From: Eric Paris <eparis@xxxxxxxxxx> SELinux has long been calling wake_up_interruptible() on current->parent->signal->wait_chldexit without holding any locks. It appears that this operation should hold the tasklist_lock to dereference current->parent and we should hold the siglock when waking up the signal->wait_chldexit. Signed-off-by: Eric Paris <eparis@xxxxxxxxxx> --- security/selinux/hooks.c | 7 +++++++ 1 files changed, 7 insertions(+), 0 deletions(-) diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index f85597a..1e45c6c 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -2269,7 +2269,9 @@ static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm) struct rlimit *rlim, *initrlim; struct itimerval itimer; struct bprm_security_struct *bsec; + struct sighand_struct *psig; int rc, i; + unsigned long flags; tsec = current->security; bsec = bprm->security; @@ -2330,7 +2332,12 @@ static void selinux_bprm_post_apply_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); } /* superblock security operations */ -- This message was distributed to subscribers of the selinux mailing list. If you no longer wish to subscribe, send mail to majordomo@xxxxxxxxxxxxx with the words "unsubscribe selinux" without quotes as the message.
