arm64: make sys_call_table const

commit c623b33b4e9599c6ac5076f7db7369eb9869aa04 upstream.

As with x86, mark the sys_call_table const such that it will be placed
in the .rodata section. This will cause attempts to modify the table
(accidental or deliberate) to fail when strict page permissions are in
place. In the absence of strict page permissions, there should be no
functional change.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/arm64/kernel/sys.c b/arch/arm64/kernel/sys.c
index 3fa98ff14f0eea5a536dd1bbc159d6161a0c9a0d..df20b79188549ef6771207c77d0b97e420c2fcd0 100644 (file)
--- a/arch/arm64/kernel/sys.c
+++ b/arch/arm64/kernel/sys.c
@@ -50,7 +50,7 @@ asmlinkage long sys_mmap(unsigned long addr, unsigned long len,
  * The sys_call_table array must be 4K aligned to be accessible from
  * kernel/entry.S.
  */
-void *sys_call_table[__NR_syscalls] __aligned(4096) = {
+void * const sys_call_table[__NR_syscalls] __aligned(4096) = {
        [0 ... __NR_syscalls - 1] = sys_ni_syscall,
 #include <asm/unistd.h>
 };