seccomp: ignore secure_computing return values

This change is inspired by
  https://lkml.org/lkml/2012/4/16/14
which fixes the build warnings for arches that don't support
CONFIG_HAVE_ARCH_SECCOMP_FILTER.

In particular, there is no requirement for the return value of
secure_computing() to be checked unless the architecture supports
seccomp filter.  Instead of silencing the warnings with (void)
a new static inline is added to encode the expected behavior
in a compiler and human friendly way.

v2: - cleans things up with a static inline
    - removes sfr's signed-off-by since it is a different approach
v1: - matches sfr's original change

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Will Drewry <wad@chromium.org>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <james.l.morris@oracle.com>

2 files changed, 2 insertions, 2 deletions

diff --git a/arch/sh/kernel/ptrace_32.c b/arch/sh/kernel/ptrace_32.c
index 9698671444e6..81f999a672f6 100644
--- a/arch/sh/kernel/ptrace_32.c
+++ b/arch/sh/kernel/ptrace_32.c
@@ -503,7 +503,7 @@ asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
 {
         long ret = 0;
 
-        secure_computing(regs->regs[0]);
+        secure_computing_strict(regs->regs[0]);
 
         if (test_thread_flag(TIF_SYSCALL_TRACE) &&
             tracehook_report_syscall_entry(regs))
diff --git a/arch/sh/kernel/ptrace_64.c b/arch/sh/kernel/ptrace_64.c
index bc81e07dc098..af90339dadcd 100644
--- a/arch/sh/kernel/ptrace_64.c
+++ b/arch/sh/kernel/ptrace_64.c
@@ -522,7 +522,7 @@ asmlinkage long long do_syscall_trace_enter(struct pt_regs *regs)
 {
         long long ret = 0;
 
-        secure_computing(regs->regs[9]);
+        secure_computing_strict(regs->regs[9]);
 
         if (test_thread_flag(TIF_SYSCALL_TRACE) &&
             tracehook_report_syscall_entry(regs))