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, 36 insertions, 0 deletions

diff --git a/drivers/scsi/lpfc/Makefile b/drivers/scsi/lpfc/Makefile
new file mode 100644
index 000000000..bbd1faf41
--- /dev/null
+++ b/drivers/scsi/lpfc/Makefile
@@ -0,0 +1,36 @@
+#/*******************************************************************
+# * This file is part of the Emulex Linux Device Driver for         *
+# * Fibre Channel Host Bus Adapters.                                *
+# * Copyright (C) 2017-2018 Broadcom. All Rights Reserved. The term *
+# * “Broadcom” refers to Broadcom Inc. and/or its subsidiaries.     *
+# * Copyright (C) 2004-2012 Emulex.  All rights reserved.           *
+# * EMULEX and SLI are trademarks of Emulex.                        *
+# * www.broadcom.com                                                *
+# *                                                                 *
+# * This program is free software; you can redistribute it and/or   *
+# * modify it under the terms of version 2 of the GNU General       *
+# * Public License as published by the Free Software Foundation.    *
+# * This program is distributed in the hope that it will be useful. *
+# * ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND          *
+# * WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY,  *
+# * FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT, ARE      *
+# * DISCLAIMED, EXCEPT TO THE EXTENT THAT SUCH DISCLAIMERS ARE HELD *
+# * TO BE LEGALLY INVALID.  See the GNU General Public License for  *
+# * more details, a copy of which can be found in the file COPYING  *
+# * included with this package.                                     *
+# *******************************************************************/
+######################################################################
+
+ccflags-$(GCOV) := -fprofile-arcs -ftest-coverage
+ccflags-$(GCOV) += -O0
+
+ifdef WARNINGS_BECOME_ERRORS
+ccflags-y += -Werror
+endif
+
+obj-$(CONFIG_SCSI_LPFC) := lpfc.o
+
+lpfc-objs := lpfc_mem.o lpfc_sli.o lpfc_ct.o lpfc_els.o \
+	lpfc_hbadisc.o	lpfc_init.o lpfc_mbox.o lpfc_nportdisc.o   \
+	lpfc_scsi.o lpfc_attr.o lpfc_vport.o lpfc_debugfs.o lpfc_bsg.o \
+	lpfc_nvme.o lpfc_nvmet.o lpfc_vmid.o