[PATCH] tty: make sure that proc_clear_tty stores the cpu flags

[Arjan van de Ven]

proc_clear_tty() gets called with interrupts off (while holding the task list lock)
from sys_setid. This means that it needs the _irqsave version of the locking primitives.

Reported-by: Marcin Slusarz <marcin.slusarz@xxxxxxxxx>
Signed-off-by: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
---
 drivers/char/tty_io.c |    5 +++--
 1 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index e4dce87..4715961 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -3595,9 +3595,10 @@ EXPORT_SYMBOL(tty_devnum);
 
 void proc_clear_tty(struct task_struct *p)
 {
-	spin_lock_irq(&p->sighand->siglock);
+	unsigned long flags;
+	spin_lock_irqsave(&p->sighand->siglock, flags);
 	p->signal->tty = NULL;
-	spin_unlock_irq(&p->sighand->siglock);
+	spin_unlock_irqrestore(&p->sighand->siglock, flags);
 }
 
 /* Called under the sighand lock */
-- 
1.5.5.1



-- 
Arjan van de Ven 	Intel Open Source Technology Centre
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