	/* that can happen only if we are called from do_exit() */

  	if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)

  		audit_log_exit(context, tsk);

  	if (!list_empty(&context->killed_trees))
  		audit_kill_trees(&context->killed_trees);

  
  	audit_free_context(context);
  }

  /**
   * audit_syscall_entry - fill in an audit record at syscall entry

   * @arch: architecture type
   * @major: major syscall type (function)
   * @a1: additional syscall register 1
   * @a2: additional syscall register 2
   * @a3: additional syscall register 3
   * @a4: additional syscall register 4
   *
   * Fill in audit context at syscall entry.  This only happens if the

   * audit context was created when the task was created and the state or
   * filters demand the audit context be built.  If the state from the
   * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT,
   * then the record will be written at syscall exit time (otherwise, it
   * will only be written if another part of the kernel requests that it

   * be written).
   */

  void audit_syscall_entry(int arch, int major,

  			 unsigned long a1, unsigned long a2,
  			 unsigned long a3, unsigned long a4)
  {

  	struct task_struct *tsk = current;

  	struct audit_context *context = tsk->audit_context;
  	enum audit_state     state;

  	if (unlikely(!context))
  		return;

  	/*
  	 * This happens only on certain architectures that make system

  	 * calls in kernel_thread via the entry.S interface, instead of
  	 * with direct calls.  (If you are porting to a new
  	 * architecture, hitting this condition can indicate that you
  	 * got the _exit/_leave calls backward in entry.S.)
  	 *
  	 * i386     no
  	 * x86_64   no

  	 * ppc64    yes (see arch/powerpc/platforms/iseries/misc.S)

  	 *
  	 * This also happens with vm86 emulation in a non-nested manner
  	 * (entries without exits), so this case must be caught.
  	 */
  	if (context->in_syscall) {
  		struct audit_context *newctx;

  #if AUDIT_DEBUG
  		printk(KERN_ERR
  		       "audit(:%d) pid=%d in syscall=%d;"
  		       " entering syscall=%d
  ",
  		       context->serial, tsk->pid, context->major, major);
  #endif
  		newctx = audit_alloc_context(context->state);
  		if (newctx) {
  			newctx->previous   = context;
  			context		   = newctx;
  			tsk->audit_context = newctx;
  		} else	{
  			/* If we can't alloc a new context, the best we
  			 * can do is to leak memory (any pending putname
  			 * will be lost).  The only other alternative is
  			 * to abandon auditing. */
  			audit_zero_context(context, context->state);
  		}
  	}
  	BUG_ON(context->in_syscall || context->name_count);
  
  	if (!audit_enabled)
  		return;

  	context->arch	    = arch;

  	context->major      = major;
  	context->argv[0]    = a1;
  	context->argv[1]    = a2;
  	context->argv[2]    = a3;
  	context->argv[3]    = a4;
  
  	state = context->state;

  	context->dummy = !audit_n_rules;

  	if (!context->dummy && state == AUDIT_BUILD_CONTEXT) {
  		context->prio = 0;

  		state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]);

  	}

  	if (likely(state == AUDIT_DISABLED))
  		return;

  	context->serial     = 0;

  	context->ctime      = CURRENT_TIME;
  	context->in_syscall = 1;

  	context->current_state  = state;

  	context->ppid       = 0;

  }

  void audit_finish_fork(struct task_struct *child)
  {
  	struct audit_context *ctx = current->audit_context;
  	struct audit_context *p = child->audit_context;

  	if (!p || !ctx)
  		return;
  	if (!ctx->in_syscall || ctx->current_state != AUDIT_RECORD_CONTEXT)

  		return;
  	p->arch = ctx->arch;
  	p->major = ctx->major;
  	memcpy(p->argv, ctx->argv, sizeof(ctx->argv));
  	p->ctime = ctx->ctime;
  	p->dummy = ctx->dummy;

  	p->in_syscall = ctx->in_syscall;
  	p->filterkey = kstrdup(ctx->filterkey, GFP_KERNEL);
  	p->ppid = current->pid;

  	p->prio = ctx->prio;
  	p->current_state = ctx->current_state;

  }

  /**
   * audit_syscall_exit - deallocate audit context after a system call

   * @valid: success/failure flag
   * @return_code: syscall return value
   *
   * Tear down after system call.  If the audit context has been marked as

   * auditable (either because of the AUDIT_RECORD_CONTEXT state from
   * filtering, or because some other part of the kernel write an audit
   * message), then write out the syscall information.  In call cases,

   * free the names stored from getname().
   */

  void audit_syscall_exit(int valid, long return_code)

  {

  	struct task_struct *tsk = current;

  	struct audit_context *context;

  	context = audit_get_context(tsk, valid, return_code);

  	if (likely(!context))

  		return;

  	if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)

  		audit_log_exit(context, tsk);

  
  	context->in_syscall = 0;

  	context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;

  	if (!list_empty(&context->killed_trees))
  		audit_kill_trees(&context->killed_trees);

  	if (context->previous) {
  		struct audit_context *new_context = context->previous;
  		context->previous  = NULL;
  		audit_free_context(context);
  		tsk->audit_context = new_context;
  	} else {
  		audit_free_names(context);

  		unroll_tree_refs(context, NULL, 0);

  		audit_free_aux(context);

  		context->aux = NULL;
  		context->aux_pids = NULL;

  		context->target_pid = 0;

  		context->target_sid = 0;

  		context->sockaddr_len = 0;

  		context->type = 0;

  		context->fds[0] = -1;

  		if (context->state != AUDIT_RECORD_CONTEXT) {
  			kfree(context->filterkey);
  			context->filterkey = NULL;
  		}

  		tsk->audit_context = context;
  	}

  }

  static inline void handle_one(const struct inode *inode)
  {
  #ifdef CONFIG_AUDIT_TREE
  	struct audit_context *context;
  	struct audit_tree_refs *p;
  	struct audit_chunk *chunk;
  	int count;

  	if (likely(hlist_empty(&inode->i_fsnotify_marks)))

  		return;
  	context = current->audit_context;
  	p = context->trees;
  	count = context->tree_count;
  	rcu_read_lock();
  	chunk = audit_tree_lookup(inode);
  	rcu_read_unlock();
  	if (!chunk)
  		return;
  	if (likely(put_tree_ref(context, chunk)))
  		return;
  	if (unlikely(!grow_tree_refs(context))) {

  		printk(KERN_WARNING "out of memory, audit has lost a tree reference
  ");

  		audit_set_auditable(context);
  		audit_put_chunk(chunk);
  		unroll_tree_refs(context, p, count);
  		return;
  	}
  	put_tree_ref(context, chunk);
  #endif
  }
  
  static void handle_path(const struct dentry *dentry)
  {
  #ifdef CONFIG_AUDIT_TREE
  	struct audit_context *context;
  	struct audit_tree_refs *p;
  	const struct dentry *d, *parent;
  	struct audit_chunk *drop;
  	unsigned long seq;
  	int count;
  
  	context = current->audit_context;
  	p = context->trees;
  	count = context->tree_count;
  retry:
  	drop = NULL;
  	d = dentry;
  	rcu_read_lock();
  	seq = read_seqbegin(&rename_lock);
  	for(;;) {
  		struct inode *inode = d->d_inode;

  		if (inode && unlikely(!hlist_empty(&inode->i_fsnotify_marks))) {

  			struct audit_chunk *chunk;
  			chunk = audit_tree_lookup(inode);
  			if (chunk) {
  				if (unlikely(!put_tree_ref(context, chunk))) {
  					drop = chunk;
  					break;
  				}
  			}
  		}
  		parent = d->d_parent;
  		if (parent == d)
  			break;
  		d = parent;
  	}
  	if (unlikely(read_seqretry(&rename_lock, seq) || drop)) {  /* in this order */
  		rcu_read_unlock();
  		if (!drop) {
  			/* just a race with rename */
  			unroll_tree_refs(context, p, count);
  			goto retry;
  		}
  		audit_put_chunk(drop);
  		if (grow_tree_refs(context)) {
  			/* OK, got more space */
  			unroll_tree_refs(context, p, count);
  			goto retry;
  		}
  		/* too bad */
  		printk(KERN_WARNING

  			"out of memory, audit has lost a tree reference
  ");

  		unroll_tree_refs(context, p, count);
  		audit_set_auditable(context);
  		return;
  	}
  	rcu_read_unlock();
  #endif
  }

  /**
   * audit_getname - add a name to the list
   * @name: name to add
   *
   * Add a name to the list of audit names for this context.
   * Called from fs/namei.c:getname().
   */

  void __audit_getname(const char *name)

  {
  	struct audit_context *context = current->audit_context;

  	if (IS_ERR(name) || !name)

  		return;
  
  	if (!context->in_syscall) {
  #if AUDIT_DEBUG == 2
  		printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)
  ",
  		       __FILE__, __LINE__, context->serial, name);
  		dump_stack();
  #endif
  		return;
  	}
  	BUG_ON(context->name_count >= AUDIT_NAMES);
  	context->names[context->name_count].name = name;

  	context->names[context->name_count].name_len = AUDIT_NAME_FULL;
  	context->names[context->name_count].name_put = 1;

  	context->names[context->name_count].ino  = (unsigned long)-1;

  	context->names[context->name_count].osid = 0;

  	++context->name_count;

  	if (!context->pwd.dentry)
  		get_fs_pwd(current->fs, &context->pwd);

  }

  /* audit_putname - intercept a putname request
   * @name: name to intercept and delay for putname
   *
   * If we have stored the name from getname in the audit context,
   * then we delay the putname until syscall exit.
   * Called from include/linux/fs.h:putname().
   */

  void audit_putname(const char *name)
  {
  	struct audit_context *context = current->audit_context;
  
  	BUG_ON(!context);
  	if (!context->in_syscall) {
  #if AUDIT_DEBUG == 2
  		printk(KERN_ERR "%s:%d(:%d): __putname(%p)
  ",
  		       __FILE__, __LINE__, context->serial, name);
  		if (context->name_count) {
  			int i;
  			for (i = 0; i < context->name_count; i++)
  				printk(KERN_ERR "name[%d] = %p = %s
  ", i,
  				       context->names[i].name,

  				       context->names[i].name ?: "(null)");

  		}
  #endif
  		__putname(name);
  	}
  #if AUDIT_DEBUG
  	else {
  		++context->put_count;
  		if (context->put_count > context->name_count) {
  			printk(KERN_ERR "%s:%d(:%d): major=%d"
  			       " in_syscall=%d putname(%p) name_count=%d"
  			       " put_count=%d
  ",
  			       __FILE__, __LINE__,
  			       context->serial, context->major,
  			       context->in_syscall, name, context->name_count,
  			       context->put_count);
  			dump_stack();
  		}
  	}
  #endif
  }

  static int audit_inc_name_count(struct audit_context *context,
  				const struct inode *inode)
  {
  	if (context->name_count >= AUDIT_NAMES) {
  		if (inode)

  			printk(KERN_DEBUG "audit: name_count maxed, losing inode data: "

  			       "dev=%02x:%02x, inode=%lu
  ",

  			       MAJOR(inode->i_sb->s_dev),
  			       MINOR(inode->i_sb->s_dev),
  			       inode->i_ino);
  
  		else

  			printk(KERN_DEBUG "name_count maxed, losing inode data
  ");

  		return 1;
  	}
  	context->name_count++;
  #if AUDIT_DEBUG
  	context->ino_count++;
  #endif
  	return 0;
  }

  
  static inline int audit_copy_fcaps(struct audit_names *name, const struct dentry *dentry)
  {
  	struct cpu_vfs_cap_data caps;
  	int rc;
  
  	memset(&name->fcap.permitted, 0, sizeof(kernel_cap_t));
  	memset(&name->fcap.inheritable, 0, sizeof(kernel_cap_t));
  	name->fcap.fE = 0;
  	name->fcap_ver = 0;
  
  	if (!dentry)
  		return 0;
  
  	rc = get_vfs_caps_from_disk(dentry, &caps);
  	if (rc)
  		return rc;
  
  	name->fcap.permitted = caps.permitted;
  	name->fcap.inheritable = caps.inheritable;
  	name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
  	name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT;
  
  	return 0;
  }

  /* Copy inode data into an audit_names. */

  static void audit_copy_inode(struct audit_names *name, const struct dentry *dentry,
  			     const struct inode *inode)

  {

  	name->ino   = inode->i_ino;
  	name->dev   = inode->i_sb->s_dev;
  	name->mode  = inode->i_mode;
  	name->uid   = inode->i_uid;
  	name->gid   = inode->i_gid;
  	name->rdev  = inode->i_rdev;

  	security_inode_getsecid(inode, &name->osid);

  	audit_copy_fcaps(name, dentry);

  }

  /**
   * audit_inode - store the inode and device from a lookup
   * @name: name being audited

   * @dentry: dentry being audited

   *
   * Called from fs/namei.c:path_lookup().
   */