diff options
Diffstat (limited to 'security/smack/smackfs.c')
-rw-r--r-- | security/smack/smackfs.c | 116 |
1 files changed, 69 insertions, 47 deletions
diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c index 4aa12c8d3c63..3e4242617eea 100644 --- a/security/smack/smackfs.c +++ b/security/smack/smackfs.c @@ -338,8 +338,7 @@ static int smk_perm_from_str(const char *string) * @import: if non-zero, import labels * @len: label length limit * - * Returns 0 on success, -EINVAL on failure and -ENOENT when either subject - * or object is missing. + * Returns 0 on success, appropriate error code on failure. */ static int smk_fill_rule(const char *subject, const char *object, const char *access1, const char *access2, @@ -351,16 +350,16 @@ static int smk_fill_rule(const char *subject, const char *object, if (import) { rule->smk_subject = smk_import_entry(subject, len); - if (rule->smk_subject == NULL) - return -EINVAL; + if (IS_ERR(rule->smk_subject)) + return PTR_ERR(rule->smk_subject); rule->smk_object = smk_import_entry(object, len); - if (rule->smk_object == NULL) - return -EINVAL; + if (IS_ERR(rule->smk_object)) + return PTR_ERR(rule->smk_object); } else { cp = smk_parse_smack(subject, len); - if (cp == NULL) - return -EINVAL; + if (IS_ERR(cp)) + return PTR_ERR(cp); skp = smk_find_entry(cp); kfree(cp); if (skp == NULL) @@ -368,8 +367,8 @@ static int smk_fill_rule(const char *subject, const char *object, rule->smk_subject = skp; cp = smk_parse_smack(object, len); - if (cp == NULL) - return -EINVAL; + if (IS_ERR(cp)) + return PTR_ERR(cp); skp = smk_find_entry(cp); kfree(cp); if (skp == NULL) @@ -412,7 +411,7 @@ static int smk_parse_rule(const char *data, struct smack_parsed_rule *rule, * @import: if non-zero, import labels * @tokens: numer of substrings expected in data * - * Returns number of processed bytes on success, -1 on failure. + * Returns number of processed bytes on success, -ERRNO on failure. */ static ssize_t smk_parse_long_rule(char *data, struct smack_parsed_rule *rule, int import, int tokens) @@ -431,7 +430,7 @@ static ssize_t smk_parse_long_rule(char *data, struct smack_parsed_rule *rule, if (data[cnt] == '\0') /* Unexpected end of data */ - return -1; + return -EINVAL; tok[i] = data + cnt; @@ -529,14 +528,14 @@ static ssize_t smk_write_rules_list(struct file *file, const char __user *buf, while (cnt < count) { if (format == SMK_FIXED24_FMT) { rc = smk_parse_rule(data, &rule, 1); - if (rc != 0) { - rc = -EINVAL; + if (rc < 0) goto out; - } cnt = count; } else { rc = smk_parse_long_rule(data + cnt, &rule, 1, tokens); - if (rc <= 0) { + if (rc < 0) + goto out; + if (rc == 0) { rc = -EINVAL; goto out; } @@ -915,8 +914,10 @@ static ssize_t smk_set_cipso(struct file *file, const char __user *buf, mutex_lock(&smack_cipso_lock); skp = smk_import_entry(rule, 0); - if (skp == NULL) + if (IS_ERR(skp)) { + rc = PTR_ERR(skp); goto out; + } if (format == SMK_FIXED24_FMT) rule += SMK_LABELLEN; @@ -1237,8 +1238,8 @@ static ssize_t smk_write_netlbladdr(struct file *file, const char __user *buf, */ if (smack[0] != '-') { skp = smk_import_entry(smack, 0); - if (skp == NULL) { - rc = -EINVAL; + if (IS_ERR(skp)) { + rc = PTR_ERR(skp); goto free_out; } } else { @@ -1619,8 +1620,8 @@ static ssize_t smk_write_ambient(struct file *file, const char __user *buf, } skp = smk_import_entry(data, count); - if (skp == NULL) { - rc = -EINVAL; + if (IS_ERR(skp)) { + rc = PTR_ERR(skp); goto out; } @@ -1704,21 +1705,31 @@ static ssize_t smk_write_onlycap(struct file *file, const char __user *buf, if (data == NULL) return -ENOMEM; + if (copy_from_user(data, buf, count) != 0) { + rc = -EFAULT; + goto freeout; + } + /* - * Should the null string be passed in unset the onlycap value. - * This seems like something to be careful with as usually - * smk_import only expects to return NULL for errors. It - * is usually the case that a nullstring or "\n" would be - * bad to pass to smk_import but in fact this is useful here. + * Clear the smack_onlycap on invalid label errors. This means + * that we can pass a null string to unset the onlycap value. * - * smk_import will also reject a label beginning with '-', + * Importing will also reject a label beginning with '-', * so "-usecapabilities" will also work. + * + * But do so only on invalid label, not on system errors. */ - if (copy_from_user(data, buf, count) != 0) - rc = -EFAULT; - else - smack_onlycap = smk_import_entry(data, count); + skp = smk_import_entry(data, count); + if (PTR_ERR(skp) == -EINVAL) + skp = NULL; + else if (IS_ERR(skp)) { + rc = PTR_ERR(skp); + goto freeout; + } + + smack_onlycap = skp; +freeout: kfree(data); return rc; } @@ -1773,6 +1784,7 @@ static ssize_t smk_write_unconfined(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { char *data; + struct smack_known *skp; int rc = count; if (!smack_privileged(CAP_MAC_ADMIN)) @@ -1782,21 +1794,31 @@ static ssize_t smk_write_unconfined(struct file *file, const char __user *buf, if (data == NULL) return -ENOMEM; + if (copy_from_user(data, buf, count) != 0) { + rc = -EFAULT; + goto freeout; + } + /* - * Should the null string be passed in unset the unconfined value. - * This seems like something to be careful with as usually - * smk_import only expects to return NULL for errors. It - * is usually the case that a nullstring or "\n" would be - * bad to pass to smk_import but in fact this is useful here. + * Clear the smack_unconfined on invalid label errors. This means + * that we can pass a null string to unset the unconfined value. * - * smk_import will also reject a label beginning with '-', + * Importing will also reject a label beginning with '-', * so "-confine" will also work. + * + * But do so only on invalid label, not on system errors. */ - if (copy_from_user(data, buf, count) != 0) - rc = -EFAULT; - else - smack_unconfined = smk_import_entry(data, count); + skp = smk_import_entry(data, count); + if (PTR_ERR(skp) == -EINVAL) + skp = NULL; + else if (IS_ERR(skp)) { + rc = PTR_ERR(skp); + goto freeout; + } + + smack_unconfined = skp; +freeout: kfree(data); return rc; } @@ -1980,7 +2002,7 @@ static ssize_t smk_user_access(struct file *file, const char __user *buf, res = smk_access(rule.smk_subject, rule.smk_object, rule.smk_access1, NULL); else if (res != -ENOENT) - return -EINVAL; + return res; /* * smk_access() can return a value > 0 in the "bringup" case. @@ -2209,8 +2231,8 @@ static ssize_t smk_write_revoke_subj(struct file *file, const char __user *buf, } cp = smk_parse_smack(data, count); - if (cp == NULL) { - rc = -EINVAL; + if (IS_ERR(cp)) { + rc = PTR_ERR(cp); goto free_out; } @@ -2341,10 +2363,10 @@ static ssize_t smk_write_syslog(struct file *file, const char __user *buf, rc = -EFAULT; else { skp = smk_import_entry(data, count); - if (skp == NULL) - rc = -EINVAL; + if (IS_ERR(skp)) + rc = PTR_ERR(skp); else - smack_syslog_label = smk_import_entry(data, count); + smack_syslog_label = skp; } kfree(data); |