From: Oleg Nesterov <oleg@redhat.com>
Date: Sun, 26 Apr 2009 23:41:34 +0000 (+0200)
Subject: ptrace: ptrace_attach: fix the usage of ->cred_exec_mutex
X-Git-Tag: v2.6.29.3~30
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2c9ca2baf3f368a2b747124d39bf31b779eb7571;p=thirdparty%2Fkernel%2Fstable.git

ptrace: ptrace_attach: fix the usage of ->cred_exec_mutex

commit cad81bc2529ab8c62b6fdc83a1c0c7f4a87209eb upstream.

ptrace_attach() needs task->cred_exec_mutex, not current->cred_exec_mutex.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index c9cf48b21f052..dc3b98ef10bb0 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -186,7 +186,7 @@ int ptrace_attach(struct task_struct *task)
 	/* Protect exec's credential calculations against our interference;
 	 * SUID, SGID and LSM creds get determined differently under ptrace.
 	 */
-	retval = mutex_lock_interruptible(&current->cred_exec_mutex);
+	retval = mutex_lock_interruptible(&task->cred_exec_mutex);
 	if (retval  < 0)
 		goto out;
 
@@ -230,7 +230,7 @@ repeat:
 bad:
 	write_unlock_irqrestore(&tasklist_lock, flags);
 	task_unlock(task);
-	mutex_unlock(&current->cred_exec_mutex);
+	mutex_unlock(&task->cred_exec_mutex);
 out:
 	return retval;
 }