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, 23 insertions, 0 deletions

diff --git a/drivers/net/ipa/Kconfig b/drivers/net/ipa/Kconfig
new file mode 100644
index 000000000..01d219d37
--- /dev/null
+++ b/drivers/net/ipa/Kconfig
@@ -0,0 +1,23 @@
+config QCOM_IPA
+	tristate "Qualcomm IPA support"
+	depends on NET && QCOM_SMEM
+	depends on ARCH_QCOM || COMPILE_TEST
+	depends on INTERCONNECT
+	depends on QCOM_RPROC_COMMON || (QCOM_RPROC_COMMON=n && COMPILE_TEST)
+	depends on QCOM_AOSS_QMP || QCOM_AOSS_QMP=n
+	select QCOM_MDT_LOADER
+	select QCOM_SCM
+	select QCOM_QMI_HELPERS
+	help
+	  Choose Y or M here to include support for the Qualcomm
+	  IP Accelerator (IPA), a hardware block present in some
+	  Qualcomm SoCs.  The IPA is a programmable protocol processor
+	  that is capable of generic hardware handling of IP packets,
+	  including routing, filtering, and NAT.  Currently the IPA
+	  driver supports only basic transport of network traffic
+	  between the AP and modem.
+
+	  Note that if selected, the selection type must match that
+	  of QCOM_Q6V5_COMMON (Y or M).
+
+	  If unsure, say N.