| 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; |
| _ |
