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| author | Sean Christopherson <seanjc@google.com> | 2026-07-23 17:47:57 -0700 |
|---|---|---|
| committer | Sean Christopherson <seanjc@google.com> | 2026-07-28 13:48:46 -0700 |
| commit | e186d4e34ad515f8ec45831f4386c677b3967092 (patch) | |
| tree | afb4b84d3713f478cf33c5edc3d32e974e333d5b | |
| parent | e060b94a1cd4920165aec7a77431df2927b26fdb (diff) | |
| download | linux-next-e186d4e34ad515f8ec45831f4386c677b3967092.tar.gz linux-next-e186d4e34ad515f8ec45831f4386c677b3967092.zip | |
KVM: Harden kvm_vcpu_map() against double-mapping and thus leaking references
Now that all on-stack maps use CLASS(kvm_vcpu_map_local), i.e. now that all
maps are zero-allocated, explicitly put any existing mappings/references
when establishing a new mapping to harden against KVM bugs leaking memory,
but yell loudly as the owner of the map is still ultimately responsible for
the lifecycle of the mapping.
Suggested-by: Yosry Ahmed <yosry@kernel.org>
Link: https://patch.msgid.link/20260724004757.131420-7-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
| -rw-r--r-- | virt/kvm/kvm_main.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 2df8ee9ecf6c..e9e32686e41b 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -3118,6 +3118,9 @@ int __kvm_vcpu_map(struct kvm_vcpu *vcpu, gfn_t gfn, struct kvm_host_map *map, .pin = true, }; + if (WARN_ON_ONCE(map->hva)) + kvm_vcpu_unmap(vcpu, map); + map->pinned_page = NULL; map->page = NULL; map->hva = NULL; |