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| author | Mostafa Saleh <smostafa@google.com> | 2026-04-30 13:37:24 +0300 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2026-05-06 19:09:48 +0300 |
| commit | 9a624ea3f26f40c76bd2c7f77cde30659d42efbd (patch) | |
| tree | e840645227a6404bcd2ae75e8ffb6540b2e413a1 | |
| parent | fc240715fc5003538ff530e3cfb985e7769b7171 (diff) | |
| download | linux-9a624ea3f26f40c76bd2c7f77cde30659d42efbd.tar.xz | |
KVM: arm64: Remove potential UB on nvhe tracing clock update
Sashiko(locally) reports possiblity of division by zero and
out-of-bounds bitwise shift in trace_clock_update().
Although the clock update is untrusted, we should at least have some
basic checks to avoid undefined behaviours.
Reviewed-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Mostafa Saleh <smostafa@google.com>
Link: https://patch.msgid.link/20260430103724.2151625-1-smostafa@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/clock.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/arm64/kvm/hyp/nvhe/clock.c b/arch/arm64/kvm/hyp/nvhe/clock.c index 32fc4313fe43..a7fc61976fd0 100644 --- a/arch/arm64/kvm/hyp/nvhe/clock.c +++ b/arch/arm64/kvm/hyp/nvhe/clock.c @@ -35,6 +35,9 @@ void trace_clock_update(u32 mult, u32 shift, u64 epoch_ns, u64 epoch_cyc) struct clock_data *clock = &trace_clock_data; u64 bank = clock->cur ^ 1; + if (!mult || shift >= 64) + return; + clock->data[bank].mult = mult; clock->data[bank].shift = shift; clock->data[bank].epoch_ns = epoch_ns; |