diff options
| author | Vincent Donnefort <vdonnefort@google.com> | 2026-05-14 17:26:24 +0100 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2026-05-20 08:08:37 +0100 |
| commit | 1702da76e017ae0fbe1a92b07bc332972c293e89 (patch) | |
| tree | a13a36048f57d8cb87f0bc2c2f177ce41055112c | |
| parent | f19c354dbd457759dfcf1195ab4bdba2bb568323 (diff) | |
KVM: arm64: Fix nVHE/pKVM hyp tracing error on invalid desc
pKVM must validate the host-provided tracing buffer descriptor.
However, if an error is found, the hypervisor would just return 0 to the
host. Fix the return value on validation failure.
While at it, rename the function to hyp_trace_desc_is_valid() and skip
validation for the nVHE mode as we trust host-provided data in that
case.
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Fixes: 680a04c333fa ("KVM: arm64: Add tracing capability for the nVHE/pKVM hyp")
Link: https://lore.kernel.org/r/20260514162624.3477857-1-vdonnefort@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/trace.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/arch/arm64/kvm/hyp/nvhe/trace.c b/arch/arm64/kvm/hyp/nvhe/trace.c index a6ca27b18e15..e7e150ab265f 100644 --- a/arch/arm64/kvm/hyp/nvhe/trace.c +++ b/arch/arm64/kvm/hyp/nvhe/trace.c @@ -164,13 +164,16 @@ static int hyp_trace_buffer_load(struct hyp_trace_buffer *trace_buffer, return ret; } -static bool hyp_trace_desc_validate(struct hyp_trace_desc *desc, size_t desc_size) +static bool hyp_trace_desc_is_valid(struct hyp_trace_desc *desc, size_t desc_size) { struct ring_buffer_desc *rb_desc; unsigned int cpu; size_t nr_bpages; void *desc_end; + if (!is_protected_kvm_enabled()) + return true; + /* * Both desc_size and bpages_backing_size are untrusted host-provided * values. We rely on __pkvm_host_donate_hyp() to enforce their validity. @@ -212,8 +215,10 @@ int __tracing_load(unsigned long desc_hva, size_t desc_size) if (ret) return ret; - if (!hyp_trace_desc_validate(desc, desc_size)) + if (!hyp_trace_desc_is_valid(desc, desc_size)) { + ret = -EINVAL; goto err_release_desc; + } hyp_spin_lock(&trace_buffer.lock); |