[PATCH 3/4] sh: Add SECCOMP_FILTER

From: Michael Karcher <kernel@mkarcher.dialup.fu-berlin.de>
To: linux-sh@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>,
	Rich Felker <dalias@libc.org>,
	Adrian Glaubitz <glaubitz@physik.fu-berlin.de>,
	Michael Karcher <kernel@mkarcher.dialup.fu-berlin.de>
Subject: [PATCH 3/4] sh: Add SECCOMP_FILTER
Date: Wed, 22 Jul 2020 23:13:21 +0000
Message-ID: <20200722231322.419642-3-kernel@mkarcher.dialup.fu-berlin.de> (raw)
In-Reply-To: <20200722231322.419642-1-kernel@mkarcher.dialup.fu-berlin.de>

Port sh to use the new SECCOMP_FILTER code.

Signed-off-by: Michael Karcher <kernel@mkarcher.dialup.fu-berlin.de>
---
 arch/sh/Kconfig                               | 1 +
 arch/sh/kernel/entry-common.S                 | 2 ++
 arch/sh/kernel/ptrace_32.c                    | 5 +++--
 tools/testing/selftests/seccomp/seccomp_bpf.c | 8 +++++++-
 4 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 32d959849df9..10b510c16841 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -27,6 +27,7 @@ config SUPERH
 	select GENERIC_SMP_IDLE_THREAD
 	select GUP_GET_PTE_LOW_HIGH if X2TLB
 	select HAVE_ARCH_AUDITSYSCALL
+	select HAVE_ARCH_SECCOMP_FILTER
 	select HAVE_ARCH_KGDB
 	select HAVE_ARCH_TRACEHOOK
 	select HAVE_DEBUG_BUGVERBOSE
diff --git a/arch/sh/kernel/entry-common.S b/arch/sh/kernel/entry-common.S
index c4d88d61890d..ad963104d22d 100644
--- a/arch/sh/kernel/entry-common.S
+++ b/arch/sh/kernel/entry-common.S
@@ -368,6 +368,8 @@ syscall_trace_entry:
 	mov.l	7f, r11		! Call do_syscall_trace_enter which notifies
 	jsr	@r11	    	! superior (will chomp R[0-7])
 	 nop
+	cmp/eq	#-1, r0
+	bt	syscall_exit
 	mov.l	r0, @(OFF_R0,r15)	! Save return value
 	!			Reload R0-R4 from kernel stack, where the
 	!   	    	    	parent may have modified them using
diff --git a/arch/sh/kernel/ptrace_32.c b/arch/sh/kernel/ptrace_32.c
index 64bfb714943e..25ccfbd02bfa 100644
--- a/arch/sh/kernel/ptrace_32.c
+++ b/arch/sh/kernel/ptrace_32.c
@@ -485,8 +485,6 @@ asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
 {
 	long ret = 0;
 
-	secure_computing_strict(regs->regs[0]);
-
 	if (test_thread_flag(TIF_SYSCALL_TRACE) &&
 	    tracehook_report_syscall_entry(regs))
 		/*
@@ -496,6 +494,9 @@ asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
 		 */
 		ret = -1L;
 
+	if (secure_computing() = -1)
+		return -1;
+
 	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 		trace_sys_enter(regs, regs->regs[0]);
 
diff --git a/tools/testing/selftests/seccomp/seccomp_bpf.c b/tools/testing/selftests/seccomp/seccomp_bpf.c
index 252140a52553..6eb21685c88f 100644
--- a/tools/testing/selftests/seccomp/seccomp_bpf.c
+++ b/tools/testing/selftests/seccomp/seccomp_bpf.c
@@ -122,6 +122,8 @@ struct seccomp_data {
 #  define __NR_seccomp 358
 # elif defined(__s390__)
 #  define __NR_seccomp 348
+# elif defined(__sh__)
+#  define __NR_seccomp 372
 # else
 #  warning "seccomp syscall number unknown for this architecture"
 #  define __NR_seccomp 0xffff
@@ -1622,6 +1624,10 @@ TEST_F(TRACE_poke, getpid_runs_normally)
 # define SYSCALL_SYSCALL_NUM regs[4]
 # define SYSCALL_RET	regs[2]
 # define SYSCALL_NUM_RET_SHARE_REG
+#elif defined(__sh__)
+# define ARCH_REGS	struct pt_regs
+# define SYSCALL_NUM	gpr[3]
+# define SYSCALL_RET	gpr[0]
 #else
 # error "Do not know how to find your architecture's registers and syscalls"
 #endif
@@ -1693,7 +1699,7 @@ void change_syscall(struct __test_metadata *_metadata,
 	EXPECT_EQ(0, ret) {}
 
 #if defined(__x86_64__) || defined(__i386__) || defined(__powerpc__) || \
-	defined(__s390__) || defined(__hppa__) || defined(__riscv)
+	defined(__s390__) || defined(__hppa__) || defined(__riscv) || defined(__sh__)
 	{
 		regs.SYSCALL_NUM = syscall;
 	}
-- 
2.28.0.rc1
