CVSS 5.5 · Medium EPSS 0,17%
Kerentanan pada linux kernel, debian linux. Skor CVSS 3.1 5.5 (Medium) menurut NVD.
In the Linux kernel, the following vulnerability has been resolved: net/sched: Abort __tc_modify_qdisc if parent class does not exist Lion's patch [1] revealed an ancient bug in the qdisc API. Whenever a user creates/modifies a qdisc specifying as a parent another qdisc, the qdisc API will, during grafting, detect that the user is not trying to attach to a class and reject. However grafting is performed after qdisc_create (and thus the qdiscs' init callback) is executed. In qdiscs that eventually call qdisc_tree_reduce_backlog during init or change (such as fq, hhf, choke, etc), an issue arises. For example, executing the following commands: sudo tc qdisc add dev lo root handle a: htb default 2 sudo tc qdisc add dev lo parent a: handle beef fq Qdiscs such as fq, hhf, choke, etc unconditionally invoke qdisc_tree_reduce_backlog() in their control path init() or change() which then causes a failure to find the child class; however, that does not stop the unconditional invocation of the assumed child qdisc's qlen_notify with a null class. All these qdiscs make the assumption that class is non-null. The solution is ensure that qdisc_leaf() which looks up the parent class, and is invoked prior to qdisc_create(), should return failure on not finding the class. In this patch, we leverage qdisc_leaf to return ERR_PTRs whenever the parentid doesn't correspond to a class, so that we can detect it earlier on and abort before qdisc_create is called. [1] https://lore.kernel.org/netdev/d912cbd7-193b-4269-9857-525bee8bbb6a@gmail.com/
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
· uraikan di kalkulator | Vendor | Produk | Versi terdampak |
|---|---|---|
| linux | linux kernel | Versi 2.6.20 hingga sebelum 5.4.296 |
| linux | linux kernel | Versi 5.5 hingga sebelum 5.10.240 |
| linux | linux kernel | Versi 5.11 hingga sebelum 5.15.189 |
| linux | linux kernel | Versi 5.16 hingga sebelum 6.1.146 |
| linux | linux kernel | Versi 6.2 hingga sebelum 6.6.99 |
| linux | linux kernel | Versi 6.7 hingga sebelum 6.12.39 |
| linux | linux kernel | Versi 6.13 hingga sebelum 6.15.7 |
| linux | linux kernel | Versi 6.16 rc1 |
| linux | linux kernel | Versi 6.16 rc2 |
| linux | linux kernel | Versi 6.16 rc3 |
| linux | linux kernel | Versi 6.16 rc4 |
| linux | linux kernel | Versi 6.16 rc5 |
| debian | debian linux | Versi 11.0 |