userns: Add user namespace support to IMA
Eric W. Biederman [Sat, 26 May 2012 00:24:12 +0000 (18:24 -0600)]
Use kuid's in the IMA rules.

When reporting the current uid in audit logs use from_kuid
to get a usable value.

Cc: Mimi Zohar <zohar@us.ibm.com>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

init/Kconfig
security/integrity/ima/ima_audit.c
security/integrity/ima/ima_policy.c

index 96ee3f3..570cd33 100644 (file)
@@ -923,10 +923,6 @@ config UIDGID_CONVERTED
        bool
        default y
 
-       # List of kernel pieces that need user namespace work
-       # Features
-       depends on IMA = n
-
        # Networking
        depends on NET_9P = n
 
index 7a57f67..c586faa 100644 (file)
@@ -39,8 +39,9 @@ void integrity_audit_msg(int audit_msgno, struct inode *inode,
 
        ab = audit_log_start(current->audit_context, GFP_KERNEL, audit_msgno);
        audit_log_format(ab, "pid=%d uid=%u auid=%u ses=%u",
-                        current->pid, current_cred()->uid,
-                        audit_get_loginuid(current),
+                        current->pid,
+                        from_kuid(&init_user_ns, current_cred()->uid),
+                        from_kuid(&init_user_ns, audit_get_loginuid(current)),
                         audit_get_sessionid(current));
        audit_log_task_context(ab);
        audit_log_format(ab, " op=");
index 1a95830..c84df05 100644 (file)
@@ -39,7 +39,7 @@ struct ima_measure_rule_entry {
        enum ima_hooks func;
        int mask;
        unsigned long fsmagic;
-       uid_t uid;
+       kuid_t uid;
        struct {
                void *rule;     /* LSM file metadata specific */
                int type;       /* audit type */
@@ -71,7 +71,7 @@ static struct ima_measure_rule_entry default_rules[] = {
         .flags = IMA_FUNC | IMA_MASK},
        {.action = MEASURE,.func = BPRM_CHECK,.mask = MAY_EXEC,
         .flags = IMA_FUNC | IMA_MASK},
-       {.action = MEASURE,.func = FILE_CHECK,.mask = MAY_READ,.uid = 0,
+       {.action = MEASURE,.func = FILE_CHECK,.mask = MAY_READ,.uid = GLOBAL_ROOT_UID,
         .flags = IMA_FUNC | IMA_MASK | IMA_UID},
 };
 
@@ -112,7 +112,7 @@ static bool ima_match_rules(struct ima_measure_rule_entry *rule,
        if ((rule->flags & IMA_FSMAGIC)
            && rule->fsmagic != inode->i_sb->s_magic)
                return false;
-       if ((rule->flags & IMA_UID) && rule->uid != cred->uid)
+       if ((rule->flags & IMA_UID) && !uid_eq(rule->uid, cred->uid))
                return false;
        for (i = 0; i < MAX_LSM_RULES; i++) {
                int rc = 0;
@@ -277,7 +277,7 @@ static int ima_parse_rule(char *rule, struct ima_measure_rule_entry *entry)
 
        ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_INTEGRITY_RULE);
 
-       entry->uid = -1;
+       entry->uid = INVALID_UID;
        entry->action = UNKNOWN;
        while ((p = strsep(&rule, " \t")) != NULL) {
                substring_t args[MAX_OPT_ARGS];
@@ -361,15 +361,15 @@ static int ima_parse_rule(char *rule, struct ima_measure_rule_entry *entry)
                case Opt_uid:
                        ima_log_string(ab, "uid", args[0].from);
 
-                       if (entry->uid != -1) {
+                       if (uid_valid(entry->uid)) {
                                result = -EINVAL;
                                break;
                        }
 
                        result = strict_strtoul(args[0].from, 10, &lnum);
                        if (!result) {
-                               entry->uid = (uid_t) lnum;
-                               if (entry->uid != lnum)
+                               entry->uid = make_kuid(current_user_ns(), (uid_t)lnum);
+                               if (!uid_valid(entry->uid) || (((uid_t)lnum) != lnum))
                                        result = -EINVAL;
                                else
                                        entry->flags |= IMA_UID;