kernel/linux.git/tools/testing/selftests/kvm/kvm_binary_stats_test.c, branch v6.6.132

KVM: selftests: Verify stats fd is usable after VM fd has been closed

2023-07-29T15:05:30+00:00

Verify that VM and vCPU binary stats files are usable even after userspace has put its last direct reference to the VM. This is a regression test for a UAF bug where KVM didn't gift the stats files a reference to the VM. Signed-off-by: Sean Christopherson Message-Id: <20230711230131.648752-8-seanjc@google.com> Signed-off-by: Paolo Bonzini

KVM: selftests: Verify stats fd can be dup()'d and read

2023-07-29T15:05:30+00:00

Expand the binary stats test to verify that a stats fd can be dup()'d and read, to (very) roughly simulate userspace passing around the file. Adding the dup() test is primarily an intermediate step towards verifying that userspace can read VM/vCPU stats before _and_ after userspace closes its copy of the VM fd; the dup() test itself is only mildly interesting. Signed-off-by: Sean Christopherson Message-Id: <20230711230131.648752-7-seanjc@google.com> Signed-off-by: Paolo Bonzini

KVM: selftests: Verify userspace can create "redundant" binary stats files

2023-07-29T15:05:30+00:00

Verify that KVM doesn't artificially limit KVM_GET_STATS_FD to a single file per VM/vCPU. There's no known use case for getting multiple stats fds, but it should work, and more importantly creating multiple files will make it easier to test that KVM correct manages VM refcounts for stats files. Signed-off-by: Sean Christopherson Message-Id: <20230711230131.648752-6-seanjc@google.com> Signed-off-by: Paolo Bonzini

KVM: selftests: Explicitly free vcpus array in binary stats test

2023-07-29T15:05:29+00:00

Explicitly free the all-encompassing vcpus array in the binary stats test so that the test is consistent with respect to freeing all dynamically allocated resources (versus letting them be freed on exit). Signed-off-by: Sean Christopherson Message-Id: <20230711230131.648752-5-seanjc@google.com> Signed-off-by: Paolo Bonzini

KVM: selftests: Clean up stats fd in common stats_test() helper

2023-07-29T15:05:29+00:00

Move the stats fd cleanup code into stats_test() and drop the superfluous vm_stats_test() and vcpu_stats_test() helpers in order to decouple creation of the stats file from consuming/testing the file (deduping code is a bonus). This will make it easier to test various edge cases related to stats, e.g. that userspace can dup() a stats fd, that userspace can have multiple stats files for a singleVM/vCPU, etc. Signed-off-by: Sean Christopherson Message-Id: <20230711230131.648752-4-seanjc@google.com> Signed-off-by: Paolo Bonzini

KVM: selftests: Use pread() to read binary stats header

2023-07-29T15:05:28+00:00

Use pread() with an explicit offset when reading the header and the header name for a binary stats fd so that the common helper and the binary stats test don't subtly rely on the file effectively being untouched, e.g. to allow multiple reads of the header, name, etc. Signed-off-by: Sean Christopherson Message-Id: <20230711230131.648752-3-seanjc@google.com> Signed-off-by: Paolo Bonzini

KVM: selftests: Stop assuming stats are contiguous in kvm_binary_stats_test

2023-01-24T18:06:34+00:00

Remove the assumption from kvm_binary_stats_test that all stats are laid out contiguously in memory. The current stats in KVM are contiguously laid out in memory, but that may change in the future and the ABI specifically allows holes in the stats data (since each stat exposes its own offset). While here drop the check that each stats' offset is less than size_data, as that is now always true by construction. Link: https://lore.kernel.org/kvm/20221208193857.4090582-9-dmatlack@google.com/ Fixes: 0b45d58738cd ("KVM: selftests: Add selftest for KVM statistics data binary interface") Signed-off-by: Jing Zhang [dmatlack: Re-worded the commit message.] Signed-off-by: David Matlack Link: https://lore.kernel.org/r/20230117222707.3949974-1-dmatlack@google.com Signed-off-by: Sean Christopherson

KVM: selftests: Use TAP interface in the kvm_binary_stats_test

2022-12-29T20:33:14+00:00

The kvm_binary_stats_test test currently does not have any output (unless one of the TEST_ASSERT statement fails), so it's hard to say for a user how far it did proceed already. Thus let's make this a little bit more user-friendly and include some TAP output via the kselftest.h interface. Signed-off-by: Thomas Huth Reviewed-by: Andrew Jones Message-Id: <20221004093131.40392-2-thuth@redhat.com> Signed-off-by: Paolo Bonzini

selftests: KVM: Add exponent check for boolean stats

2022-08-01T12:01:23+00:00

The only sensible exponent for a boolean stat is 0. Add a test assertion requiring all boolean statistics to have an exponent of 0. Signed-off-by: Oliver Upton Reviewed-by: Andrew Jones Message-Id: <20220719143134.3246798-4-oliver.upton@linux.dev> Signed-off-by: Paolo Bonzini

selftests: KVM: Provide descriptive assertions in kvm_binary_stats_test

2022-08-01T12:01:22+00:00

As it turns out, tests sometimes fail. When that is the case, packing the test assertion with as much relevant information helps track down the problem more quickly. Sharpen up the stat descriptor assertions in kvm_binary_stats_test to more precisely describe the reason for the test assertion and which stat is to blame. Signed-off-by: Oliver Upton Reviewed-by: Andrew Jones Message-Id: <20220719143134.3246798-3-oliver.upton@linux.dev> Signed-off-by: Paolo Bonzini