diff options
| author | Mark Kettenis <kettenis@cvs.openbsd.org> | 2020-02-18 12:19:12 +0000 |
|---|---|---|
| committer | Mark Kettenis <kettenis@cvs.openbsd.org> | 2020-02-18 12:19:12 +0000 |
| commit | abaeee0c2de5db354ea200288f678a16ca5ea4bb (patch) | |
| tree | 470771504e5b18405e7e6725c6b9836a6e05d677 /libexec | |
| parent | 7d507c040f5f8f249c657a3d207a3bf7bdc53eec (diff) | |
Now that the kernel skips the two instructions immediately following
a syscall, replace the double nop with a dsb nsh; isb; sequence which
stops the CPU from speculating any further. This fix was suggested
by Anthony Steinhauser.
ok deraadt@
Diffstat (limited to 'libexec')
| -rw-r--r-- | libexec/ld.so/aarch64/SYS.h | 6 | ||||
| -rw-r--r-- | libexec/ld.so/aarch64/rtld_machine.c | 4 |
2 files changed, 5 insertions, 5 deletions
diff --git a/libexec/ld.so/aarch64/SYS.h b/libexec/ld.so/aarch64/SYS.h index 46ed6aca5c0..08ec2a7b300 100644 --- a/libexec/ld.so/aarch64/SYS.h +++ b/libexec/ld.so/aarch64/SYS.h @@ -1,4 +1,4 @@ -/* $OpenBSD: SYS.h,v 1.4 2020/01/26 02:19:44 kettenis Exp $ */ +/* $OpenBSD: SYS.h,v 1.5 2020/02/18 12:19:11 kettenis Exp $ */ /* * Copyright (c) 2016 Dale Rahn @@ -32,8 +32,8 @@ #define SYSTRAP(x) \ ldr x8, =SYS_ ## x ;\ svc 0 ;\ - nop ;\ - nop + dsb nsh ;\ + isb #define DL_SYSCALL(n) \ .global __CONCAT(_dl_,n) ;\ diff --git a/libexec/ld.so/aarch64/rtld_machine.c b/libexec/ld.so/aarch64/rtld_machine.c index d466b5a1776..eac2a0cd124 100644 --- a/libexec/ld.so/aarch64/rtld_machine.c +++ b/libexec/ld.so/aarch64/rtld_machine.c @@ -1,4 +1,4 @@ -/* $OpenBSD: rtld_machine.c,v 1.19 2020/01/26 02:19:44 kettenis Exp $ */ +/* $OpenBSD: rtld_machine.c,v 1.20 2020/02/18 12:19:11 kettenis Exp $ */ /* * Copyright (c) 2004 Dale Rahn @@ -300,7 +300,7 @@ _dl_bind(elf_object_t *object, int relidx) register long arg2 __asm("x1") = sizeof(buf); register long arg3 __asm("x2") = cookie; - __asm volatile("svc 0; nop; nop" : "+r" (arg1), "+r" (arg2) + __asm volatile("svc 0; dsb nsh; isb" : "+r" (arg1), "+r" (arg2) : "r" (syscall_num), "r" (arg3) : "cc", "memory"); } |