On Tue, Sep 10, 2019 at 10:01:22PM -0300, Thadeu Lima de Souza Cascardo wrote: > If a tracer sets the syscall number to an invalid one, allow the return > value set by the tracer to be returned the tracee. > > The test for NR_syscalls is already at entry_64.S, and it's at > do_syscall_trace_enter only to skip audit and trace. > > After this, seccomp_bpf selftests complete just fine, as the failing test > was using ptrace to change the syscall to return an error or a fake value, > but were failing as it was always returning -ENOSYS. > > Signed-off-by: Thadeu Lima de Souza Cascardo <casca...@canonical.com> > --- > arch/powerpc/kernel/ptrace.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c > index 8c92febf5f44..87315335f66a 100644 > --- a/arch/powerpc/kernel/ptrace.c > +++ b/arch/powerpc/kernel/ptrace.c > @@ -3316,7 +3316,7 @@ long do_syscall_trace_enter(struct pt_regs *regs) > > /* Avoid trace and audit when syscall is invalid. */ > if (regs->gpr[0] >= NR_syscalls) > - goto skip; > + return regs->gpr[0]; > > if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT))) > trace_sys_enter(regs, regs->gpr[0]);
Ping? Any comments on this? Thanks. Cascardo.