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, 46 insertions, 0 deletions

diff --git a/include/sound/rt5682.h b/include/sound/rt5682.h
new file mode 100644
index 000000000..4256df721
--- /dev/null
+++ b/include/sound/rt5682.h
@@ -0,0 +1,46 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * linux/sound/rt5682.h -- Platform data for RT5682
+ *
+ * Copyright 2018 Realtek Microelectronics
+ */
+
+#ifndef __LINUX_SND_RT5682_H
+#define __LINUX_SND_RT5682_H
+
+enum rt5682_dmic1_data_pin {
+	RT5682_DMIC1_NULL,
+	RT5682_DMIC1_DATA_GPIO2,
+	RT5682_DMIC1_DATA_GPIO5,
+};
+
+enum rt5682_dmic1_clk_pin {
+	RT5682_DMIC1_CLK_GPIO1,
+	RT5682_DMIC1_CLK_GPIO3,
+};
+
+enum rt5682_jd_src {
+	RT5682_JD_NULL,
+	RT5682_JD1,
+};
+
+enum rt5682_dai_clks {
+	RT5682_DAI_WCLK_IDX,
+	RT5682_DAI_BCLK_IDX,
+	RT5682_DAI_NUM_CLKS,
+};
+
+struct rt5682_platform_data {
+	enum rt5682_dmic1_data_pin dmic1_data_pin;
+	enum rt5682_dmic1_clk_pin dmic1_clk_pin;
+	enum rt5682_jd_src jd_src;
+	unsigned int btndet_delay;
+	unsigned int dmic_clk_rate;
+	unsigned int dmic_delay;
+	bool dmic_clk_driving_high;
+
+	const char *dai_clk_names[RT5682_DAI_NUM_CLKS];
+};
+
+#endif
+