From: Peng Fan <peng.fan@nxp.com>
Date: Fri, 11 Apr 2025 13:14:10 +0000 (+0800)
Subject: mailbox: Not protect module_put with spin_lock_irqsave
X-Git-Tag: v5.10.240~204
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=e693e083aafe1ec98c0862fd1b51b4c6a9e0466f;p=thirdparty%2Fkernel%2Fstable.git

mailbox: Not protect module_put with spin_lock_irqsave

[ Upstream commit dddbd233e67e792bb0a3f9694a4707e6be29b2c6 ]

&chan->lock is not supposed to protect 'chan->mbox'.
And in __mbox_bind_client, try_module_get is also not protected
by &chan->lock. So move module_put out of the lock protected
region.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Jassi Brar <jassisinghbrar@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c
index 6f54501dc7762..cb31ad917b352 100644
--- a/drivers/mailbox/mailbox.c
+++ b/drivers/mailbox/mailbox.c
@@ -459,8 +459,8 @@ void mbox_free_channel(struct mbox_chan *chan)
 	if (chan->txdone_method == TXDONE_BY_ACK)
 		chan->txdone_method = TXDONE_BY_POLL;
 
-	module_put(chan->mbox->dev->driver->owner);
 	spin_unlock_irqrestore(&chan->lock, flags);
+	module_put(chan->mbox->dev->driver->owner);
 }
 EXPORT_SYMBOL_GPL(mbox_free_channel);