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, 33 insertions, 0 deletions

diff --git a/drivers/crypto/caam/Makefile b/drivers/crypto/caam/Makefile
new file mode 100644
index 000000000..d2eaf5205
--- /dev/null
+++ b/drivers/crypto/caam/Makefile
@@ -0,0 +1,33 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for the CAAM backend and dependent components
+#
+ifeq ($(CONFIG_CRYPTO_DEV_FSL_CAAM_DEBUG), y)
+	ccflags-y := -DDEBUG
+endif
+
+ccflags-y += -DVERSION=\"\"
+
+obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM_COMMON) += error.o
+obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM) += caam.o
+obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM_JR) += caam_jr.o
+obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM_CRYPTO_API_DESC) += caamalg_desc.o
+obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM_AHASH_API_DESC) += caamhash_desc.o
+
+caam-y := ctrl.o
+caam_jr-y := jr.o key_gen.o
+caam_jr-$(CONFIG_CRYPTO_DEV_FSL_CAAM_CRYPTO_API) += caamalg.o
+caam_jr-$(CONFIG_CRYPTO_DEV_FSL_CAAM_CRYPTO_API_QI) += caamalg_qi.o
+caam_jr-$(CONFIG_CRYPTO_DEV_FSL_CAAM_AHASH_API) += caamhash.o
+caam_jr-$(CONFIG_CRYPTO_DEV_FSL_CAAM_RNG_API) += caamrng.o
+caam_jr-$(CONFIG_CRYPTO_DEV_FSL_CAAM_PRNG_API) += caamprng.o
+caam_jr-$(CONFIG_CRYPTO_DEV_FSL_CAAM_PKC_API) += caampkc.o pkc_desc.o
+caam_jr-$(CONFIG_CRYPTO_DEV_FSL_CAAM_BLOB_GEN) += blob_gen.o
+
+caam-$(CONFIG_CRYPTO_DEV_FSL_CAAM_CRYPTO_API_QI) += qi.o
+caam-$(CONFIG_DEBUG_FS) += debugfs.o
+
+obj-$(CONFIG_CRYPTO_DEV_FSL_DPAA2_CAAM) += dpaa2_caam.o
+
+dpaa2_caam-y    := caamalg_qi2.o dpseci.o
+dpaa2_caam-$(CONFIG_DEBUG_FS) += dpseci-debugfs.o