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From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org,
        =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= 
        <u.kleine-koenig@pengutronix.de>,
        Philipp Zabel <p.zabel@pengutronix.de>,
        Sasha Levin <sashal@kernel.org>
Subject: [PATCH 4.9 238/245] reset: bail if try_module_get() fails
Date:   Mon, 19 Jul 2021 16:53:00 +0200
Message-Id: <20210719144948.066708794@linuxfoundation.org>
In-Reply-To: <20210719144940.288257948@linuxfoundation.org>
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From: Philipp Zabel <p.zabel@pengutronix.de>

[ Upstream commit 4fb26fb83f0def3d39c14e268bcd4003aae8fade ]

Abort instead of returning a new reset control for a reset controller
device that is going to have its module unloaded.

Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Fixes: 61fc41317666 ("reset: Add reset controller API")
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210607082615.15160-1-p.zabel@pengutronix.de
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/reset/core.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/reset/core.c b/drivers/reset/core.c
index d0ebca301afc..c15c898fe0dc 100644
--- a/drivers/reset/core.c
+++ b/drivers/reset/core.c
@@ -263,7 +263,10 @@ static struct reset_control *__reset_control_get_internal(
 	if (!rstc)
 		return ERR_PTR(-ENOMEM);
 
-	try_module_get(rcdev->owner);
+	if (!try_module_get(rcdev->owner)) {
+		kfree(rstc);
+		return ERR_PTR(-ENODEV);
+	}
 
 	rstc->rcdev = rcdev;
 	list_add(&rstc->list, &rcdev->reset_control_head);
-- 
2.30.2