CVE-2018-18281
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.
| Software | From | Fixed in |
|---|---|---|
| linux / linux_kernel | 4.9.136 | 4.14.78 |
| linux / linux_kernel | 3.2 | 4.9.135 |
| linux / linux_kernel | 4.18.17 | 4.19 |
| linux / linux_kernel | 4.14.79 | 4.18.16 |
| canonical / ubuntu_linux | 16.04 | 16.04.x |
| canonical / ubuntu_linux | 14.04 | 14.04.x |
| canonical / ubuntu_linux | 12.04 | 12.04.x |
| canonical / ubuntu_linux | 18.04 | 18.04.x |
| canonical / ubuntu_linux | 18.10 | 18.10.x |
| debian / debian_linux | 8.0 | 8.0.x |
- http://packetstormsecurity.com/files/150001/Linux-mremap-TLB-Flush-Too-Late.html
- http://www.openwall.com/lists/oss-security/2018/10/29/5
- http://www.securityfocus.com/bid/105761
- http://www.securityfocus.com/bid/106503
- https://access.redhat.com/errata/RHSA-2019:0831
- https://access.redhat.com/errata/RHSA-2019:2029
- https://access.redhat.com/errata/RHSA-2019:2043
- 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
- https://bugs.chromium.org/p/project-zero/issues/detail?id=1695
- https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.78
- https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.18.16
- https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.135
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=eb66ae030829605d61fbef1909ce310e29f78821
- https://lists.debian.org/debian-lts-announce/2019/03/msg00017.html
- https://lists.debian.org/debian-lts-announce/2019/03/msg00034.html
- https://lists.debian.org/debian-lts-announce/2019/04/msg00004.html
- https://usn.ubuntu.com/3832-1/
- https://usn.ubuntu.com/3835-1/
- https://usn.ubuntu.com/3871-1/
- https://usn.ubuntu.com/3871-3/
- https://usn.ubuntu.com/3871-4/
- https://usn.ubuntu.com/3871-5/
- https://usn.ubuntu.com/3880-1/
- https://usn.ubuntu.com/3880-2/
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