From ecd6de3c88e8cbcad175b2eab48ba05c2014f7b6 Mon Sep 17 00:00:00 2001 From: Oleg Nesterov Date: Wed, 29 Apr 2009 16:02:24 +0200 Subject: selinux: selinux_bprm_committed_creds() should wake up ->real_parent, not ->parent. We shouldn't worry about the tracer if current is ptraced, exec() must not succeed if the tracer has no rights to trace this task after cred changing. But we should notify ->real_parent which is, well, real parent. Also, we don't need _irq to take tasklist, and we don't need parent's ->siglock to wake_up_interruptible(real_parent->signal->wait_chldexit). Since we hold tasklist, real_parent->signal must be stable. Otherwise spin_lock(siglock) is not safe too and can't help anyway. Signed-off-by: Oleg Nesterov Signed-off-by: James Morris --- security/selinux/hooks.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) (limited to 'security/selinux') diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 5a345115036c..39046ddd90a9 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -2371,10 +2371,8 @@ static void selinux_bprm_committed_creds(struct linux_binprm *bprm) { const struct task_security_struct *tsec = current_security(); struct itimerval itimer; - struct sighand_struct *psig; u32 osid, sid; int rc, i; - unsigned long flags; osid = tsec->osid; sid = tsec->sid; @@ -2405,12 +2403,9 @@ static void selinux_bprm_committed_creds(struct linux_binprm *bprm) /* Wake up the parent if it is waiting so that it can recheck * wait permission to the new task SID. */ - read_lock_irq(&tasklist_lock); - psig = current->parent->sighand; - spin_lock_irqsave(&psig->siglock, flags); - wake_up_interruptible(¤t->parent->signal->wait_chldexit); - spin_unlock_irqrestore(&psig->siglock, flags); - read_unlock_irq(&tasklist_lock); + read_lock(&tasklist_lock); + wake_up_interruptible(¤t->real_parent->signal->wait_chldexit); + read_unlock(&tasklist_lock); } /* superblock security operations */ -- cgit v1.2.3