From ba0fbdb95da5ddd8db457ce6ba09d16dd979a294 Mon Sep 17 00:00:00 2001
From: Maxim Mikityanskiy <maxtram95@gmail.com>
Date: Sat, 1 Oct 2022 13:57:13 +0300
Subject: [PATCH] net: wwan: iosm: Call mutex_init before locking it
Git-commit: ba0fbdb95da5ddd8db457ce6ba09d16dd979a294
Patch-mainline: v6.1-rc1
References: git-fixes

wwan_register_ops calls wwan_create_default_link, which ends up in the
ipc_wwan_newlink callback that locks ipc_wwan->if_mutex. However, this
mutex is not yet initialized by that point. Fix it by moving mutex_init
above the wwan_register_ops call. This also makes the order of
operations in ipc_wwan_init symmetric to ipc_wwan_deinit.

Fixes: 83068395bbfc ("net: iosm: create default link via WWAN core")
Signed-off-by: Maxim Mikityanskiy <maxtram95@gmail.com>
Reviewed-by: M Chetan Kumar <m.chetan.kumar@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/net/wwan/iosm/iosm_ipc_wwan.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wwan/iosm/iosm_ipc_wwan.c b/drivers/net/wwan/iosm/iosm_ipc_wwan.c
index 27151148c782..4712f01a7e33 100644
--- a/drivers/net/wwan/iosm/iosm_ipc_wwan.c
+++ b/drivers/net/wwan/iosm/iosm_ipc_wwan.c
@@ -323,15 +323,16 @@ struct iosm_wwan *ipc_wwan_init(struct iosm_imem *ipc_imem, struct device *dev)
 	ipc_wwan->dev = dev;
 	ipc_wwan->ipc_imem = ipc_imem;
 
+	mutex_init(&ipc_wwan->if_mutex);
+
 	/* WWAN core will create a netdev for the default IP MUX channel */
 	if (wwan_register_ops(ipc_wwan->dev, &iosm_wwan_ops, ipc_wwan,
 			      IP_MUX_SESSION_DEFAULT)) {
+		mutex_destroy(&ipc_wwan->if_mutex);
 		kfree(ipc_wwan);
 		return NULL;
 	}
 
-	mutex_init(&ipc_wwan->if_mutex);
-
 	return ipc_wwan;
 }
 
-- 
2.35.3