fix(bl1): invalidate SP in data cache during secure SMC
Invalidate the SP holding `smc_ctx_t` prior to enabling the data cache
when handling SMCs from the secure world. Enabling the data cache
without doing so results in dirty data either being evicted into main
memory, or being used directly from bl1. This corrupted data causes
system failure as the SMC handler attempts to use it.
Change-Id: I5b7225a6fdd1fcfe34ee054ca46dffea06b84b7d
Signed-off-by: Harrison Mutai <harrison.mutai@arm.com>
diff --git a/bl1/aarch32/bl1_exceptions.S b/bl1/aarch32/bl1_exceptions.S
index 493d2ca..4a6815f 100644
--- a/bl1/aarch32/bl1_exceptions.S
+++ b/bl1/aarch32/bl1_exceptions.S
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2016-2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2022, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
@@ -118,6 +118,14 @@
mov r0, #DISABLE_DCACHE
bl enable_mmu_svc_mon
+ /*
+ * Invalidate `smc_ctx_t` in data cache to prevent dirty data being
+ * used.
+ */
+ mov r0, r6
+ mov r1, #SMC_CTX_SIZE
+ bl inv_dcache_range
+
/* Enable the data cache. */
ldcopr r9, SCTLR
orr r9, r9, #SCTLR_C_BIT