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, 90 insertions, 0 deletions

diff --git a/include/uapi/sound/hdsp.h b/include/uapi/sound/hdsp.h
new file mode 100644
index 000000000..096195465
--- /dev/null
+++ b/include/uapi/sound/hdsp.h
@@ -0,0 +1,90 @@
+/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
+#ifndef __SOUND_HDSP_H
+#define __SOUND_HDSP_H
+
+/*
+ *   Copyright (C) 2003 Thomas Charbonnel (thomas@undata.org)
+ */
+
+#ifdef __linux__
+#include <linux/types.h>
+#endif
+
+#define HDSP_MATRIX_MIXER_SIZE 2048
+
+enum HDSP_IO_Type {
+	Digiface,
+	Multiface,
+	H9652,
+	H9632,
+	RPM,
+	Undefined,
+};
+
+struct hdsp_peak_rms {
+	__u32 input_peaks[26];
+	__u32 playback_peaks[26];
+	__u32 output_peaks[28];
+	__u64 input_rms[26];
+	__u64 playback_rms[26];
+	/* These are only used for H96xx cards */
+	__u64 output_rms[26];
+};
+
+#define SNDRV_HDSP_IOCTL_GET_PEAK_RMS _IOR('H', 0x40, struct hdsp_peak_rms)
+
+struct hdsp_config_info {
+	unsigned char pref_sync_ref;
+	unsigned char wordclock_sync_check;
+	unsigned char spdif_sync_check;
+	unsigned char adatsync_sync_check;
+	unsigned char adat_sync_check[3];
+	unsigned char spdif_in;
+	unsigned char spdif_out;
+	unsigned char spdif_professional;
+	unsigned char spdif_emphasis;
+	unsigned char spdif_nonaudio;
+	unsigned int spdif_sample_rate;
+	unsigned int system_sample_rate;
+	unsigned int autosync_sample_rate;
+	unsigned char system_clock_mode;
+	unsigned char clock_source;
+	unsigned char autosync_ref;
+	unsigned char line_out;
+	unsigned char passthru; 
+	unsigned char da_gain;
+	unsigned char ad_gain;
+	unsigned char phone_gain;
+	unsigned char xlr_breakout_cable;
+	unsigned char analog_extension_board;
+};
+
+#define SNDRV_HDSP_IOCTL_GET_CONFIG_INFO _IOR('H', 0x41, struct hdsp_config_info)
+
+struct hdsp_firmware {
+	void *firmware_data;	/* 24413 x 4 bytes */
+};
+
+#define SNDRV_HDSP_IOCTL_UPLOAD_FIRMWARE _IOW('H', 0x42, struct hdsp_firmware)
+
+struct hdsp_version {
+	enum HDSP_IO_Type io_type;
+	unsigned short firmware_rev;
+};
+
+#define SNDRV_HDSP_IOCTL_GET_VERSION _IOR('H', 0x43, struct hdsp_version)
+
+struct hdsp_mixer {
+	unsigned short matrix[HDSP_MATRIX_MIXER_SIZE];
+};
+
+#define SNDRV_HDSP_IOCTL_GET_MIXER _IOR('H', 0x44, struct hdsp_mixer)
+
+struct hdsp_9632_aeb {
+	int aebi;
+	int aebo;
+};
+
+#define SNDRV_HDSP_IOCTL_GET_9632_AEB _IOR('H', 0x45, struct hdsp_9632_aeb)
+
+#endif /* __SOUND_HDSP_H */