Wang Yugui

**Name of the Vulnerable Software and Affected Versions** Linux kernel (affected versions not specified) **Description** The issue is related to a race condition between ordered extent completion and fiemap in the Linux kernel's btrfs component. This can lead to a failure in the fiemap call, resulting in an error. The problem occurs when the fiemap task finishes processing a file extent item and an ordered extent completes, causing the file extent item to be trimmed and a new one to be inserted. This can trigger a warning and produce a stack trace. The vulnerability can be exploited to cause a denial of service. **Recommendations** At the moment, there is no information about a newer version that contains a fix for this vulnerability.

**Name of the Vulnerable Software and Affected Versions** Linux kernel (affected versions not specified) **Description** The issue is related to a deadlock that occurs when cloning inline extents and using qgroups in the btrfs file system. This happens because when reserving metadata space for a transaction, the system may need to flush existing delalloc in case there is not enough free space. A mechanism was introduced to prevent a deadlock, but when using qgroups, a transaction also reserves metadata qgroup space, which can result in flushing delalloc and cause a deadlock. The deadlock occurs because flushing delalloc requires locking the file range in the inode's iotree, and the range was already locked at the beginning of the clone operation. **Recommendations** At the moment, there is no information about a newer version that contains a fix for this vulnerability.