[<prev] [next>] [day] [month] [year] [list]
Date: Mon, 29 Oct 2018 16:11:34 +0100
From: Jann Horn <jannh@...gle.com>
To: oss-security@...ts.openwall.com
Subject: Linux kernel: TLB flush happens too late on mremap (CVE-2018-18281;
fixed in 4.9.135, 4.14.78, 4.18.16, 4.19)
NOTE: I have requested a CVE identifier, and I'm sending this message,
to make tracking of the fix easier; however, to avoid missing security
fixes without CVE identifiers, you should *NOT* be cherry-picking a
specific patch in response to a notification about a kernel security
bug.
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 CVE-2018-18281.
This is fixed in the following kernel versions:
4.9.135
4.14.78
4.18.16
4.19
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=eb66ae030829605d61fbef1909ce310e29f78821
https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.135
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://bugs.chromium.org/p/project-zero/issues/detail?id=1695
Powered by blists - more mailing lists
Please check out the
Open Source Software Security Wiki, which is counterpart to this
mailing list.
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
