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From: Jeongjun Park <aha310510@gmail.com>
To: syzbot+8e03da5d64bc85098811@syzkaller.appspotmail.com
Cc: ajk@comnets.uni-bremen.de,
	davem@davemloft.net,
	edumazet@google.com,
	kuba@kernel.org,
	linux-hams@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	netdev@vger.kernel.org,
	pabeni@redhat.com,
	syzkaller-bugs@googlegroups.com,
	Jeongjun Park <aha310510@gmail.com>
Subject: [PATCH v2] net: hams: Fix deadlock caused by unsafe-irq lock in sp_get()
Date: Sat, 20 Apr 2024 02:43:21 +0900
Message-Id: <20240419174319.28528-1-aha310510@gmail.com>
In-Reply-To: <0000000000005e18f00615207de6@google.com>
References: <0000000000005e18f00615207de6@google.com>
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read_lock() present in sp_get() is interrupt-vulnerable, so the function needs to be modified.


Reported-by: syzbot+8e03da5d64bc85098811@syzkaller.appspotmail.com
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
---
 drivers/net/hamradio/6pack.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/hamradio/6pack.c b/drivers/net/hamradio/6pack.c
index 6ed38a3cdd73..fee583b1e59a 100644
--- a/drivers/net/hamradio/6pack.c
+++ b/drivers/net/hamradio/6pack.c
@@ -373,11 +373,11 @@ static struct sixpack *sp_get(struct tty_struct *tty)
 {
 	struct sixpack *sp;
 
-	read_lock(&disc_data_lock);
+	read_lock_irq(&disc_data_lock);
 	sp = tty->disc_data;
 	if (sp)
 		refcount_inc(&sp->refcnt);
-	read_unlock(&disc_data_lock);
+	read_unlock_irq(&disc_data_lock);
 
 	return sp;
 }
-- 
2.34.1