[PATCH 5.11 684/775] mailbox: arm_mhuv2: Skip calling kfree() with invalid pointer

[Greg Kroah-Hartman]

From: Viresh Kumar <viresh.kumar@xxxxxxxxxx>

commit 6b50df2b8c208a04d44b8df5b7baaf668ceb8fc3 upstream.

It is possible that 'data' passed to kfree() is set to a error value
instead of allocated space. Make sure it doesn't get called with invalid
pointer.

Fixes: 5a6338cce9f4 ("mailbox: arm_mhuv2: Add driver")
Cc: v5.11 <stable@xxxxxxxxxxxxxxx> # v5.11
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Signed-off-by: Jassi Brar <jaswinder.singh@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/mailbox/arm_mhuv2.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/mailbox/arm_mhuv2.c
+++ b/drivers/mailbox/arm_mhuv2.c
@@ -699,7 +699,9 @@ static irqreturn_t mhuv2_receiver_interr
 		ret = IRQ_HANDLED;
 	}
 
-	kfree(data);
+	if (!IS_ERR(data))
+		kfree(data);
+
 	return ret;
 }