On Tue, Dec 22, 2020 at 09:22:19AM -0700, Tycho Andersen wrote: > On Mon, Dec 21, 2020 at 11:52:00PM +0100, Andreas Schwab wrote: > > Properly return -ENOSYS for syscall -1 instead of leaving the return value > > uninitialized. This fixes the strace teststuite. > > > > Fixes: 5340627e3fe0 ("riscv: add support for SECCOMP and SECCOMP_FILTER") > > Signed-off-by: Andreas Schwab <sch...@suse.de> > > --- > > arch/riscv/kernel/entry.S | 9 +-------- > > 1 file changed, 1 insertion(+), 8 deletions(-) > > > > diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S > > index 524d918f3601..d07763001eb0 100644 > > --- a/arch/riscv/kernel/entry.S > > +++ b/arch/riscv/kernel/entry.S > > @@ -186,14 +186,7 @@ check_syscall_nr: > > * Syscall number held in a7. > > * If syscall number is above allowed value, redirect to ni_syscall. > > */ > > - bge a7, t0, 1f > > - /* > > - * Check if syscall is rejected by tracer, i.e., a7 == -1. > > - * If yes, we pretend it was executed. > > - */ > > - li t1, -1 > > - beq a7, t1, ret_from_syscall_rejected > > - blt a7, t1, 1f > > + bgeu a7, t0, 1f > > IIUC, this is all dead code anyway for the path where seccomp actually > rejects the syscall, since it should do the rejection directly in > handle_syscall_trace_enter(), which is called above this hunk. So it > seems good to me.
That change really needs to be documented in the commit log, or even better split into a separate patch (still documented of course!).