CVS commit: src/sys/arch/amd64/amd64

[Maxime Villard]

Module Name:    src
Committed By:   maxv
Date:           Tue Jul 25 18:03:56 UTC 2017

Modified Files:
        src/sys/arch/amd64/amd64: netbsd32_machdep.c

Log Message:
This branch must be static, otherwise there is a condition under which
the KASSERT in startlwp32 would be triggered.


To generate a diff of this commit:
cvs rdiff -u -r1.106 -r1.107 src/sys/arch/amd64/amd64/netbsd32_machdep.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/netbsd32_machdep.c
diff -u src/sys/arch/amd64/amd64/netbsd32_machdep.c:1.106 src/sys/arch/amd64/amd64/netbsd32_machdep.c:1.107
--- src/sys/arch/amd64/amd64/netbsd32_machdep.c:1.106	Sat Jul 22 13:00:42 2017
+++ src/sys/arch/amd64/amd64/netbsd32_machdep.c	Tue Jul 25 18:03:56 2017
@@ -1,4 +1,4 @@
-/*	$NetBSD: netbsd32_machdep.c,v 1.106 2017/07/22 13:00:42 maxv Exp $	*/
+/*	$NetBSD: netbsd32_machdep.c,v 1.107 2017/07/25 18:03:56 maxv Exp $	*/
 
 /*
  * Copyright (c) 2001 Wasabi Systems, Inc.
@@ -36,7 +36,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: netbsd32_machdep.c,v 1.106 2017/07/22 13:00:42 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: netbsd32_machdep.c,v 1.107 2017/07/25 18:03:56 maxv Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_compat_netbsd.h"
@@ -1086,37 +1086,36 @@ check_sigcontext32(struct lwp *l, const 
 int
 cpu_mcontext32_validate(struct lwp *l, const mcontext32_t *mcp)
 {
-	struct pmap *pmap = l->l_proc->p_vmspace->vm_map.pmap;
 	const __greg32_t *gr;
 	struct trapframe *tf;
-	struct pcb *pcb;
 
 	gr = mcp->__gregs;
 	tf = l->l_md.md_regs;
-	pcb = lwp_getpcb(l);
 
 	if (((gr[_REG32_EFL] ^ tf->tf_rflags) & PSL_USERSTATIC) != 0)
 		return EINVAL;
 
-	if (__predict_false(pmap->pm_ldt != NULL)) {
-		/* Only when the LDT is user-set (with USER_LDT) */
-		if (!USERMODE(gr[_REG32_CS], gr[_REG32_EFL]))
-			return EINVAL;
-	} else {
-		if (!VALID_USER_CSEL32(gr[_REG32_CS]))
-			return EINVAL;
-		if (gr[_REG32_FS] != 0 && !VALID_USER_DSEL32(gr[_REG32_FS]) &&
-		    !(VALID_USER_FSEL32(gr[_REG32_FS]) && pcb->pcb_fs != 0))
-			return EINVAL;
-		if (gr[_REG32_GS] != 0 && !VALID_USER_DSEL32(gr[_REG32_GS]) &&
-		    !(VALID_USER_GSEL32(gr[_REG32_GS]) && pcb->pcb_gs != 0))
-			return EINVAL;
-		if (gr[_REG32_ES] != 0 && !VALID_USER_DSEL32(gr[_REG32_ES]))
-			return EINVAL;
-		if (!VALID_USER_DSEL32(gr[_REG32_DS]) ||
-		    !VALID_USER_DSEL32(gr[_REG32_SS]))
-			return EINVAL;
-	}
+#ifdef USER_LDT
+	/* Userland is allowed to have unfamiliar segment register values */
+	if (!USERMODE(gr[_REG32_CS], gr[_REG32_EFL]))
+		return EINVAL;
+#else
+	struct pcb *pcb = lwp_getpcb(l);
+
+	if (!VALID_USER_CSEL32(gr[_REG32_CS]))
+		return EINVAL;
+	if (gr[_REG32_FS] != 0 && !VALID_USER_DSEL32(gr[_REG32_FS]) &&
+	    !(VALID_USER_FSEL32(gr[_REG32_FS]) && pcb->pcb_fs != 0))
+		return EINVAL;
+	if (gr[_REG32_GS] != 0 && !VALID_USER_DSEL32(gr[_REG32_GS]) &&
+	    !(VALID_USER_GSEL32(gr[_REG32_GS]) && pcb->pcb_gs != 0))
+		return EINVAL;
+	if (gr[_REG32_ES] != 0 && !VALID_USER_DSEL32(gr[_REG32_ES]))
+		return EINVAL;
+	if (!VALID_USER_DSEL32(gr[_REG32_DS]) ||
+	    !VALID_USER_DSEL32(gr[_REG32_SS]))
+		return EINVAL;
+#endif
 
 	if (gr[_REG32_EIP] >= VM_MAXUSER_ADDRESS32)
 		return EINVAL;