An issue was discovered in xfs_setattr_nonsize in fs/xfs/xfs_iops.c in the Linux kernel. XFS partially wedges when a chgrp fails on account of being out of disk quota. xfs_setattr_nonsize is failing to unlock the ILOCK after the xfs_qm_vop_chown_reserve call fails. This is primarily a local DoS attack vector, but it might result as well in remote DoS if the XFS filesystem is exported for instance via NFS. Reference: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=1fb254aa983bf190cfd685d40c64a480a9bafaee https://github.com/torvalds/linux/commit/1fb254aa983bf190cfd685d40c64a480a9bafaee https://lore.kernel.org/linux-xfs/20190823192433.GA8736@eldamar.local https://lore.kernel.org/linux-xfs/20190823035528.GH1037422@magnolia/
Created kernel tracking bugs for this issue: Affects: fedora-all [bug 1746779]
Mitigation: Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
This issue has been addressed in the following products: Red Hat Enterprise Linux 7 Via RHSA-2020:2104 https://access.redhat.com/errata/RHSA-2020:2104
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s): https://access.redhat.com/security/cve/cve-2019-15538