[src/trunk]: src/sys/compat/linux/arch Don't release proc_lock until we're do...

[pgoyette <pgoyette%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/357d30744534
branches:  trunk
changeset: 340972:357d30744534
user:      pgoyette <pgoyette%NetBSD.org@localhost>
date:      Tue Oct 13 08:24:35 2015 +0000

description:
Don't release proc_lock until we're done looking at things that are
protected by the lock, particularly p_stat and p_waited.  Found by
Robert Elz.

XXX Pullup to NetBSD-7, -6, -6-0, and -6-1

diffstat:

 sys/compat/linux/arch/arm/linux_ptrace.c     |  8 +++++---
 sys/compat/linux/arch/i386/linux_ptrace.c    |  8 +++++---
 sys/compat/linux/arch/powerpc/linux_ptrace.c |  8 +++++---
 3 files changed, 15 insertions(+), 9 deletions(-)

diffs (138 lines):

diff -r f5bdbc551105 -r 357d30744534 sys/compat/linux/arch/arm/linux_ptrace.c
--- a/sys/compat/linux/arch/arm/linux_ptrace.c  Tue Oct 13 08:23:31 2015 +0000
+++ b/sys/compat/linux/arch/arm/linux_ptrace.c  Tue Oct 13 08:24:35 2015 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: linux_ptrace.c,v 1.18 2014/11/09 17:48:07 maxv Exp $   */
+/*     $NetBSD: linux_ptrace.c,v 1.19 2015/10/13 08:24:35 pgoyette Exp $       */
 
 /*-
  * Copyright (c) 1999 The NetBSD Foundation, Inc.
@@ -31,7 +31,7 @@
 
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: linux_ptrace.c,v 1.18 2014/11/09 17:48:07 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: linux_ptrace.c,v 1.19 2015/10/13 08:24:35 pgoyette Exp $");
 
 #include <sys/param.h>
 #include <sys/mount.h>
@@ -140,7 +140,6 @@
                goto out;
        }
        mutex_enter(t->p_lock);
-       mutex_exit(proc_lock);
 
        /*
         * You cannot do what you want to the process if:
@@ -148,6 +147,7 @@
         */
        if (!ISSET(t->p_slflag, PSL_TRACED)) {
                mutex_exit(t->p_lock);
+               mutex_exit(proc_lock);
                error = EPERM;
                goto out;
        }
@@ -160,9 +160,11 @@
        if (ISSET(t->p_slflag, PSL_FSTRACE) || t->p_pptr != p ||
            t->p_stat != SSTOP || !t->p_waited) {
                mutex_exit(t->p_lock);
+               mutex_exit(proc_lock);
                error = EBUSY;
                goto out;
        }
+       mutex_exit(proc_lock);
        /* XXX: ptrace needs revamp for multi-threading support. */
        if (t->p_nlwps > 1) {
                mutex_exit(t->p_lock);
diff -r f5bdbc551105 -r 357d30744534 sys/compat/linux/arch/i386/linux_ptrace.c
--- a/sys/compat/linux/arch/i386/linux_ptrace.c Tue Oct 13 08:23:31 2015 +0000
+++ b/sys/compat/linux/arch/i386/linux_ptrace.c Tue Oct 13 08:24:35 2015 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: linux_ptrace.c,v 1.30 2014/11/09 17:48:07 maxv Exp $   */
+/*     $NetBSD: linux_ptrace.c,v 1.31 2015/10/13 08:24:35 pgoyette Exp $       */
 
 /*-
  * Copyright (c) 1999 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: linux_ptrace.c,v 1.30 2014/11/09 17:48:07 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: linux_ptrace.c,v 1.31 2015/10/13 08:24:35 pgoyette Exp $");
 
 #include <sys/param.h>
 #include <sys/mount.h>
@@ -185,7 +185,6 @@
                goto out;
        }
        mutex_enter(t->p_lock);
-       mutex_exit(proc_lock);
 
        /*
         * You cannot do what you want to the process if:
@@ -193,6 +192,7 @@
         */
        if (!ISSET(t->p_slflag, PSL_TRACED)) {
                mutex_exit(t->p_lock);
+               mutex_exit(proc_lock);
                error = EPERM;
                goto out;
        }
@@ -205,9 +205,11 @@
        if (ISSET(t->p_slflag, PSL_FSTRACE) || t->p_pptr != p ||
            t->p_stat != SSTOP || !t->p_waited) {
                mutex_exit(t->p_lock);
+               mutex_exit(proc_lock);
                error = EBUSY;
                goto out;
        }
+       mutex_exit(proc_lock);
        /* XXX: ptrace needs revamp for multi-threading support. */
        if (t->p_nlwps > 1) {
                mutex_exit(t->p_lock);
diff -r f5bdbc551105 -r 357d30744534 sys/compat/linux/arch/powerpc/linux_ptrace.c
--- a/sys/compat/linux/arch/powerpc/linux_ptrace.c      Tue Oct 13 08:23:31 2015 +0000
+++ b/sys/compat/linux/arch/powerpc/linux_ptrace.c      Tue Oct 13 08:24:35 2015 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: linux_ptrace.c,v 1.28 2014/11/09 17:48:08 maxv Exp $ */
+/*     $NetBSD: linux_ptrace.c,v 1.29 2015/10/13 08:24:35 pgoyette Exp $ */
 
 /*-
  * Copyright (c) 1999, 2001 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: linux_ptrace.c,v 1.28 2014/11/09 17:48:08 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: linux_ptrace.c,v 1.29 2015/10/13 08:24:35 pgoyette Exp $");
 
 #include <sys/param.h>
 #include <sys/mount.h>
@@ -162,7 +162,6 @@
                goto out;
        }
        mutex_enter(t->p_lock);
-       mutex_exit(proc_lock);
 
        /*
         * You cannot do what you want to the process if:
@@ -170,6 +169,7 @@
         */
        if (!ISSET(t->p_slflag, PSL_TRACED)) {
                mutex_exit(t->p_lock);
+               mutex_exit(proc_lock);
                error = EPERM;
                goto out;
        }
@@ -182,9 +182,11 @@
        if (ISSET(t->p_slflag, PSL_FSTRACE) || t->p_pptr != p ||
            t->p_stat != SSTOP || !t->p_waited) {
                mutex_exit(t->p_lock);
+               mutex_exit(proc_lock);
                error = EBUSY;
                goto out;
        }
+       mutex_exit(proc_lock);
        /* XXX: ptrace needs revamp for multi-threading support. */
        if (t->p_nlwps > 1) {
                mutex_exit(t->p_lock);