+ rapidio-fix-possible-uaf-when-kfifo_alloc-fails.patch added to mm-nonmm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: rapidio: fix possible UAF when kfifo_alloc() fails
has been added to the -mm mm-nonmm-unstable branch.  Its filename is
     rapidio-fix-possible-uaf-when-kfifo_alloc-fails.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/rapidio-fix-possible-uaf-when-kfifo_alloc-fails.patch

This patch will later appear in the mm-nonmm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Wang Weiyang <wangweiyang2@huawei.com>
Subject: rapidio: fix possible UAF when kfifo_alloc() fails
Date: Wed, 23 Nov 2022 17:51:47 +0800

If kfifo_alloc() fails in mport_cdev_open(), goto err_fifo and just free
priv. But priv is still in the chdev->file_list, then list traversal
may cause UAF. This fixes the following smatch warning:

drivers/rapidio/devices/rio_mport_cdev.c:1930 mport_cdev_open() warn: '&priv->list' not removed from list

Link: https://lkml.kernel.org/r/20221123095147.52408-1-wangweiyang2@huawei.com
Fixes: e8de370188d0 ("rapidio: add mport char device driver")
Signed-off-by: Wang Weiyang <wangweiyang2@huawei.com>
Cc: Alexandre Bounine <alex.bou9@gmail.com>
Cc: Dan Carpenter <error27@gmail.com>
Cc: Jakob Koschel <jakobkoschel@gmail.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 drivers/rapidio/devices/rio_mport_cdev.c |    7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

--- a/drivers/rapidio/devices/rio_mport_cdev.c~rapidio-fix-possible-uaf-when-kfifo_alloc-fails
+++ a/drivers/rapidio/devices/rio_mport_cdev.c
@@ -1904,10 +1904,6 @@ static int mport_cdev_open(struct inode
 
 	priv->md = chdev;
 
-	mutex_lock(&chdev->file_mutex);
-	list_add_tail(&priv->list, &chdev->file_list);
-	mutex_unlock(&chdev->file_mutex);
-
 	INIT_LIST_HEAD(&priv->db_filters);
 	INIT_LIST_HEAD(&priv->pw_filters);
 	spin_lock_init(&priv->fifo_lock);
@@ -1926,6 +1922,9 @@ static int mport_cdev_open(struct inode
 	spin_lock_init(&priv->req_lock);
 	mutex_init(&priv->dma_lock);
 #endif
+	mutex_lock(&chdev->file_mutex);
+	list_add_tail(&priv->list, &chdev->file_list);
+	mutex_unlock(&chdev->file_mutex);
 
 	filp->private_data = priv;
 	goto out;
_

Patches currently in -mm which might be from wangweiyang2@huawei.com are

rapidio-fix-possible-uaf-when-kfifo_alloc-fails.patch