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, 109 insertions, 0 deletions

diff --git a/Documentation/ABI/testing/debugfs-driver-qat b/Documentation/ABI/testing/debugfs-driver-qat
new file mode 100644
index 000000000..3f1efbbad
--- /dev/null
+++ b/Documentation/ABI/testing/debugfs-driver-qat
@@ -0,0 +1,109 @@
+What:		/sys/kernel/debug/qat_<device>_<BDF>/fw_counters
+Date:		November 2023
+KernelVersion:	6.6
+Contact:	qat-linux@intel.com
+Description:	(RO) Read returns the number of requests sent to the FW and the number of responses
+		received from the FW for each Acceleration Engine
+		Reported firmware counters::
+
+			<N>: Number of requests sent from Acceleration Engine N to FW and responses
+			     Acceleration Engine N received from FW
+
+What:		/sys/kernel/debug/qat_<device>_<BDF>/heartbeat/config
+Date:		November 2023
+KernelVersion:	6.6
+Contact:	qat-linux@intel.com
+Description:	(RW) Read returns value of the Heartbeat update period.
+		Write to the file changes this period value.
+
+		This period should reflect planned polling interval of device
+		health status. High frequency Heartbeat monitoring wastes CPU cycles
+		but minimizes the customer’s system downtime. Also, if there are
+		large service requests that take some time to complete, high frequency
+		Heartbeat monitoring could result in false reports of unresponsiveness
+		and in those cases, period needs to be increased.
+
+		This parameter is effective only for c3xxx, c62x, dh895xcc devices.
+		4xxx has this value internally fixed to 200ms.
+
+		Default value is set to 500. Minimal allowed value is 200.
+		All values are expressed in milliseconds.
+
+What:		/sys/kernel/debug/qat_<device>_<BDF>/heartbeat/queries_failed
+Date:		November 2023
+KernelVersion:	6.6
+Contact:	qat-linux@intel.com
+Description:	(RO) Read returns the number of times the device became unresponsive.
+
+		Attribute returns value of the counter which is incremented when
+		status query results negative.
+
+What:		/sys/kernel/debug/qat_<device>_<BDF>/heartbeat/queries_sent
+Date:		November 2023
+KernelVersion:	6.6
+Contact:	qat-linux@intel.com
+Description:	(RO) Read returns the number of times the control process checked
+		if the device is responsive.
+
+		Attribute returns value of the counter which is incremented on
+		every status query.
+
+What:		/sys/kernel/debug/qat_<device>_<BDF>/heartbeat/status
+Date:		November 2023
+KernelVersion:	6.6
+Contact:	qat-linux@intel.com
+Description:	(RO) Read returns the device health status.
+
+		Returns 0 when device is healthy or -1 when is unresponsive
+		or the query failed to send.
+
+		The driver does not monitor for Heartbeat. It is left for a user
+		to poll the status periodically.
+
+What:		/sys/kernel/debug/qat_<device>_<BDF>/pm_status
+Date:		January 2024
+KernelVersion:	6.7
+Contact:	qat-linux@intel.com
+Description:	(RO) Read returns power management information specific to the
+		QAT device.
+
+		This attribute is only available for qat_4xxx and qat_6xxx devices.
+
+What:		/sys/kernel/debug/qat_<device>_<BDF>/cnv_errors
+Date:		January 2024
+KernelVersion:	6.7
+Contact:	qat-linux@intel.com
+Description:	(RO) Read returns, for each Acceleration Engine (AE), the number
+		of errors and the type of the last error detected by the device
+		when performing verified compression.
+		Reported counters::
+
+			<N>: Number of Compress and Verify (CnV) errors and type
+			     of the last CnV error detected by Acceleration
+			     Engine N.
+
+What:		/sys/kernel/debug/qat_<device>_<BDF>/heartbeat/inject_error
+Date:		March 2024
+KernelVersion:	6.8
+Contact:	qat-linux@intel.com
+Description:	(WO) Write to inject an error that simulates an heartbeat
+		failure. This is to be used for testing purposes.
+
+		After writing this file, the driver stops arbitration on a
+		random engine and disables the fetching of heartbeat counters.
+		If a workload is running on the device, a job submitted to the
+		accelerator might not get a response and a read of the
+		`heartbeat/status` attribute might report -1, i.e. device
+		unresponsive.
+		The error is unrecoverable thus the device must be restarted to
+		restore its functionality.
+
+		This attribute is available only when the kernel is built with
+		CONFIG_CRYPTO_DEV_QAT_ERROR_INJECTION=y.
+
+		A write of 1 enables error injection.
+
+		The following example shows how to enable error injection::
+
+			# cd /sys/kernel/debug/qat_<device>_<BDF>
+			# echo 1 > heartbeat/inject_error