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, 34 insertions, 0 deletions

diff --git a/include/soc/qcom/ice.h b/include/soc/qcom/ice.h
new file mode 100644
index 000000000..4bee553f0
--- /dev/null
+++ b/include/soc/qcom/ice.h
@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2023, Linaro Limited
+ */
+
+#ifndef __QCOM_ICE_H__
+#define __QCOM_ICE_H__
+
+#include <linux/blk-crypto.h>
+#include <linux/types.h>
+
+struct qcom_ice;
+
+int qcom_ice_enable(struct qcom_ice *ice);
+int qcom_ice_resume(struct qcom_ice *ice);
+int qcom_ice_suspend(struct qcom_ice *ice);
+int qcom_ice_program_key(struct qcom_ice *ice, unsigned int slot,
+			 const struct blk_crypto_key *blk_key);
+int qcom_ice_evict_key(struct qcom_ice *ice, int slot);
+enum blk_crypto_key_type qcom_ice_get_supported_key_type(struct qcom_ice *ice);
+int qcom_ice_derive_sw_secret(struct qcom_ice *ice,
+			      const u8 *eph_key, size_t eph_key_size,
+			      u8 sw_secret[BLK_CRYPTO_SW_SECRET_SIZE]);
+int qcom_ice_generate_key(struct qcom_ice *ice,
+			  u8 lt_key[BLK_CRYPTO_MAX_HW_WRAPPED_KEY_SIZE]);
+int qcom_ice_prepare_key(struct qcom_ice *ice,
+			 const u8 *lt_key, size_t lt_key_size,
+			 u8 eph_key[BLK_CRYPTO_MAX_HW_WRAPPED_KEY_SIZE]);
+int qcom_ice_import_key(struct qcom_ice *ice,
+			const u8 *raw_key, size_t raw_key_size,
+			u8 lt_key[BLK_CRYPTO_MAX_HW_WRAPPED_KEY_SIZE]);
+struct qcom_ice *devm_of_qcom_ice_get(struct device *dev);
+
+#endif /* __QCOM_ICE_H__ */