From: Jeongjun Park <aha310510@gmail.com>
To: syzbot+393d0ef63475d9bb1f16@syzkaller.appspotmail.com
Cc: davem@davemloft.net, edumazet@google.com, kuba@kernel.org,
linux-kernel@vger.kernel.org, linux-ppp@vger.kernel.org,
netdev@vger.kernel.org, pabeni@redhat.com,
syzkaller-bugs@googlegroups.com,
Jeongjun Park <aha310510@gmail.com>
Subject: [PATCH net,v2] net: ppp: Fix deadlock caused by unsafe-irq lock in ap_get()
Date: Sat, 20 Apr 2024 03:12:38 +0900 [thread overview]
Message-ID: <20240419181238.29399-1-aha310510@gmail.com> (raw)
In-Reply-To: <000000000000423dd10611261d47@google.com>
read_lock() present in ap_get() is interrupt-vulnerable, so the function needs to be modified.
Reported-by: syzbot+393d0ef63475d9bb1f16@syzkaller.appspotmail.com
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
---
drivers/net/ppp/ppp_async.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ppp/ppp_async.c b/drivers/net/ppp/ppp_async.c
index c33c3db3cc08..d12b8155e839 100644
--- a/drivers/net/ppp/ppp_async.c
+++ b/drivers/net/ppp/ppp_async.c
@@ -134,11 +134,11 @@ static struct asyncppp *ap_get(struct tty_struct *tty)
{
struct asyncppp *ap;
- read_lock(&disc_data_lock);
+ read_lock_irq(&disc_data_lock);
ap = tty->disc_data;
if (ap != NULL)
refcount_inc(&ap->refcnt);
- read_unlock(&disc_data_lock);
+ read_unlock_irq(&disc_data_lock);
return ap;
}
--
2.34.1
next prev parent reply other threads:[~2024-04-19 18:13 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-02-12 2:34 [syzbot] [ppp?] possible deadlock in ppp_asynctty_receive (2) syzbot
2024-04-19 18:12 ` Jeongjun Park [this message]
2024-04-19 18:38 ` [PATCH net,v3] net: ppp: Fix deadlock caused by unsafe-irq lock in ap_get() Jeongjun Park
2024-04-20 0:31 ` Jakub Kicinski
2024-04-22 6:39 ` Jiri Slaby
2024-04-22 7:18 ` Jeongjun Park
2024-04-22 7:29 ` Jiri Slaby
2024-04-22 8:58 ` Jeongjun Park
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