Description
Since Linux kernel version 3.2, the mremap() syscall performs TLB flushes after dropping pagetable locks. If a syscall such as ftruncate() removes entries from the pagetables of a task that is in the middle of mremap(), a stale TLB entry can remain for a short time that permits access to a physical page after it has been released back to the page allocator and reused. This is fixed in the following kernel versions: 4.9.135, 4.14.78, 4.18.16, 4.19.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
n/a n/a
n/aaffected
References
- http://packetstormsecurity.com/files/150001/Linux-mremap-TLB-Flush-Too-Late.html ↗
- https://usn.ubuntu.com/3835-1/ ↗
- https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.18.16 ↗
- https://usn.ubuntu.com/3880-1/ ↗
- https://usn.ubuntu.com/3871-5/ ↗
- https://usn.ubuntu.com/3871-4/ ↗
- http://www.openwall.com/lists/oss-security/2018/10/29/5 ↗
- https://usn.ubuntu.com/3880-2/ ↗
- https://usn.ubuntu.com/3832-1/ ↗
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=eb66ae030829605d61fbef1909ce310e29f78821 ↗
- http://www.securityfocus.com/bid/105761 ↗
- https://usn.ubuntu.com/3871-1/ ↗
- https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.78 ↗
- http://www.securityfocus.com/bid/106503 ↗
- https://usn.ubuntu.com/3871-3/ ↗
- https://bugs.chromium.org/p/project-zero/issues/detail?id=1695 ↗
- https://lists.debian.org/debian-lts-announce/2019/03/msg00017.html ↗
- https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.135 ↗
- https://lists.debian.org/debian-lts-announce/2019/03/msg00034.html ↗
- https://lists.debian.org/debian-lts-announce/2019/04/msg00004.html ↗
- https://access.redhat.com/errata/RHSA-2019:0831 ↗
- https://access.redhat.com/errata/RHSA-2019:2043 ↗
- https://access.redhat.com/errata/RHSA-2019:2029 ↗
- https://access.redhat.com/errata/RHSA-2020:0036 ↗
- https://access.redhat.com/errata/RHSA-2020:0100 ↗
- https://access.redhat.com/errata/RHSA-2020:0103 ↗
- https://access.redhat.com/errata/RHSA-2020:0179 ↗