1 files changed, 169 insertions, 62 deletions

diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index e75f84e1a1a0..46b45abceb9a 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -39,6 +39,9 @@
 #include <linux/audit.h>
 #include <linux/personality.h>
 #include <linux/time.h>
+#include <linux/kthread.h>
+#include <linux/netlink.h>
+#include <linux/compiler.h>
 #include <asm/unistd.h>
 
 /* 0 = no checking
@@ -95,6 +98,7 @@ struct audit_names {
         uid_t           uid;
         gid_t           gid;
         dev_t           rdev;
+        unsigned        flags;
 };
 
 struct audit_aux_data {
@@ -167,9 +171,16 @@ struct audit_context {
 /* There are three lists of rules -- one to search at task creation
  * time, one to search at syscall entry time, and another to search at
  * syscall exit time. */
-static LIST_HEAD(audit_tsklist);
-static LIST_HEAD(audit_entlist);
-static LIST_HEAD(audit_extlist);
+static struct list_head audit_filter_list[AUDIT_NR_FILTERS] = {
+        LIST_HEAD_INIT(audit_filter_list[0]),
+        LIST_HEAD_INIT(audit_filter_list[1]),
+        LIST_HEAD_INIT(audit_filter_list[2]),
+        LIST_HEAD_INIT(audit_filter_list[3]),
+        LIST_HEAD_INIT(audit_filter_list[4]),
+#if AUDIT_NR_FILTERS != 5
+#error Fix audit_filter_list initialiser
+#endif
+};
 
 struct audit_entry {
         struct list_head  list;
@@ -210,16 +221,15 @@ static int audit_compare_rule(struct audit_rule *a, struct audit_rule *b)
 /* Note that audit_add_rule and audit_del_rule are called via
  * audit_receive() in audit.c, and are protected by
  * audit_netlink_sem. */
-static inline int audit_add_rule(struct audit_entry *entry,
-                                 struct list_head *list)
+static inline void audit_add_rule(struct audit_entry *entry,
+                                  struct list_head *list)
 {
-        if (entry->rule.flags & AUDIT_PREPEND) {
-                entry->rule.flags &= ~AUDIT_PREPEND;
+        if (entry->rule.flags & AUDIT_FILTER_PREPEND) {
+                entry->rule.flags &= ~AUDIT_FILTER_PREPEND;
                 list_add_rcu(&entry->list, list);
         } else {
                 list_add_tail_rcu(&entry->list, list);
         }
-        return 0;
 }
 
 static void audit_free_rule(struct rcu_head *head)
@@ -245,7 +255,7 @@ static inline int audit_del_rule(struct audit_rule *rule,
                         return 0;
                 }
         }
-        return -EFAULT;         /* No matching rule */
+        return -ENOENT;         /* No matching rule */
 }
 
 /* Copy rule from user-space to kernel-space.  Called during
@@ -260,6 +270,8 @@ static int audit_copy_rule(struct audit_rule *d, struct audit_rule *s)
                 return -1;
         if (s->field_count < 0 || s->field_count > AUDIT_MAX_FIELDS)
                 return -1;
+        if ((s->flags & ~AUDIT_FILTER_PREPEND) >= AUDIT_NR_FILTERS)
+                return -1;
 
         d->flags        = s->flags;
         d->action       = s->action;
@@ -272,27 +284,60 @@ static int audit_copy_rule(struct audit_rule *d, struct audit_rule *s)
         return 0;
 }
 
+static int audit_list_rules(void *_dest)
+{
+        int pid, seq;
+        int *dest = _dest;
+        struct audit_entry *entry;
+        int i;
+
+        pid = dest[0];
+        seq = dest[1];
+        kfree(dest);
+
+        down(&audit_netlink_sem);
+
+        /* The *_rcu iterators not needed here because we are
+           always called with audit_netlink_sem held. */
+        for (i=0; i<AUDIT_NR_FILTERS; i++) {
+                list_for_each_entry(entry, &audit_filter_list[i], list)
+                        audit_send_reply(pid, seq, AUDIT_LIST, 0, 1,
+                                         &entry->rule, sizeof(entry->rule));
+        }
+        audit_send_reply(pid, seq, AUDIT_LIST, 1, 1, NULL, 0);
+        
+        up(&audit_netlink_sem);
+        return 0;
+}
+
 int audit_receive_filter(int type, int pid, int uid, int seq, void *data,
                                                         uid_t loginuid)
 {
-        u32                flags;
         struct audit_entry *entry;
+        struct task_struct *tsk;
+        int *dest;
         int                err = 0;
+        unsigned listnr;
 
         switch (type) {
         case AUDIT_LIST:
-                /* The *_rcu iterators not needed here because we are
-                   always called with audit_netlink_sem held. */
-                list_for_each_entry(entry, &audit_tsklist, list)
-                        audit_send_reply(pid, seq, AUDIT_LIST, 0, 1,
-                                         &entry->rule, sizeof(entry->rule));
-                list_for_each_entry(entry, &audit_entlist, list)
-                        audit_send_reply(pid, seq, AUDIT_LIST, 0, 1,
-                                         &entry->rule, sizeof(entry->rule));
-                list_for_each_entry(entry, &audit_extlist, list)
-                        audit_send_reply(pid, seq, AUDIT_LIST, 0, 1,
-                                         &entry->rule, sizeof(entry->rule));
-                audit_send_reply(pid, seq, AUDIT_LIST, 1, 1, NULL, 0);
+                /* We can't just spew out the rules here because we might fill
+                 * the available socket buffer space and deadlock waiting for
+                 * auditctl to read from it... which isn't ever going to
+                 * happen if we're actually running in the context of auditctl
+                 * trying to _send_ the stuff */
+                 
+                dest = kmalloc(2 * sizeof(int), GFP_KERNEL);
+                if (!dest)
+                        return -ENOMEM;
+                dest[0] = pid;
+                dest[1] = seq;
+
+                tsk = kthread_run(audit_list_rules, dest, "audit_list_rules");
+                if (IS_ERR(tsk)) {
+                        kfree(dest);
+                        err = PTR_ERR(tsk);
+                }
                 break;
         case AUDIT_ADD:
                 if (!(entry = kmalloc(sizeof(*entry), GFP_KERNEL)))
@@ -301,26 +346,20 @@ int audit_receive_filter(int type, int pid, int uid, int seq, void *data,
                         kfree(entry);
                         return -EINVAL;
                 }
-                flags = entry->rule.flags;
-                if (!err && (flags & AUDIT_PER_TASK))
-                        err = audit_add_rule(entry, &audit_tsklist);
-                if (!err && (flags & AUDIT_AT_ENTRY))
-                        err = audit_add_rule(entry, &audit_entlist);
-                if (!err && (flags & AUDIT_AT_EXIT))
-                        err = audit_add_rule(entry, &audit_extlist);
-                audit_log(NULL, AUDIT_CONFIG_CHANGE, 
+                listnr = entry->rule.flags & ~AUDIT_FILTER_PREPEND;
+                audit_add_rule(entry, &audit_filter_list[listnr]);
+                audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE, 
                                 "auid=%u added an audit rule\n", loginuid);
                 break;
         case AUDIT_DEL:
-                flags =((struct audit_rule *)data)->flags;
-                if (!err && (flags & AUDIT_PER_TASK))
-                        err = audit_del_rule(data, &audit_tsklist);
-                if (!err && (flags & AUDIT_AT_ENTRY))
-                        err = audit_del_rule(data, &audit_entlist);
-                if (!err && (flags & AUDIT_AT_EXIT))
-                        err = audit_del_rule(data, &audit_extlist);
-                audit_log(NULL, AUDIT_CONFIG_CHANGE,
-                                "auid=%u removed an audit rule\n", loginuid);
+                listnr =((struct audit_rule *)data)->flags & ~AUDIT_FILTER_PREPEND;
+                if (listnr >= AUDIT_NR_FILTERS)
+                        return -EINVAL;
+
+                err = audit_del_rule(data, &audit_filter_list[listnr]);
+                if (!err)
+                        audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
+                                  "auid=%u removed an audit rule\n", loginuid);
                 break;
         default:
                 return -EINVAL;
@@ -454,7 +493,7 @@ static enum audit_state audit_filter_task(struct task_struct *tsk)
         enum audit_state   state;
 
         rcu_read_lock();
-        list_for_each_entry_rcu(e, &audit_tsklist, list) {
+        list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
                 if (audit_filter_rules(tsk, &e->rule, NULL, &state)) {
                         rcu_read_unlock();
                         return state;
@@ -478,6 +517,9 @@ static enum audit_state audit_filter_syscall(struct task_struct *tsk,
         int                word = AUDIT_WORD(ctx->major);
         int                bit  = AUDIT_BIT(ctx->major);
 
+        if (audit_pid && tsk->tgid == audit_pid)
+                return AUDIT_DISABLED;
+
         rcu_read_lock();
         list_for_each_entry_rcu(e, list, list) {
                 if ((e->rule.mask[word] & bit) == bit
@@ -490,6 +532,64 @@ static enum audit_state audit_filter_syscall(struct task_struct *tsk,
         return AUDIT_BUILD_CONTEXT;
 }
 
+static int audit_filter_user_rules(struct netlink_skb_parms *cb,
+                              struct audit_rule *rule,
+                              enum audit_state *state)
+{
+        int i;
+
+        for (i = 0; i < rule->field_count; i++) {
+                u32 field  = rule->fields[i] & ~AUDIT_NEGATE;
+                u32 value  = rule->values[i];
+                int result = 0;
+
+                switch (field) {
+                case AUDIT_PID:
+                        result = (cb->creds.pid == value);
+                        break;
+                case AUDIT_UID:
+                        result = (cb->creds.uid == value);
+                        break;
+                case AUDIT_GID:
+                        result = (cb->creds.gid == value);
+                        break;
+                case AUDIT_LOGINUID:
+                        result = (cb->loginuid == value);
+                        break;
+                }
+
+                if (rule->fields[i] & AUDIT_NEGATE)
+                        result = !result;
+                if (!result)
+                        return 0;
+        }
+        switch (rule->action) {
+        case AUDIT_NEVER:    *state = AUDIT_DISABLED;       break;
+        case AUDIT_POSSIBLE: *state = AUDIT_BUILD_CONTEXT;  break;
+        case AUDIT_ALWAYS:   *state = AUDIT_RECORD_CONTEXT; break;
+        }
+        return 1;
+}
+
+int audit_filter_user(struct netlink_skb_parms *cb, int type)
+{
+        struct audit_entry *e;
+        enum audit_state   state;
+        int ret = 1;
+
+        rcu_read_lock();
+        list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_USER], list) {
+                if (audit_filter_user_rules(cb, &e->rule, &state)) {
+                        if (state == AUDIT_DISABLED)
+                                ret = 0;
+                        break;
+                }
+        }
+        rcu_read_unlock();
+
+        return ret; /* Audit by default */
+}
+
 /* This should be called with task_lock() held. */
 static inline struct audit_context *audit_get_context(struct task_struct *tsk,
                                                       int return_valid,
@@ -504,7 +604,7 @@ static inline struct audit_context *audit_get_context(struct task_struct *tsk,
 
         if (context->in_syscall && !context->auditable) {
                 enum audit_state state;
-                state = audit_filter_syscall(tsk, context, &audit_extlist);
+                state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]);
                 if (state == AUDIT_RECORD_CONTEXT)
                         context->auditable = 1;
         }
@@ -679,13 +779,13 @@ static void audit_log_task_info(struct audit_buffer *ab)
         up_read(&mm->mmap_sem);
 }
 
-static void audit_log_exit(struct audit_context *context)
+static void audit_log_exit(struct audit_context *context, unsigned int gfp_mask)
 {
         int i;
         struct audit_buffer *ab;
         struct audit_aux_data *aux;
 
-        ab = audit_log_start(context, AUDIT_SYSCALL);
+        ab = audit_log_start(context, gfp_mask, AUDIT_SYSCALL);
         if (!ab)
                 return;         /* audit_panic has been called */
         audit_log_format(ab, "arch=%x syscall=%d",
@@ -717,7 +817,7 @@ static void audit_log_exit(struct audit_context *context)
 
         for (aux = context->aux; aux; aux = aux->next) {
 
-                ab = audit_log_start(context, aux->type);
+                ab = audit_log_start(context, GFP_KERNEL, aux->type);
                 if (!ab)
                         continue; /* audit_panic has been called */
 
@@ -754,14 +854,14 @@ static void audit_log_exit(struct audit_context *context)
         }
 
         if (context->pwd && context->pwdmnt) {
-                ab = audit_log_start(context, AUDIT_CWD);
+                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);
                 }
         }
         for (i = 0; i < context->name_count; i++) {
-                ab = audit_log_start(context, AUDIT_PATH);
+                ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);
                 if (!ab)
                         continue; /* audit_panic has been called */
 
@@ -770,6 +870,8 @@ static void audit_log_exit(struct audit_context *context)
                         audit_log_format(ab, " name=");
                         audit_log_untrustedstring(ab, context->names[i].name);
                 }
+                audit_log_format(ab, " flags=%x\n", context->names[i].flags);
+                         
                 if (context->names[i].ino != (unsigned long)-1)
                         audit_log_format(ab, " inode=%lu dev=%02x:%02x mode=%#o"
                                              " ouid=%u ogid=%u rdev=%02x:%02x",
@@ -799,9 +901,11 @@ void audit_free(struct task_struct *tsk)
                 return;
 
         /* Check for system calls that do not go through the exit
-         * function (e.g., exit_group), then free context block. */
-        if (context->in_syscall && context->auditable && context->pid != audit_pid)
-                audit_log_exit(context);
+         * 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 */
+        if (context->in_syscall && context->auditable)
+                audit_log_exit(context, GFP_ATOMIC);
 
         audit_free_context(context);
 }
@@ -876,11 +980,11 @@ void audit_syscall_entry(struct task_struct *tsk, int arch, int major,
 
         state = context->state;
         if (state == AUDIT_SETUP_CONTEXT || state == AUDIT_BUILD_CONTEXT)
-                state = audit_filter_syscall(tsk, context, &audit_entlist);
+                state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]);
         if (likely(state == AUDIT_DISABLED))
                 return;
 
-        context->serial     = audit_serial();
+        context->serial     = 0;
         context->ctime      = CURRENT_TIME;
         context->in_syscall = 1;
         context->auditable  = !!(state == AUDIT_RECORD_CONTEXT);
@@ -905,8 +1009,8 @@ void audit_syscall_exit(struct task_struct *tsk, int valid, long return_code)
         if (likely(!context))
                 return;
 
-        if (context->in_syscall && context->auditable && context->pid != audit_pid)
-                audit_log_exit(context);
+        if (context->in_syscall && context->auditable)
+                audit_log_exit(context, GFP_KERNEL);
 
         context->in_syscall = 0;
         context->auditable  = 0;
@@ -996,7 +1100,7 @@ void audit_putname(const char *name)
 
 /* Store the inode and device from a lookup.  Called from
  * fs/namei.c:path_lookup(). */
-void audit_inode(const char *name, const struct inode *inode)
+void audit_inode(const char *name, const struct inode *inode, unsigned flags)
 {
         int idx;
         struct audit_context *context = current->audit_context;
@@ -1022,17 +1126,20 @@ void audit_inode(const char *name, const struct inode *inode)
                 ++context->ino_count;
 #endif
         }
-        context->names[idx].ino  = inode->i_ino;
-        context->names[idx].dev  = inode->i_sb->s_dev;
-        context->names[idx].mode = inode->i_mode;
-        context->names[idx].uid  = inode->i_uid;
-        context->names[idx].gid  = inode->i_gid;
-        context->names[idx].rdev = inode->i_rdev;
+        context->names[idx].flags = flags;
+        context->names[idx].ino   = inode->i_ino;
+        context->names[idx].dev   = inode->i_sb->s_dev;
+        context->names[idx].mode  = inode->i_mode;
+        context->names[idx].uid   = inode->i_uid;
+        context->names[idx].gid   = inode->i_gid;
+        context->names[idx].rdev  = inode->i_rdev;
 }
 
 void auditsc_get_stamp(struct audit_context *ctx,
                        struct timespec *t, unsigned int *serial)
 {
+        if (!ctx->serial)
+                ctx->serial = audit_serial();
         t->tv_sec  = ctx->ctime.tv_sec;
         t->tv_nsec = ctx->ctime.tv_nsec;
         *serial    = ctx->serial;
@@ -1044,7 +1151,7 @@ int audit_set_loginuid(struct task_struct *task, uid_t loginuid)
         if (task->audit_context) {
                 struct audit_buffer *ab;
 
-                ab = audit_log_start(NULL, AUDIT_LOGIN);
+                ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
                 if (ab) {
                         audit_log_format(ab, "login pid=%d uid=%u "
                                 "old auid=%u new auid=%u",
@@ -1153,7 +1260,7 @@ void audit_signal_info(int sig, struct task_struct *t)
         extern pid_t audit_sig_pid;
         extern uid_t audit_sig_uid;
 
-        if (unlikely(audit_pid && t->pid == audit_pid)) {
+        if (unlikely(audit_pid && t->tgid == audit_pid)) {
                 if (sig == SIGTERM || sig == SIGHUP) {
                         struct audit_context *ctx = current->audit_context;
                         audit_sig_pid = current->pid;