fix(security): workaround for CVE-2022-23960
Implements the loop workaround for Cortex-A77, Cortex-A78,
Cortex-A710, Cortex-X2, Neoverse N1, Neoverse N2 and Neoverse V1
CPUs.
Signed-off-by: Bipin Ravi <bipin.ravi@arm.com>
Change-Id: I11d342df7a2068a15e18f4974c645af3b341235b
diff --git a/lib/cpus/aarch64/neoverse_n2.S b/lib/cpus/aarch64/neoverse_n2.S
index 621aded..b93f2a6 100644
--- a/lib/cpus/aarch64/neoverse_n2.S
+++ b/lib/cpus/aarch64/neoverse_n2.S
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2020-2021, Arm Limited. All rights reserved.
+ * Copyright (c) 2020-2022, Arm Limited. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
@@ -8,6 +8,7 @@
#include <asm_macros.S>
#include <cpu_macros.S>
#include <neoverse_n2.h>
+#include "wa_cve_2022_23960_bhb_vector.S"
/* Hardware handled coherency */
#if HW_ASSISTED_COHERENCY == 0
@@ -19,6 +20,10 @@
#error "Neoverse-N2 supports only AArch64. Compile with CTX_INCLUDE_AARCH32_REGS=0"
#endif
+#if WORKAROUND_CVE_2022_23960
+ wa_cve_2022_23960_bhb_vector_table NEOVERSE_N2_BHB_LOOP_COUNT, neoverse_n2
+#endif /* WORKAROUND_CVE_2022_23960 */
+
/* --------------------------------------------------
* Errata Workaround for Neoverse N2 Erratum 2002655.
* This applies to revision r0p0 of Neoverse N2. it is still open.
@@ -333,6 +338,15 @@
b cpu_rev_var_ls
endfunc check_errata_2280757
+func check_errata_cve_2022_23960
+#if WORKAROUND_CVE_2022_23960
+ mov x0, #ERRATA_APPLIES
+#else
+ mov x0, #ERRATA_MISSING
+#endif
+ ret
+endfunc check_errata_cve_2022_23960
+
/* -------------------------------------------
* The CPU Ops reset function for Neoverse N2.
* -------------------------------------------
@@ -428,6 +442,15 @@
bl errata_n2_2002655_wa
#endif
+#if IMAGE_BL31 && WORKAROUND_CVE_2022_23960
+ /*
+ * The Neoverse-N2 generic vectors are overridden to apply errata
+ * mitigation on exception entry from lower ELs.
+ */
+ adr x0, wa_cve_vbar_neoverse_n2
+ msr vbar_el3, x0
+#endif /* IMAGE_BL31 && WORKAROUND_CVE_2022_23960 */
+
isb
ret x19
endfunc neoverse_n2_reset_func
@@ -469,6 +492,7 @@
report_errata ERRATA_N2_2138958, neoverse_n2, 2138958
report_errata ERRATA_N2_2242400, neoverse_n2, 2242400
report_errata ERRATA_N2_2280757, neoverse_n2, 2280757
+ report_errata WORKAROUND_CVE_2022_23960, neoverse_n2, cve_2022_23960
ldp x8, x30, [sp], #16
ret