** Changed in: linux (Ubuntu Xenial)
       Status: In Progress => Fix Committed

-- 
You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux in Ubuntu.
https://bugs.launchpad.net/bugs/1847189

Title:
  Bad posix clock speculation mitigation backport

Status in linux package in Ubuntu:
  Invalid
Status in linux source package in Xenial:
  Fix Committed

Bug description:
  [Impact]

  Vitaly Nikolenko pointed out that syscall(__NR_clock_gettime, 10, 0)
  can be used to perform a denial of service (system crash) or possibly
  execute arbitrary code in the Ubuntu Xenial kernel:

    https://twitter.com/vnik5287/status/1180666151216435200

  [Test Case]

  Execute the following test program and verify that it prints out
  "clock_gettime: Invalid argument" rather than triggering a NULL
  pointer dereference and stack trace in the kernel logs.

  ==========
  #include <stdio.h>
  #include <time.h>

  int main(void)
  {
          int rc = clock_gettime(10, 0);

          if (rc < 0)
                  perror("clock_gettime");

          return rc;
  }
  ==========

  [Regression Potential]

  Low. The fix is easy to review and fixes a denial of service issue
  that's trivial to trigger.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1847189/+subscriptions

-- 
Mailing list: https://launchpad.net/~kernel-packages
Post to     : kernel-packages@lists.launchpad.net
Unsubscribe : https://launchpad.net/~kernel-packages
More help   : https://help.launchpad.net/ListHelp

Reply via email to