Description
In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: vgic: Handle race between interrupt affinity change and LPI disabling Hyunwoo Kim reports some really bad races should the following situation occur: - LPI-I is pending in vcpu-B's AP list - vcpu-A writes to vcpu-B's RD to disable its LPIs - vcpu-C moves I from B to C If the last two race nicely enough, vgic_prune_ap_list() can drop the irq and AP list locks, reacquire them, and in the interval the irq has been freed. UAF follows. The fix is two-fold: - Before dropping the irq and ap_list locks, take a reference on the irq - Do not try to handle migration of the pending bit: there is no expectation that this state is retained, as per the architecture With that, we're sure that the interrupt is still around, and we safely remove it from the AP list as it has no target at this stage (unless another interrupt fires, but that's another story).
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
5dd4b924e390af426e424d5e52c1b4d1566af817 to < 7328cff91703ac4e93c200b20cebaa36d2f314edaffected5dd4b924e390af426e424d5e52c1b4d1566af817 to < eb74f3feb68e64cf69f86cb806a15d8cfb6757f4affected5dd4b924e390af426e424d5e52c1b4d1566af817 to < 77c61235d66246dd6a5f55587f0afc273d832775affected5dd4b924e390af426e424d5e52c1b4d1566af817 to < d19dca8194ebed371e624331c6be2cb73b562cafaffected5dd4b924e390af426e424d5e52c1b4d1566af817 to < b1a89d12d35a8256d2b170ced0b1c86851f3def2affected5dd4b924e390af426e424d5e52c1b4d1566af817 to < 7258770e5814f15e8308ebda82ac9acf6964ba8eaffected
Linux Linux
Default version status: affected
4.8affected0 to < 4.8unaffected6.1.191 to ≤ 6.1.*unaffected6.6.160 to ≤ 6.6.*unaffected6.12.114 to ≤ 6.12.*unaffected6.18.40 to ≤ 6.18.*unaffected7.1.5 to ≤ 7.1.*unaffected7.2 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/7328cff91703ac4e93c200b20cebaa36d2f314ed ↗
- https://git.kernel.org/stable/c/eb74f3feb68e64cf69f86cb806a15d8cfb6757f4 ↗
- https://git.kernel.org/stable/c/77c61235d66246dd6a5f55587f0afc273d832775 ↗
- https://git.kernel.org/stable/c/d19dca8194ebed371e624331c6be2cb73b562caf ↗
- https://git.kernel.org/stable/c/b1a89d12d35a8256d2b170ced0b1c86851f3def2 ↗
- https://git.kernel.org/stable/c/7258770e5814f15e8308ebda82ac9acf6964ba8e ↗