net/sched: taprio: extend minimum interval restriction to entire cycle too
Summary
net/sched: taprio: extend minimum interval restriction to entire cycle too
Original description
The description as published by the source.
In the Linux kernel, the following vulnerability has been resolved:
net/sched: taprio: extend minimum interval restriction to entire cycle too
It is possible for syzbot to side-step the restriction imposed by the
blamed commit in the Fixes: tag, because the taprio UAPI permits a
cycle-time different from (and potentially shorter than) the sum of
entry intervals.
We need one more restriction, which is that the cycle time itself must
be larger than N * ETH_ZLEN bit times, where N is the number of schedule
entries. This restriction needs to apply regardless of whether the cycle
time came from the user or was the implicit, auto-calculated value, so
we move the existing "cycle == 0" check outside the "if "(!new->cycle_time)"
branch. This way covers both conditions and scenarios.
Add a selftest which illustrates the issue triggered by syzbot.
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2024-36244 linux
- Ubuntu UBUNTU-CVE-2024-36244 linux-hwe-edge
References
- advisory github.com
- advisory nvd.nist.gov
- package git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web lists.debian.org