Описание
In the Linux kernel, the following vulnerability has been resolved:
iommufd: Fix race during abort for file descriptors
fput() doesn't actually call file_operations release() synchronously, it puts the file on a work queue and it will be released eventually.
This is normally fine, except for iommufd the file and the iommufd_object are tied to gether. The file has the object as it's private_data and holds a users refcount, while the object is expected to remain alive as long as the file is.
When the allocation of a new object aborts before installing the file it will fput() the file and then go on to immediately kfree() the obj. This causes a UAF once the workqueue completes the fput() and tries to decrement the users refcount.
Fix this by putting the core code in charge of the file lifetime, and call __fput_sync() during abort to ensure that release() is called before kfree. __fput_sync() is a bit too tricky to open code in all the object implementations. Instead the objects tell
Уязвимые конфигурации
Одно из
EPSS
4.7 Medium
CVSS3
Дефекты
Связанные уязвимости
In the Linux kernel, the following vulnerability has been resolved: iommufd: Fix race during abort for file descriptors fput() doesn't actually call file_operations release() synchronously, it puts the file on a work queue and it will be released eventually. This is normally fine, except for iommufd the file and the iommufd_object are tied to gether. The file has the object as it's private_data and holds a users refcount, while the object is expected to remain alive as long as the file is. When the allocation of a new object aborts before installing the file it will fput() the file and then go on to immediately kfree() the obj. This causes a UAF once the workqueue completes the fput() and tries to decrement the users refcount. Fix this by putting the core code in charge of the file lifetime, and call __fput_sync() during abort to ensure that release() is called before kfree. __fput_sync() is a bit too tricky to open code in all the object implementations. Instead the objects tell th...
In the Linux kernel, the following vulnerability has been resolved: i ...
In the Linux kernel, the following vulnerability has been resolved: iommufd: Fix race during abort for file descriptors fput() doesn't actually call file_operations release() synchronously, it puts the file on a work queue and it will be released eventually. This is normally fine, except for iommufd the file and the iommufd_object are tied to gether. The file has the object as it's private_data and holds a users refcount, while the object is expected to remain alive as long as the file is. When the allocation of a new object aborts before installing the file it will fput() the file and then go on to immediately kfree() the obj. This causes a UAF once the workqueue completes the fput() and tries to decrement the users refcount. Fix this by putting the core code in charge of the file lifetime, and call __fput_sync() during abort to ensure that release() is called before kfree. __fput_sync() is a bit too tricky to open code in all the object implementations. Instead the objects te...
EPSS
4.7 Medium
CVSS3