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-rw-r--r--arch/arm/include/asm/assembler.h4
-rw-r--r--arch/arm/lib/copy_from_user.S9
2 files changed, 13 insertions, 0 deletions
diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h
index 307901f88a1e..483481c6937e 100644
--- a/arch/arm/include/asm/assembler.h
+++ b/arch/arm/include/asm/assembler.h
@@ -454,6 +454,10 @@ THUMB( orr \reg , \reg , #PSR_T_BIT )
adds \tmp, \addr, #\size - 1
sbcccs \tmp, \tmp, \limit
bcs \bad
+#ifdef CONFIG_CPU_SPECTRE
+ movcs \addr, #0
+ csdb
+#endif
#endif
.endm
diff --git a/arch/arm/lib/copy_from_user.S b/arch/arm/lib/copy_from_user.S
index 1512bebfbf1b..d36329cefedc 100644
--- a/arch/arm/lib/copy_from_user.S
+++ b/arch/arm/lib/copy_from_user.S
@@ -90,6 +90,15 @@
.text
ENTRY(arm_copy_from_user)
+#ifdef CONFIG_CPU_SPECTRE
+ get_thread_info r3
+ ldr r3, [r3, #TI_ADDR_LIMIT]
+ adds ip, r1, r2 @ ip=addr+size
+ sub r3, r3, #1 @ addr_limit - 1
+ cmpcc ip, r3 @ if (addr+size > addr_limit - 1)
+ movcs r1, #0 @ addr = NULL
+ csdb
+#endif
#include "copy_template.S"