diff options
| author | Paolo Bonzini <[email protected]> | 2023-08-04 16:42:45 +0000 |
|---|---|---|
| committer | Paolo Bonzini <[email protected]> | 2023-08-04 17:33:06 +0000 |
| commit | 4e15a0ddc3ff40e8ea84032213976ecf774d7f77 (patch) | |
| tree | 950e2a1a88cb352c9ad87800dec88ab997778e32 /tools/perf/scripts/python/Perf-Trace-Util/lib/Perf/Trace/Util.py | |
| parent | KVM: selftests: Expand x86's sregs test to cover illegal CR0 values (diff) | |
| download | kernel-4e15a0ddc3ff40e8ea84032213976ecf774d7f77.tar.gz kernel-4e15a0ddc3ff40e8ea84032213976ecf774d7f77.zip | |
KVM: SEV: snapshot the GHCB before accessing it
Validation of the GHCB is susceptible to time-of-check/time-of-use vulnerabilities.
To avoid them, we would like to always snapshot the fields that are read in
sev_es_validate_vmgexit(), and not use the GHCB anymore after it returns.
This means:
- invoking sev_es_sync_from_ghcb() before any GHCB access, including before
sev_es_validate_vmgexit()
- snapshotting all fields including the valid bitmap and the sw_scratch field,
which are currently not caching anywhere.
The valid bitmap is the first thing to be copied out of the GHCB; then,
further accesses will use the copy in svm->sev_es.
Fixes: 291bd20d5d88 ("KVM: SVM: Add initial support for a VMGEXIT VMEXIT")
Cc: [email protected]
Signed-off-by: Paolo Bonzini <[email protected]>
Diffstat (limited to 'tools/perf/scripts/python/Perf-Trace-Util/lib/Perf/Trace/Util.py')
0 files changed, 0 insertions, 0 deletions