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Reported-by: syzbot+393d0ef63475d9bb1f16@syzkaller.appspotmail.com Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Jeongjun Park --- drivers/net/ppp/ppp_async.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/net/ppp/ppp_async.c b/drivers/net/ppp/ppp_async.c index c33c3db3cc08..dc1d4633428a 100644 --- a/drivers/net/ppp/ppp_async.c +++ b/drivers/net/ppp/ppp_async.c @@ -133,12 +133,13 @@ static DEFINE_RWLOCK(disc_data_lock); static struct asyncppp *ap_get(struct tty_struct *tty) { struct asyncppp *ap; + unsigned long flags; =20 - read_lock(&disc_data_lock); + flags =3D read_lock_irqsave(&disc_data_lock); ap =3D tty->disc_data; if (ap !=3D NULL) refcount_inc(&ap->refcnt); - read_unlock(&disc_data_lock); + read_unlock_irqrestore(&disc_data_lock, flags); return ap; } =20 --=20 2.34.1