[PATCH] power: sequencing: fix NULL-pointer dereference in error path

[Bartosz Golaszewski]

From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>

We may call pwrseq_target_free() on a target without the final unit
assigned yet. In this case pwrseq_unit_put() will dereference
a NULL-pointer. Add a check to the latter function.

Fixes: 249ebf3f65f8 ("power: sequencing: implement the pwrseq core")
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Closes: https://lore.kernel.org/linux-pm/62a3531e-9927-40f8-b587-254a2dfa47ef@stanley.mountain/
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
---
 drivers/power/sequencing/core.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/power/sequencing/core.c b/drivers/power/sequencing/core.c
index 9c32b07a55e7..fe07100e4b33 100644
--- a/drivers/power/sequencing/core.c
+++ b/drivers/power/sequencing/core.c
@@ -119,7 +119,8 @@ static void pwrseq_unit_release(struct kref *ref);
 
 static void pwrseq_unit_put(struct pwrseq_unit *unit)
 {
-	kref_put(&unit->ref, pwrseq_unit_release);
+	if (unit)
+		kref_put(&unit->ref, pwrseq_unit_release);
 }
 
 /**
-- 
2.43.0