tile/ptrace: run seccomp after ptrace

Close the hole where ptrace can change a syscall out from under seccomp.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Chris Metcalf <cmetcalf@mellanox.com>

1 files changed, 6 insertions, 5 deletions

diff --git a/arch/tile/kernel/ptrace.c b/arch/tile/kernel/ptrace.c
index 8c6d2f2fefa3..d89b7011667c 100644
--- a/arch/tile/kernel/ptrace.c
+++ b/arch/tile/kernel/ptrace.c
@@ -255,14 +255,15 @@ int do_syscall_trace_enter(struct pt_regs *regs)
 {
         u32 work = ACCESS_ONCE(current_thread_info()->flags);
 
-        if (secure_computing(NULL) == -1)
+        if ((work & _TIF_SYSCALL_TRACE) &&
+            tracehook_report_syscall_entry(regs)) {
+                regs->regs[TREG_SYSCALL_NR] = -1;
                 return -1;
-
-        if (work & _TIF_SYSCALL_TRACE) {
-                if (tracehook_report_syscall_entry(regs))
-                        regs->regs[TREG_SYSCALL_NR] = -1;
         }
 
+        if (secure_computing(NULL) == -1)
+                return -1;
+
         if (work & _TIF_SYSCALL_TRACEPOINT)
                 trace_sys_enter(regs, regs->regs[TREG_SYSCALL_NR]);