2024-02-14 10:24:39

by WANG Xuerui

[permalink] [raw]
Subject: [PATCH for-6.8 2/5] KVM: LoongArch: Fix kvm_check_cpucfg incorrectly accepting bad CPUCFG IDs

From: WANG Xuerui <[email protected]>

The return value of _kvm_get_cpucfg is meant to be checked, but this
was not done, so bad CPUCFG IDs wrongly fall back to the default case
and 0 is returned.

Check the return value to fix the UAPI behavior.

While at it, also remove the redundant range check, because
_kvm_get_cpucfg already rejects all unrecognized input CPUCFG IDs.
It was also wrong and no-op, in the same way as the former identical
check in _kvm_get_cpucfg.

Fixes: db1ecca22edf ("LoongArch: KVM: Add LSX (128bit SIMD) support")
Signed-off-by: WANG Xuerui <[email protected]>
---
arch/loongarch/kvm/vcpu.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/arch/loongarch/kvm/vcpu.c b/arch/loongarch/kvm/vcpu.c
index c4a592623da6..cc2332b056ba 100644
--- a/arch/loongarch/kvm/vcpu.c
+++ b/arch/loongarch/kvm/vcpu.c
@@ -328,12 +328,10 @@ static int _kvm_get_cpucfg(int id, u64 *v)
static int kvm_check_cpucfg(int id, u64 val)
{
u64 mask;
- int ret = 0;
-
- if (id < 0 && id >= KVM_MAX_CPUCFG_REGS)
- return -EINVAL;
+ int ret;

- if (_kvm_get_cpucfg(id, &mask))
+ ret = _kvm_get_cpucfg(id, &mask);
+ if (ret)
return ret;

switch (id) {
--
2.43.0