X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=kernel%2Fexit.c;h=8f6185e69b691265746f81a1ca4ce9de9fd8a640;hb=34a5d713056c325e5bf2b5361646585d5f550a72;hp=879ed6e1c88336fab0a7689b9240c6dab0899d76;hpb=2800d8d19e51414403df8144eaa214bb03400b87;p=linux-2.6

diff --git a/kernel/exit.c b/kernel/exit.c
index 879ed6e1c8..8f6185e69b 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -19,6 +19,7 @@
 #include <linux/acct.h>
 #include <linux/tsacct_kern.h>
 #include <linux/file.h>
+#include <linux/fdtable.h>
 #include <linux/binfmts.h>
 #include <linux/nsproxy.h>
 #include <linux/pid_namespace.h>
@@ -125,6 +126,12 @@ static void __exit_signal(struct task_struct *tsk)
 
 	__unhash_process(tsk);
 
+	/*
+	 * Do this under ->siglock, we can race with another thread
+	 * doing sigqueue_free() if we have SIGQUEUE_PREALLOC signals.
+	 */
+	flush_sigqueue(&tsk->pending);
+
 	tsk->signal = NULL;
 	tsk->sighand = NULL;
 	spin_unlock(&sighand->siglock);
@@ -132,7 +139,6 @@ static void __exit_signal(struct task_struct *tsk)
 
 	__cleanup_sighand(sighand);
 	clear_tsk_thread_flag(tsk,TIF_SIGPENDING);
-	flush_sigqueue(&tsk->pending);
 	if (sig) {
 		flush_sigqueue(&sig->shared_pending);
 		taskstats_tgid_free(sig);
@@ -334,13 +340,11 @@ void __set_special_pids(struct pid *pid)
 	pid_t nr = pid_nr(pid);
 
 	if (task_session(curr) != pid) {
-		detach_pid(curr, PIDTYPE_SID);
-		attach_pid(curr, PIDTYPE_SID, pid);
+		change_pid(curr, PIDTYPE_SID, pid);
 		set_task_session(curr, nr);
 	}
 	if (task_pgrp(curr) != pid) {
-		detach_pid(curr, PIDTYPE_PGID);
-		attach_pid(curr, PIDTYPE_PGID, pid);
+		change_pid(curr, PIDTYPE_PGID, pid);
 		set_task_pgrp(curr, nr);
 	}
 }
@@ -698,7 +702,7 @@ reparent_thread(struct task_struct *p, struct task_struct *father, int traced)
 	if (unlikely(traced)) {
 		/* Preserve ptrace links if someone else is tracing this child.  */
 		list_del_init(&p->ptrace_list);
-		if (p->parent != p->real_parent)
+		if (ptrace_reparented(p))
 			list_add(&p->ptrace_list, &p->real_parent->ptrace_children);
 	} else {
 		/* If this child is being traced, then we're the one tracing it
@@ -865,8 +869,8 @@ static void exit_notify(struct task_struct *tsk, int group_dead)
 	 * only has special meaning to our real parent.
 	 */
 	if (!task_detached(tsk) && thread_group_empty(tsk)) {
-		int signal = (tsk->parent == tsk->real_parent)
-				? tsk->exit_signal : SIGCHLD;
+		int signal = ptrace_reparented(tsk) ?
+				SIGCHLD : tsk->exit_signal;
 		do_notify_parent(tsk, signal);
 	} else if (tsk->ptrace) {
 		do_notify_parent(tsk, SIGCHLD);
@@ -1269,8 +1273,7 @@ static int wait_task_zombie(struct task_struct *p, int noreap,
 		return 0;
 	}
 
-	/* traced means p->ptrace, but not vice versa */
-	traced = (p->real_parent != p->parent);
+	traced = ptrace_reparented(p);
 
 	if (likely(!traced)) {
 		struct signal_struct *psig;