[PATCH v2] net: hams: Fix deadlock caused by unsafe-irq lock in sp_get()

From: Jeongjun Park
Date: Fri Apr 19 2024 - 13:44:17 EST



read_lock() present in sp_get() is interrupt-vulnerable, so the function needs to be modified.


Reported-by: syzbot+8e03da5d64bc85098811@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Jeongjun Park <aha310510@xxxxxxxxx>
---
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