NetSight
IP …
medium5.5

CVE-2024-36244

In the Linux kernel, the following vulnerability has been resolved: net/sched: taprio: extend minimum interval restriction to entire cycle too It is possible f…

Impact

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 products

VendorProductAffected versions
LinuxLinux Kernel
from 5.4.68 before 5.5
from 5.8.12 before 5.9
from 5.9.1 before 6.1.119
from 6.2 before 6.6.33
from 6.7 before 6.9.4
Version 5.9

References