openrisc: fix arbitrary kernel memory access via or1k_atomic syscallgrafted

sys_or1k_atomic() (syscall 244 in the "or1k" ABI) takes two user
pointers, v1 and v2, and swaps the words they point to in hand-written
assembly.

    l.lwz   r29,0(r4)
    l.lwz   r27,0(r5)
    l.sw    0(r4),r27
    l.sw    0(r5),r29

The pointers are not checked with access_ok(). The four memory
accesses also have no exception table entries.

A caller passes a kernel address as either pointer, and the syscall
reads from and writes to it directly.

This gives an unprivileged process a kernel read/write primitive. It
overwrites kernel data such as the sys_call_table, gaining code
execution in kernel context.

Check both pointers before entering the critical section. Add fixups
for the four memory accesses so faults on valid but unmapped user
addresses return -EFAULT.

[shorne@gmail.com: fix comment style]
Fixes: 9d02a4283e9c ("OpenRISC: Boot code")
Cc: stable@vger.kernel.org
Signed-off-by: Ali Ahmet Memis <ali@iusegentoo.com>
Signed-off-by: Stafford Horne <shorne@gmail.com>

1 files changed, 68 insertions, 0 deletions

diff --git a/include/net/tls_prot.h b/include/net/tls_prot.h
new file mode 100644
index 000000000..68a407564
--- /dev/null
+++ b/include/net/tls_prot.h
@@ -0,0 +1,68 @@
+/* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */
+/*
+ * Copyright (c) 2023, Oracle and/or its affiliates.
+ *
+ * TLS Protocol definitions
+ *
+ * From https://www.iana.org/assignments/tls-parameters/tls-parameters.xhtml
+ */
+
+#ifndef _TLS_PROT_H
+#define _TLS_PROT_H
+
+/*
+ * TLS Record protocol: ContentType
+ */
+enum {
+	TLS_RECORD_TYPE_CHANGE_CIPHER_SPEC = 20,
+	TLS_RECORD_TYPE_ALERT = 21,
+	TLS_RECORD_TYPE_HANDSHAKE = 22,
+	TLS_RECORD_TYPE_DATA = 23,
+	TLS_RECORD_TYPE_HEARTBEAT = 24,
+	TLS_RECORD_TYPE_TLS12_CID = 25,
+	TLS_RECORD_TYPE_ACK = 26,
+};
+
+/*
+ * TLS Alert protocol: AlertLevel
+ */
+enum {
+	TLS_ALERT_LEVEL_WARNING = 1,
+	TLS_ALERT_LEVEL_FATAL = 2,
+};
+
+/*
+ * TLS Alert protocol: AlertDescription
+ */
+enum {
+	TLS_ALERT_DESC_CLOSE_NOTIFY = 0,
+	TLS_ALERT_DESC_UNEXPECTED_MESSAGE = 10,
+	TLS_ALERT_DESC_BAD_RECORD_MAC = 20,
+	TLS_ALERT_DESC_RECORD_OVERFLOW = 22,
+	TLS_ALERT_DESC_HANDSHAKE_FAILURE = 40,
+	TLS_ALERT_DESC_BAD_CERTIFICATE = 42,
+	TLS_ALERT_DESC_UNSUPPORTED_CERTIFICATE = 43,
+	TLS_ALERT_DESC_CERTIFICATE_REVOKED = 44,
+	TLS_ALERT_DESC_CERTIFICATE_EXPIRED = 45,
+	TLS_ALERT_DESC_CERTIFICATE_UNKNOWN = 46,
+	TLS_ALERT_DESC_ILLEGAL_PARAMETER = 47,
+	TLS_ALERT_DESC_UNKNOWN_CA = 48,
+	TLS_ALERT_DESC_ACCESS_DENIED = 49,
+	TLS_ALERT_DESC_DECODE_ERROR = 50,
+	TLS_ALERT_DESC_DECRYPT_ERROR = 51,
+	TLS_ALERT_DESC_TOO_MANY_CIDS_REQUESTED	= 52,
+	TLS_ALERT_DESC_PROTOCOL_VERSION = 70,
+	TLS_ALERT_DESC_INSUFFICIENT_SECURITY = 71,
+	TLS_ALERT_DESC_INTERNAL_ERROR = 80,
+	TLS_ALERT_DESC_INAPPROPRIATE_FALLBACK = 86,
+	TLS_ALERT_DESC_USER_CANCELED = 90,
+	TLS_ALERT_DESC_MISSING_EXTENSION = 109,
+	TLS_ALERT_DESC_UNSUPPORTED_EXTENSION = 110,
+	TLS_ALERT_DESC_UNRECOGNIZED_NAME = 112,
+	TLS_ALERT_DESC_BAD_CERTIFICATE_STATUS_RESPONSE = 113,
+	TLS_ALERT_DESC_UNKNOWN_PSK_IDENTITY = 115,
+	TLS_ALERT_DESC_CERTIFICATE_REQUIRED = 116,
+	TLS_ALERT_DESC_NO_APPLICATION_PROTOCOL = 120,
+};
+
+#endif /* _TLS_PROT_H */