[Bug 1791220] Re: increased crash rate since 10.3 upgrade is available

[Launchpad Bug Tracker]

** Merge proposal linked:
   https://code.launchpad.net/~paelzer/ubuntu/+source/open-vm-tools/+git/open-vm-tools/+merge/354555

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to systemd in Ubuntu.
https://bugs.launchpad.net/bugs/1791220

Title:
  increased crash rate since 10.3 upgrade is available

Status in VMWare tools:
  Unknown
Status in open-vm-tools package in Ubuntu:
  New
Status in systemd package in Ubuntu:
  New

Bug description:
  [Impact]

   * The new version of open-vm-tools we recently SRUed had an issue
     that if started in non-VMWare environments (protected by systemd 
     condition-virtualization, but people fake VMware envs) would segfault.

   * It is fine to "not work there" but segfaulting is too hard

   * Upstream realized the issue, this is backporting the fix

  [Test Case]

   * Use a non-VMWare guest (e.g. a test system lxd container) and run
      $ vmtoolsd

   * This will segfault, with the fix it will have a clean exit.

  [Regression Potential]

   * All of this only affects non-VMWare environments in a tool only needed 
     in those environments - so the risk should be low. It is closing a 
     corner case of faked environments to keep bug reports and crashes down.
     I can think of a regression if the detection of the VMContext would be 
     wrong and therefore the service not properly initializing anymore in 
     systems it should do so - so far such an issue was not seen, btu that 
     would be the most likely potential regression.

  [Other Info]
   
   * n/a

  
  ---

  Hi,

  Crash reports like:
  vmtoolsd (11) /usr/lib/libvmtools.so.0.0.0+2839c → [stack]+1ecfc → /usr/lib/libvmtools.so.0.0.0+4eb05 → /usr/lib/open-vm-tools/plugins/common/libhgfsServer.so+ccf → /usr/bin/vmtoolsd+5e98 → /usr/bin/vmtoolsd+4ce3 → /usr/bin/vmtoolsd+3ea8

  The cmdline of the failing process had:
  /usr/bin/vmtoolsd -n vmusr --blockFd 3

  I have a disassembly thou which looks like:

  => 0x7fedb35b739c <Backdoor_InOut+28>:	in (%dx),%eax
  0x7fedb35b739d <Backdoor_InOut+29>:	xchg %rax,(%rsp)
  0x7fedb35b73a1 <Backdoor_InOut+33>:	mov %rdi,0x28(%rax)
  0x7fedb35b73a5 <Backdoor_InOut+37>:	mov %rsi,0x20(%rax)
  0x7fedb35b73a9 <Backdoor_InOut+41>:	mov %rdx,0x18(%rax)
  0x7fedb35b73ad <Backdoor_InOut+45>:	mov %rcx,0x10(%rax)
  0x7fedb35b73b1 <Backdoor_InOut+49>:	mov %rbx,0x8(%rax)
  0x7fedb35b73b5 <Backdoor_InOut+53>:	popq (%rax)
  0x7fedb35b73b7 <Backdoor_InOut+55>:	pop %rbx
  0x7fedb35b73b8 <Backdoor_InOut+56>:	retq
  0x7fedb35b73b9:	nopl 0x0(%rax)
  0x7fedb35b73c0 <BackdoorHbIn>:	push %rbx
  0x7fedb35b73c1 <BackdoorHbIn+1>:	mov %rdi,%rax
  0x7fedb35b73c4 <BackdoorHbIn+4>:	push %rbp
  0x7fedb35b73c5 <BackdoorHbIn+5>:	push %rax
  0x7fedb35b73c6 <BackdoorHbIn+6>:	mov 0x30(%rax),%rbp

  We don't have much more yet.
  I filed an issue upstream [2] last week in case this showed up somewhere else as well, but haven't seen any response yet.

  Crash reports overview (might need ubuntu signin) are at [3] and one
  example is [4]

  [1]: https://bugs.launchpad.net/ubuntu/+source/open-vm-tools/+bug/1784638
  [2]: https://github.com/vmware/open-vm-tools/issues/284
  [3]: https://errors.ubuntu.com/?release=Ubuntu%2018.04&package=open-vm-tools&period=week&version=2%3A10.3.0-0ubuntu1~18.04.1
  [4]: https://errors.ubuntu.com/problem/bff98ff07d389a1a92b6cd538a823c1e2ce1a193

To manage notifications about this bug go to:
https://bugs.launchpad.net/open-vm-tools/+bug/1791220/+subscriptions