Module Name: src
Committed By: snj
Date: Thu Jul 20 01:42:40 UTC 2017
Modified Files:
src/sys/arch/amd64/amd64 [netbsd-7-0]: locore.S
src/sys/arch/i386/i386 [netbsd-7-0]: locore.S machdep.c trap.c
Log Message:
Pull up following revision(s) (requested by maxv in ticket #1441):
sys/arch/i386/i386/trap.c: revision 1.288 via patch
sys/arch/i386/i386/machdep.c: revision 1.783 via patch
sys/arch/i386/i386/locore.S: revision 1.146 via patch
sys/arch/amd64/amd64/locore.S: revision 1.124 via patch
Remove the osyscall call gate on i386, and emulate it. There is a one-
instruction race in it that could panic the kernel.
To generate a diff of this commit:
cvs rdiff -u -r1.76.4.1 -r1.76.4.2 src/sys/arch/amd64/amd64/locore.S
cvs rdiff -u -r1.112 -r1.112.6.1 src/sys/arch/i386/i386/locore.S
cvs rdiff -u -r1.752 -r1.752.8.1 src/sys/arch/i386/i386/machdep.c
cvs rdiff -u -r1.272.6.1 -r1.272.6.2 src/sys/arch/i386/i386/trap.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/amd64/amd64/locore.S
diff -u src/sys/arch/amd64/amd64/locore.S:1.76.4.1 src/sys/arch/amd64/amd64/locore.S:1.76.4.2
--- src/sys/arch/amd64/amd64/locore.S:1.76.4.1 Wed Apr 26 14:50:51 2017
+++ src/sys/arch/amd64/amd64/locore.S Thu Jul 20 01:42:39 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: locore.S,v 1.76.4.1 2017/04/26 14:50:51 martin Exp $ */
+/* $NetBSD: locore.S,v 1.76.4.2 2017/07/20 01:42:39 snj Exp $ */
/*
* Copyright-o-rama!
@@ -1298,7 +1298,6 @@ IDTVEC(osyscall)
addq $0x10,%rsp
#endif
pushq $2 # size of instruction for restart
-osyscall1:
pushq $T_ASTFLT # trap # for doing ASTs
INTRENTRY
STI(si)
Index: src/sys/arch/i386/i386/locore.S
diff -u src/sys/arch/i386/i386/locore.S:1.112 src/sys/arch/i386/i386/locore.S:1.112.6.1
--- src/sys/arch/i386/i386/locore.S:1.112 Thu Feb 20 18:19:10 2014
+++ src/sys/arch/i386/i386/locore.S Thu Jul 20 01:42:39 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: locore.S,v 1.112 2014/02/20 18:19:10 dsl Exp $ */
+/* $NetBSD: locore.S,v 1.112.6.1 2017/07/20 01:42:39 snj Exp $ */
/*
* Copyright-o-rama!
@@ -129,7 +129,7 @@
*/
#include <machine/asm.h>
-__KERNEL_RCSID(0, "$NetBSD: locore.S,v 1.112 2014/02/20 18:19:10 dsl Exp $");
+__KERNEL_RCSID(0, "$NetBSD: locore.S,v 1.112.6.1 2017/07/20 01:42:39 snj Exp $");
#include "opt_compat_oldboot.h"
#include "opt_ddb.h"
@@ -1144,30 +1144,12 @@ ENTRY(savectx)
END(savectx)
/*
- * osyscall()
- *
- * Old call gate entry for syscall
- */
-IDTVEC(osyscall)
-#ifndef XEN
- /* XXX we are in trouble! interrupts be off here. */
- cli # must be first instruction
-#endif
- pushfl # set eflags in trap frame
- popl 8(%esp)
- orl $PSL_I,8(%esp) # re-enable ints on return to user
- pushl $7 # size of instruction for restart
- jmp syscall1
-IDTVEC_END(osyscall)
-
-/*
* syscall()
*
* Trap gate entry for syscall
*/
IDTVEC(syscall)
pushl $2 # size of instruction for restart
-syscall1:
pushl $T_ASTFLT # trap # for doing ASTs
INTRENTRY
STI(%eax)
Index: src/sys/arch/i386/i386/machdep.c
diff -u src/sys/arch/i386/i386/machdep.c:1.752 src/sys/arch/i386/i386/machdep.c:1.752.8.1
--- src/sys/arch/i386/i386/machdep.c:1.752 Sun Feb 23 22:36:43 2014
+++ src/sys/arch/i386/i386/machdep.c Thu Jul 20 01:42:39 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: machdep.c,v 1.752 2014/02/23 22:36:43 dsl Exp $ */
+/* $NetBSD: machdep.c,v 1.752.8.1 2017/07/20 01:42:39 snj Exp $ */
/*-
* Copyright (c) 1996, 1997, 1998, 2000, 2004, 2006, 2008, 2009
@@ -67,7 +67,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: machdep.c,v 1.752 2014/02/23 22:36:43 dsl Exp $");
+__KERNEL_RCSID(0, "$NetBSD: machdep.c,v 1.752.8.1 2017/07/20 01:42:39 snj Exp $");
#include "opt_beep.h"
#include "opt_compat_ibcs2.h"
@@ -924,7 +924,6 @@ setsegment(struct segment_descriptor *sd
#define IDTVEC(name) __CONCAT(X, name)
typedef void (vector)(void);
extern vector IDTVEC(syscall);
-extern vector IDTVEC(osyscall);
extern vector *IDTVEC(exceptions)[];
extern vector IDTVEC(svr4_fasttrap);
void (*svr4_fasttrap_vec)(void) = (void (*)(void))nullop;
@@ -1345,13 +1344,9 @@ init386(paddr_t first_avail)
#endif /* XEN */
/* make ldt gates and memory segments */
- setgate(&ldt[LSYS5CALLS_SEL].gd, &IDTVEC(osyscall), 1,
- SDT_SYS386CGT, SEL_UPL, GSEL(GCODE_SEL, SEL_KPL));
-
ldt[LUCODE_SEL] = gdt[GUCODE_SEL];
ldt[LUCODEBIG_SEL] = gdt[GUCODEBIG_SEL];
ldt[LUDATA_SEL] = gdt[GUDATA_SEL];
- ldt[LSOL26CALLS_SEL] = ldt[LBSDICALLS_SEL] = ldt[LSYS5CALLS_SEL];
#ifndef XEN
/* exceptions */
Index: src/sys/arch/i386/i386/trap.c
diff -u src/sys/arch/i386/i386/trap.c:1.272.6.1 src/sys/arch/i386/i386/trap.c:1.272.6.2
--- src/sys/arch/i386/i386/trap.c:1.272.6.1 Sat Mar 25 16:59:01 2017
+++ src/sys/arch/i386/i386/trap.c Thu Jul 20 01:42:39 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: trap.c,v 1.272.6.1 2017/03/25 16:59:01 snj Exp $ */
+/* $NetBSD: trap.c,v 1.272.6.2 2017/07/20 01:42:39 snj Exp $ */
/*-
* Copyright (c) 1998, 2000, 2005, 2006, 2007, 2008 The NetBSD Foundation, Inc.
@@ -68,7 +68,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.272.6.1 2017/03/25 16:59:01 snj Exp $");
+__KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.272.6.2 2017/07/20 01:42:39 snj Exp $");
#include "opt_ddb.h"
#include "opt_kgdb.h"
@@ -78,6 +78,7 @@ __KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.2
#include "opt_kstack_dr0.h"
#include "opt_xen.h"
#include "opt_dtrace.h"
+#include "opt_compat_netbsd.h"
#include <sys/param.h>
#include <sys/systm.h>
@@ -265,8 +266,7 @@ trap(struct trapframe *frame)
struct lwp *l = curlwp;
struct proc *p;
struct pcb *pcb;
- extern char fusubail[], kcopy_fault[], return_address_fault[],
- IDTVEC(osyscall)[];
+ extern char fusubail[], kcopy_fault[], return_address_fault[];
struct trapframe *vframe;
ksiginfo_t ksi;
void *onfault;
@@ -439,6 +439,26 @@ kernelfault:
/* NOTREACHED */
case T_PROTFLT|T_USER: /* protection fault */
+#if defined(COMPAT_10)
+ {
+ static const char lcall[7] = { 0x9a, 0, 0, 0, 0, 7, 0 };
+ const size_t sz = sizeof(lcall);
+ char tmp[sz];
+
+ /* Check for the osyscall lcall instruction. */
+ if (frame->tf_eip < VM_MAXUSER_ADDRESS - sz &&
+ copyin((void *)frame->tf_eip, tmp, sz) == 0 &&
+ memcmp(tmp, lcall, sz) == 0) {
+
+ /* Advance past the lcall. */
+ frame->tf_eip += sz;
+
+ /* Do the syscall. */
+ p->p_md.md_syscall(frame);
+ goto out;
+ }
+ }
+#endif
case T_TSSFLT|T_USER:
case T_SEGNPFLT|T_USER:
case T_STKFLT|T_USER:
@@ -686,13 +706,6 @@ faultcommon:
}
case T_TRCTRAP:
- /* Check whether they single-stepped into a lcall. */
- if (frame->tf_eip == (int)IDTVEC(osyscall))
- return;
- if (frame->tf_eip == (int)IDTVEC(osyscall) + 1) {
- frame->tf_eflags &= ~PSL_T;
- return;
- }
goto we_re_toast;
case T_BPTFLT|T_USER: /* bpt instruction fault */
