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, 14 insertions, 0 deletions

diff --git a/drivers/pinctrl/stm32/Makefile b/drivers/pinctrl/stm32/Makefile
new file mode 100644
index 000000000..98a1bbc7e
--- /dev/null
+++ b/drivers/pinctrl/stm32/Makefile
@@ -0,0 +1,14 @@
+# SPDX-License-Identifier: GPL-2.0
+# Core
+obj-$(CONFIG_PINCTRL_STM32) += pinctrl-stm32.o
+
+# SoC Drivers
+obj-$(CONFIG_PINCTRL_STM32F429)	+= pinctrl-stm32f429.o
+obj-$(CONFIG_PINCTRL_STM32F469)	+= pinctrl-stm32f469.o
+obj-$(CONFIG_PINCTRL_STM32F746)	+= pinctrl-stm32f746.o
+obj-$(CONFIG_PINCTRL_STM32F769)	+= pinctrl-stm32f769.o
+obj-$(CONFIG_PINCTRL_STM32H743)	+= pinctrl-stm32h743.o
+obj-$(CONFIG_PINCTRL_STM32MP135) += pinctrl-stm32mp135.o
+obj-$(CONFIG_PINCTRL_STM32MP157) += pinctrl-stm32mp157.o
+obj-$(CONFIG_PINCTRL_STM32MP257) += pinctrl-stm32mp257.o
+obj-$(CONFIG_PINCTRL_STM32_HDP) += pinctrl-stm32-hdp.o