Merge tag 'audit-pr-20190702' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit

Pull audit updates from Paul Moore:
 "This pull request is a bit early, but with some vacation time coming
  up I wanted to send this out now just in case the remote Internet Gods
  decide not to smile on me once the merge window opens. The patchset
  for v5.3 is pretty minor this time, the highlights include:

   - When the audit daemon is sent a signal, ensure we deliver
     information about the sender even when syscall auditing is not
     enabled/supported.

   - Add the ability to filter audit records based on network address
     family.

   - Tighten the audit field filtering restrictions on string based
     fields.

   - Cleanup the audit field filtering verification code.

   - Remove a few BUG() calls from the audit code"

* tag 'audit-pr-20190702' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
  audit: remove the BUG() calls in the audit rule comparison functions
  audit: enforce op for string fields
  audit: add saddr_fam filter field
  audit: re-structure audit field valid checks
  audit: deliver signal_info regarless of syscall

1 files changed, 38 insertions, 24 deletions

diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index 9f8e190e3bea..b0126e9c0743 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -322,7 +322,7 @@ static u32 audit_to_op(u32 op)
 /* check if an audit field is valid */
 static int audit_field_valid(struct audit_entry *entry, struct audit_field *f)
 {
-	switch(f->type) {
+	switch (f->type) {
 	case AUDIT_MSGTYPE:
 		if (entry->rule.listnr != AUDIT_FILTER_EXCLUDE &&
 		    entry->rule.listnr != AUDIT_FILTER_USER)
@@ -334,7 +334,7 @@ static int audit_field_valid(struct audit_entry *entry, struct audit_field *f)
 		break;
 	}
 
-	switch(entry->rule.listnr) {
+	switch (entry->rule.listnr) {
 	case AUDIT_FILTER_FS:
 		switch(f->type) {
 		case AUDIT_FSTYPE:
@@ -345,9 +345,16 @@ static int audit_field_valid(struct audit_entry *entry, struct audit_field *f)
 		}
 	}
 
-	switch(f->type) {
-	default:
-		return -EINVAL;
+	/* Check for valid field type and op */
+	switch (f->type) {
+	case AUDIT_ARG0:
+	case AUDIT_ARG1:
+	case AUDIT_ARG2:
+	case AUDIT_ARG3:
+	case AUDIT_PERS: /* <uapi/linux/personality.h> */
+	case AUDIT_DEVMINOR:
+		/* all ops are valid */
+		break;
 	case AUDIT_UID:
 	case AUDIT_EUID:
 	case AUDIT_SUID:
@@ -360,46 +367,53 @@ static int audit_field_valid(struct audit_entry *entry, struct audit_field *f)
 	case AUDIT_FSGID:
 	case AUDIT_OBJ_GID:
 	case AUDIT_PID:
-	case AUDIT_PERS:
 	case AUDIT_MSGTYPE:
 	case AUDIT_PPID:
 	case AUDIT_DEVMAJOR:
-	case AUDIT_DEVMINOR:
 	case AUDIT_EXIT:
 	case AUDIT_SUCCESS:
 	case AUDIT_INODE:
 	case AUDIT_SESSIONID:
+	case AUDIT_SUBJ_SEN:
+	case AUDIT_SUBJ_CLR:
+	case AUDIT_OBJ_LEV_LOW:
+	case AUDIT_OBJ_LEV_HIGH:
+	case AUDIT_SADDR_FAM:
 		/* bit ops are only useful on syscall args */
 		if (f->op == Audit_bitmask || f->op == Audit_bittest)
 			return -EINVAL;
 		break;
-	case AUDIT_ARG0:
-	case AUDIT_ARG1:
-	case AUDIT_ARG2:
-	case AUDIT_ARG3:
 	case AUDIT_SUBJ_USER:
 	case AUDIT_SUBJ_ROLE:
 	case AUDIT_SUBJ_TYPE:
-	case AUDIT_SUBJ_SEN:
-	case AUDIT_SUBJ_CLR:
 	case AUDIT_OBJ_USER:
 	case AUDIT_OBJ_ROLE:
 	case AUDIT_OBJ_TYPE:
-	case AUDIT_OBJ_LEV_LOW:
-	case AUDIT_OBJ_LEV_HIGH:
 	case AUDIT_WATCH:
 	case AUDIT_DIR:
 	case AUDIT_FILTERKEY:
-		break;
 	case AUDIT_LOGINUID_SET:
-		if ((f->val != 0) && (f->val != 1))
-			return -EINVAL;
-	/* FALL THROUGH */
 	case AUDIT_ARCH:
 	case AUDIT_FSTYPE:
+	case AUDIT_PERM:
+	case AUDIT_FILETYPE:
+	case AUDIT_FIELD_COMPARE:
+	case AUDIT_EXE:
+		/* only equal and not equal valid ops */
 		if (f->op != Audit_not_equal && f->op != Audit_equal)
 			return -EINVAL;
 		break;
+	default:
+		/* field not recognized */
+		return -EINVAL;
+	}
+
+	/* Check for select valid field values */
+	switch (f->type) {
+	case AUDIT_LOGINUID_SET:
+		if ((f->val != 0) && (f->val != 1))
+			return -EINVAL;
+		break;
 	case AUDIT_PERM:
 		if (f->val & ~15)
 			return -EINVAL;
@@ -412,11 +426,14 @@ static int audit_field_valid(struct audit_entry *entry, struct audit_field *f)
 		if (f->val > AUDIT_MAX_FIELD_COMPARE)
 			return -EINVAL;
 		break;
-	case AUDIT_EXE:
-		if (f->op != Audit_not_equal && f->op != Audit_equal)
+	case AUDIT_SADDR_FAM:
+		if (f->val >= AF_MAX)
 			return -EINVAL;
 		break;
+	default:
+		break;
 	}
+
 	return 0;
 }
 
@@ -1190,7 +1207,6 @@ int audit_comparator(u32 left, u32 op, u32 right)
 	case Audit_bittest:
 		return ((left & right) == right);
 	default:
-		BUG();
 		return 0;
 	}
 }
@@ -1213,7 +1229,6 @@ int audit_uid_comparator(kuid_t left, u32 op, kuid_t right)
 	case Audit_bitmask:
 	case Audit_bittest:
 	default:
-		BUG();
 		return 0;
 	}
 }
@@ -1236,7 +1251,6 @@ int audit_gid_comparator(kgid_t left, u32 op, kgid_t right)
 	case Audit_bitmask:
 	case Audit_bittest:
 	default:
-		BUG();
 		return 0;
 	}
 }