Messages in this thread | | | From | Schspa Shi <> | Subject | Re: [PATCH] KVM: arm64: Fix 64 bit mmio handle | Date | Fri, 01 Jul 2022 22:22:51 +0800 |
| |
Marc Zyngier <maz@kernel.org> writes:
>> >> I have running some static code analysis software upon Kernel >> code. >> Seeing there is possible overflow. >> >> maks << 1U << ((len * 8) -1); >> >> The AI don't know, len is only the value of 1, 2, 4, and make >> this >> a warnings >> >> I tring to analysis this, but didn't realize the real scenario >> of >> sign extension, and finally sent this problematic patch. >> >> I do see some uninitialized memory reads (the values are not >> used >> in the end, just as temporary space for API execution), >> do we need to fix these? > > You need to be more descriptive here. What uninitialised reads? > In > general, pointing at the code and providing a full description > of what > you think is incorrect would really help... > > M. One example is int vgic_v3_has_attr_regs(struct kvm_device *dev, struct kvm_device_attr *attr) { ... case KVM_DEV_ARM_VGIC_GRP_CPU_SYSREGS: { u64 reg, id;
id = (attr->attr & KVM_DEV_ARM_VGIC_SYSREG_INSTR_MASK); return vgic_v3_has_cpu_sysregs_attr(vcpu, 0, id, ®); }
}
The funcion vgic_v3_has_cpu_sysregs_attr will read reg's value to params without initialization. There should have no problems, because the register value never used.
-- BRs Schspa Shi
| |