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, 37 insertions, 0 deletions

diff --git a/drivers/pinctrl/freescale/Makefile b/drivers/pinctrl/freescale/Makefile
new file mode 100644
index 000000000..d27085c2b
--- /dev/null
+++ b/drivers/pinctrl/freescale/Makefile
@@ -0,0 +1,37 @@
+# SPDX-License-Identifier: GPL-2.0
+# Freescale pin control drivers
+obj-$(CONFIG_PINCTRL_IMX)	+= pinctrl-imx.o
+obj-$(CONFIG_PINCTRL_IMX_SCU)	+= pinctrl-scu.o
+obj-$(CONFIG_PINCTRL_IMX_SCMI)	+= pinctrl-imx-scmi.o
+obj-$(CONFIG_PINCTRL_IMX1_CORE)	+= pinctrl-imx1-core.o
+obj-$(CONFIG_PINCTRL_IMX1)	+= pinctrl-imx1.o
+obj-$(CONFIG_PINCTRL_IMX27)	+= pinctrl-imx27.o
+obj-$(CONFIG_PINCTRL_IMX35)	+= pinctrl-imx35.o
+obj-$(CONFIG_PINCTRL_IMX50)	+= pinctrl-imx50.o
+obj-$(CONFIG_PINCTRL_IMX51)	+= pinctrl-imx51.o
+obj-$(CONFIG_PINCTRL_IMX53)	+= pinctrl-imx53.o
+obj-$(CONFIG_PINCTRL_IMX6Q)	+= pinctrl-imx6q.o
+obj-$(CONFIG_PINCTRL_IMX6Q)	+= pinctrl-imx6dl.o
+obj-$(CONFIG_PINCTRL_IMX6SL)	+= pinctrl-imx6sl.o
+obj-$(CONFIG_PINCTRL_IMX6SLL)	+= pinctrl-imx6sll.o
+obj-$(CONFIG_PINCTRL_IMX6SX)	+= pinctrl-imx6sx.o
+obj-$(CONFIG_PINCTRL_IMX6UL)	+= pinctrl-imx6ul.o
+obj-$(CONFIG_PINCTRL_IMX7D)	+= pinctrl-imx7d.o
+obj-$(CONFIG_PINCTRL_IMX7ULP)	+= pinctrl-imx7ulp.o
+obj-$(CONFIG_PINCTRL_IMX8MM)	+= pinctrl-imx8mm.o
+obj-$(CONFIG_PINCTRL_IMX8MN)	+= pinctrl-imx8mn.o
+obj-$(CONFIG_PINCTRL_IMX8MP)	+= pinctrl-imx8mp.o
+obj-$(CONFIG_PINCTRL_IMX8MQ)	+= pinctrl-imx8mq.o
+obj-$(CONFIG_PINCTRL_IMX8QM)	+= pinctrl-imx8qm.o
+obj-$(CONFIG_PINCTRL_IMX8QXP)	+= pinctrl-imx8qxp.o
+obj-$(CONFIG_PINCTRL_IMX8DXL)	+= pinctrl-imx8dxl.o
+obj-$(CONFIG_PINCTRL_IMX8ULP)	+= pinctrl-imx8ulp.o
+obj-$(CONFIG_PINCTRL_IMX91)	+= pinctrl-imx91.o
+obj-$(CONFIG_PINCTRL_IMX93)	+= pinctrl-imx93.o
+obj-$(CONFIG_PINCTRL_VF610)	+= pinctrl-vf610.o
+obj-$(CONFIG_PINCTRL_MXS)	+= pinctrl-mxs.o
+obj-$(CONFIG_PINCTRL_IMX23)	+= pinctrl-imx23.o
+obj-$(CONFIG_PINCTRL_IMX25)	+= pinctrl-imx25.o
+obj-$(CONFIG_PINCTRL_IMX28)	+= pinctrl-imx28.o
+obj-$(CONFIG_PINCTRL_IMXRT1050)	+= pinctrl-imxrt1050.o
+obj-$(CONFIG_PINCTRL_IMXRT1170)	+= pinctrl-imxrt1170.o