1 files changed, 41 insertions, 14 deletions

diff --git a/security/apparmor/policy_unpack.c b/security/apparmor/policy_unpack.c
index f6c2bcb2ab14..8cfc9493eefc 100644
--- a/security/apparmor/policy_unpack.c
+++ b/security/apparmor/policy_unpack.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * AppArmor security module
  *
@@ -7,11 +8,6 @@
  * Copyright (C) 1998-2008 Novell/SUSE
  * Copyright 2009-2010 Canonical Ltd.
  *
- * 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, version 2 of the
- * License.
- *
  * AppArmor uses a serialized binary format for loading policy. To find
  * policy format documentation see Documentation/admin-guide/LSM/apparmor.rst
  * All policy is validated before it is used.
@@ -223,16 +219,21 @@ static void *kvmemdup(const void *src, size_t len)
 static size_t unpack_u16_chunk(struct aa_ext *e, char **chunk)
 {
 	size_t size = 0;
+	void *pos = e->pos;
 
 	if (!inbounds(e, sizeof(u16)))
-		return 0;
+		goto fail;
 	size = le16_to_cpu(get_unaligned((__le16 *) e->pos));
 	e->pos += sizeof(__le16);
 	if (!inbounds(e, size))
-		return 0;
+		goto fail;
 	*chunk = e->pos;
 	e->pos += size;
 	return size;
+
+fail:
+	e->pos = pos;
+	return 0;
 }
 
 /* unpack control byte */
@@ -276,7 +277,7 @@ static bool unpack_nameX(struct aa_ext *e, enum aa_code code, const char *name)
 		char *tag = NULL;
 		size_t size = unpack_u16_chunk(e, &tag);
 		/* if a name is specified it must match. otherwise skip tag */
-		if (name && (!size || strcmp(name, tag)))
+		if (name && (!size || tag[size-1] != '\0' || strcmp(name, tag)))
 			goto fail;
 	} else if (name) {
 		/* if a name is specified and there is no name tag fail */
@@ -294,62 +295,84 @@ fail:
 
 static bool unpack_u8(struct aa_ext *e, u8 *data, const char *name)
 {
+	void *pos = e->pos;
+
 	if (unpack_nameX(e, AA_U8, name)) {
 		if (!inbounds(e, sizeof(u8)))
-			return 0;
+			goto fail;
 		if (data)
 			*data = get_unaligned((u8 *)e->pos);
 		e->pos += sizeof(u8);
 		return 1;
 	}
+
+fail:
+	e->pos = pos;
 	return 0;
 }
 
 static bool unpack_u32(struct aa_ext *e, u32 *data, const char *name)
 {
+	void *pos = e->pos;
+
 	if (unpack_nameX(e, AA_U32, name)) {
 		if (!inbounds(e, sizeof(u32)))
-			return 0;
+			goto fail;
 		if (data)
 			*data = le32_to_cpu(get_unaligned((__le32 *) e->pos));
 		e->pos += sizeof(u32);
 		return 1;
 	}
+
+fail:
+	e->pos = pos;
 	return 0;
 }
 
 static bool unpack_u64(struct aa_ext *e, u64 *data, const char *name)
 {
+	void *pos = e->pos;
+
 	if (unpack_nameX(e, AA_U64, name)) {
 		if (!inbounds(e, sizeof(u64)))
-			return 0;
+			goto fail;
 		if (data)
 			*data = le64_to_cpu(get_unaligned((__le64 *) e->pos));
 		e->pos += sizeof(u64);
 		return 1;
 	}
+
+fail:
+	e->pos = pos;
 	return 0;
 }
 
 static size_t unpack_array(struct aa_ext *e, const char *name)
 {
+	void *pos = e->pos;
+
 	if (unpack_nameX(e, AA_ARRAY, name)) {
 		int size;
 		if (!inbounds(e, sizeof(u16)))
-			return 0;
+			goto fail;
 		size = (int)le16_to_cpu(get_unaligned((__le16 *) e->pos));
 		e->pos += sizeof(u16);
 		return size;
 	}
+
+fail:
+	e->pos = pos;
 	return 0;
 }
 
 static size_t unpack_blob(struct aa_ext *e, char **blob, const char *name)
 {
+	void *pos = e->pos;
+
 	if (unpack_nameX(e, AA_BLOB, name)) {
 		u32 size;
 		if (!inbounds(e, sizeof(u32)))
-			return 0;
+			goto fail;
 		size = le32_to_cpu(get_unaligned((__le32 *) e->pos));
 		e->pos += sizeof(u32);
 		if (inbounds(e, (size_t) size)) {
@@ -358,6 +381,9 @@ static size_t unpack_blob(struct aa_ext *e, char **blob, const char *name)
 			return size;
 		}
 	}
+
+fail:
+	e->pos = pos;
 	return 0;
 }
 
@@ -374,9 +400,10 @@ static int unpack_str(struct aa_ext *e, const char **string, const char *name)
 			if (src_str[size - 1] != 0)
 				goto fail;
 			*string = src_str;
+
+			return size;
 		}
 	}
-	return size;
 
 fail:
 	e->pos = pos;