In shiftfs, a non-upstream patch to the Linux kernel included in the Ubuntu 5.0 and 5.3 kernel series, shiftfs_btrfs_ioctl_fd_replace() installs an fd referencing a file from the lower filesystem without taking an additional reference to that file. After the btrfs ioctl completes this fd is closed, which then puts a reference to that file, leading to a refcount underflow.
The product uses, accesses, or otherwise operates on a resource after that resource has been expired, released, or revoked.
The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result.
| Link | Tags |
|---|---|
| https://usn.ubuntu.com/usn/usn-4183-1 | third party advisory |
| https://usn.ubuntu.com/usn/usn-4184-1 | third party advisory |
| https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=601a64857b3d7040ca15c39c929e6b9db3373ec1 | mailing list third party advisory patch |