title: um: time-travel: fix time corruption
description: In the Linux kernel, the following vulnerability has been resolved:
um: time-travel: fix time corruption
In 'basic' time-travel mode (without =inf-cpu or =ext), we
still get timer interrupts. These can happen at arbitrary
points in time, i.e. while in timer_read(), which pushes
time forward just a little bit. Then, if we happen to get
the interrupt after calculating the new time to push to,
but before actually finishing that, the interrupt will set
the time to a value that's incompatible with the forward,
and we'll crash because time goes backwards when we do the
forwarding.
Fix this by reading the time_travel_time, calculating the
adjustment, and doing the adjustment all with interrupts
disabled.
affected:
{
product: Linux
vendor: Linux
defaultStatus: unaffected
repo: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
versions:
version: 1da177e4c3f4, lessThan: 0c7478a2da3f, status: affected, versionType: git
version: 1da177e4c3f4, lessThan: 4f7dad73df4c, status: affected, versionType: git
version: 1da177e4c3f4, lessThan: de3e9d8e8d1a, status: affected, versionType: git
version: 1da177e4c3f4, lessThan: b427f55e9d41, status: affected, versionType: git
version: 1da177e4c3f4, lessThan: abe4eaa8618b, status: affected, versionType: git
}
{
product: Linux
vendor: Linux
defaultStatus: affected
repo: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
versions:
version: 5.15.149, lessThanOrEqual: 5.15.*, status: unaffected, versionType: custom
version: 6.1.77, lessThanOrEqual: 6.1.*, status: unaffected, versionType: custom
version: 6.6.16, lessThanOrEqual: 6.6.*, status: unaffected, versionType: custom
version: 6.7.4, lessThanOrEqual: 6.7.*, status: unaffected, versionType: custom
version: 6.8, lessThanOrEqual: *, status: unaffected, versionType: original_commit_for_fix
}
