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, 168 insertions, 0 deletions

diff --git a/include/trace/misc/rdma.h b/include/trace/misc/rdma.h
new file mode 100644
index 000000000..81bb454fc
--- /dev/null
+++ b/include/trace/misc/rdma.h
@@ -0,0 +1,168 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2017 Oracle.  All rights reserved.
+ */
+
+/*
+ * enum ib_event_type, from include/rdma/ib_verbs.h
+ */
+#define IB_EVENT_LIST				\
+	ib_event(CQ_ERR)			\
+	ib_event(QP_FATAL)			\
+	ib_event(QP_REQ_ERR)			\
+	ib_event(QP_ACCESS_ERR)			\
+	ib_event(COMM_EST)			\
+	ib_event(SQ_DRAINED)			\
+	ib_event(PATH_MIG)			\
+	ib_event(PATH_MIG_ERR)			\
+	ib_event(DEVICE_FATAL)			\
+	ib_event(PORT_ACTIVE)			\
+	ib_event(PORT_ERR)			\
+	ib_event(LID_CHANGE)			\
+	ib_event(PKEY_CHANGE)			\
+	ib_event(SM_CHANGE)			\
+	ib_event(SRQ_ERR)			\
+	ib_event(SRQ_LIMIT_REACHED)		\
+	ib_event(QP_LAST_WQE_REACHED)		\
+	ib_event(CLIENT_REREGISTER)		\
+	ib_event(GID_CHANGE)			\
+	ib_event_end(WQ_FATAL)
+
+#undef ib_event
+#undef ib_event_end
+
+#define ib_event(x)		TRACE_DEFINE_ENUM(IB_EVENT_##x);
+#define ib_event_end(x)		TRACE_DEFINE_ENUM(IB_EVENT_##x);
+
+IB_EVENT_LIST
+
+#undef ib_event
+#undef ib_event_end
+
+#define ib_event(x)		{ IB_EVENT_##x, #x },
+#define ib_event_end(x)		{ IB_EVENT_##x, #x }
+
+#define rdma_show_ib_event(x) \
+		__print_symbolic(x, IB_EVENT_LIST)
+
+/*
+ * enum ib_wc_status type, from include/rdma/ib_verbs.h
+ */
+#define IB_WC_STATUS_LIST			\
+	ib_wc_status(SUCCESS)			\
+	ib_wc_status(LOC_LEN_ERR)		\
+	ib_wc_status(LOC_QP_OP_ERR)		\
+	ib_wc_status(LOC_EEC_OP_ERR)		\
+	ib_wc_status(LOC_PROT_ERR)		\
+	ib_wc_status(WR_FLUSH_ERR)		\
+	ib_wc_status(MW_BIND_ERR)		\
+	ib_wc_status(BAD_RESP_ERR)		\
+	ib_wc_status(LOC_ACCESS_ERR)		\
+	ib_wc_status(REM_INV_REQ_ERR)		\
+	ib_wc_status(REM_ACCESS_ERR)		\
+	ib_wc_status(REM_OP_ERR)		\
+	ib_wc_status(RETRY_EXC_ERR)		\
+	ib_wc_status(RNR_RETRY_EXC_ERR)		\
+	ib_wc_status(LOC_RDD_VIOL_ERR)		\
+	ib_wc_status(REM_INV_RD_REQ_ERR)	\
+	ib_wc_status(REM_ABORT_ERR)		\
+	ib_wc_status(INV_EECN_ERR)		\
+	ib_wc_status(INV_EEC_STATE_ERR)		\
+	ib_wc_status(FATAL_ERR)			\
+	ib_wc_status(RESP_TIMEOUT_ERR)		\
+	ib_wc_status_end(GENERAL_ERR)
+
+#undef ib_wc_status
+#undef ib_wc_status_end
+
+#define ib_wc_status(x)		TRACE_DEFINE_ENUM(IB_WC_##x);
+#define ib_wc_status_end(x)	TRACE_DEFINE_ENUM(IB_WC_##x);
+
+IB_WC_STATUS_LIST
+
+#undef ib_wc_status
+#undef ib_wc_status_end
+
+#define ib_wc_status(x)		{ IB_WC_##x, #x },
+#define ib_wc_status_end(x)	{ IB_WC_##x, #x }
+
+#define rdma_show_wc_status(x) \
+		__print_symbolic(x, IB_WC_STATUS_LIST)
+
+/*
+ * enum ib_cm_event_type, from include/rdma/ib_cm.h
+ */
+#define IB_CM_EVENT_LIST			\
+	ib_cm_event(REQ_ERROR)			\
+	ib_cm_event(REQ_RECEIVED)		\
+	ib_cm_event(REP_ERROR)			\
+	ib_cm_event(REP_RECEIVED)		\
+	ib_cm_event(RTU_RECEIVED)		\
+	ib_cm_event(USER_ESTABLISHED)		\
+	ib_cm_event(DREQ_ERROR)			\
+	ib_cm_event(DREQ_RECEIVED)		\
+	ib_cm_event(DREP_RECEIVED)		\
+	ib_cm_event(TIMEWAIT_EXIT)		\
+	ib_cm_event(MRA_RECEIVED)		\
+	ib_cm_event(REJ_RECEIVED)		\
+	ib_cm_event(LAP_ERROR)			\
+	ib_cm_event(LAP_RECEIVED)		\
+	ib_cm_event(APR_RECEIVED)		\
+	ib_cm_event(SIDR_REQ_ERROR)		\
+	ib_cm_event(SIDR_REQ_RECEIVED)		\
+	ib_cm_event_end(SIDR_REP_RECEIVED)
+
+#undef ib_cm_event
+#undef ib_cm_event_end
+
+#define ib_cm_event(x)		TRACE_DEFINE_ENUM(IB_CM_##x);
+#define ib_cm_event_end(x)	TRACE_DEFINE_ENUM(IB_CM_##x);
+
+IB_CM_EVENT_LIST
+
+#undef ib_cm_event
+#undef ib_cm_event_end
+
+#define ib_cm_event(x)		{ IB_CM_##x, #x },
+#define ib_cm_event_end(x)	{ IB_CM_##x, #x }
+
+#define rdma_show_ib_cm_event(x) \
+		__print_symbolic(x, IB_CM_EVENT_LIST)
+
+/*
+ * enum rdma_cm_event_type, from include/rdma/rdma_cm.h
+ */
+#define RDMA_CM_EVENT_LIST			\
+	rdma_cm_event(ADDR_RESOLVED)		\
+	rdma_cm_event(ADDR_ERROR)		\
+	rdma_cm_event(ROUTE_RESOLVED)		\
+	rdma_cm_event(ROUTE_ERROR)		\
+	rdma_cm_event(CONNECT_REQUEST)		\
+	rdma_cm_event(CONNECT_RESPONSE)		\
+	rdma_cm_event(CONNECT_ERROR)		\
+	rdma_cm_event(UNREACHABLE)		\
+	rdma_cm_event(REJECTED)			\
+	rdma_cm_event(ESTABLISHED)		\
+	rdma_cm_event(DISCONNECTED)		\
+	rdma_cm_event(DEVICE_REMOVAL)		\
+	rdma_cm_event(MULTICAST_JOIN)		\
+	rdma_cm_event(MULTICAST_ERROR)		\
+	rdma_cm_event(ADDR_CHANGE)		\
+	rdma_cm_event_end(TIMEWAIT_EXIT)
+
+#undef rdma_cm_event
+#undef rdma_cm_event_end
+
+#define rdma_cm_event(x)	TRACE_DEFINE_ENUM(RDMA_CM_EVENT_##x);
+#define rdma_cm_event_end(x)	TRACE_DEFINE_ENUM(RDMA_CM_EVENT_##x);
+
+RDMA_CM_EVENT_LIST
+
+#undef rdma_cm_event
+#undef rdma_cm_event_end
+
+#define rdma_cm_event(x)	{ RDMA_CM_EVENT_##x, #x },
+#define rdma_cm_event_end(x)	{ RDMA_CM_EVENT_##x, #x }
+
+#define rdma_show_cm_event(x) \
+		__print_symbolic(x, RDMA_CM_EVENT_LIST)