[PATCH v3 6/6] powerpc/fsl: Sanitize the syscall table for NXP PowerPC 32 bit platforms
From: Diana Craciun <hidden>
Date: 2018-07-13 13:52:30
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
Used barrier_nospec to sanitize the syscall table. Signed-off-by: Diana Craciun <redacted> --- History: v2-->v3 - included in the series arch/powerpc/kernel/entry_32.S | 10 ++++++++++ 1 file changed, 10 insertions(+)
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 973577f..8f05280 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S@@ -33,6 +33,7 @@ #include <asm/unistd.h> #include <asm/ptrace.h> #include <asm/export.h> +#include <asm/barrier.h> /* * MSR_KERNEL is > 0x10000 on 4xx/Book-E since it include MSR_CE.
@@ -358,6 +359,15 @@ syscall_dotrace_cont: ori r10,r10,sys_call_table@l slwi r0,r0,2 bge- 66f + + barrier_nospec_asm + /* + * Prevent the load of the handler below (based on the user-passed + * system call number) being speculatively executed until the test + * against NR_syscalls and branch to .66f above has + * committed. + */ + lwzx r10,r10,r0 /* Fetch system call handler [ptr] */ mtlr r10 addi r9,r1,STACK_FRAME_OVERHEAD
--
2.5.5