Description
In the Linux kernel, the following vulnerability has been resolved: KVM: riscv: Fix NACL hfence entry update order The SBI v3.0 specification (section 15.1.2) requires a nested HFENCE entry to be populated as follows: 1) find an unused entry with Config.Pending == 0 2) update the Page_Number and Page_Count words 3) update the Config word with Config.Pending set __kvm_riscv_nacl_hfence() writes the Config word first, so the SBI implementation (or NACL hardware) can observe a pending entry with pnum/pcount values left over from the previous use of that entry, resulting in incorrect TLB flush ranges. Write pnum and pcount first and the Config word last. Since the consumer is an external agent on coherent shared memory, use WRITE_ONCE() to stop the compiler from reordering the stores and smp_wmb() to make the parameter words globally visible before the Pending bit is set.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
d466c19cead5904d4d5d92adb2b213b411d3b849 to < d6de766d8d26d71b714f548192099112def50a9caffectedd466c19cead5904d4d5d92adb2b213b411d3b849 to < 6da466502621381fa88a6684290923d25c559266affectedd466c19cead5904d4d5d92adb2b213b411d3b849 to < b3d346838ec65fac7fd83f5dbcedd13cadfffddbaffected
Linux Linux
Default version status: affected
6.13affected0 to < 6.13unaffected6.18.55 to ≤ 6.18.*unaffected7.2.9 to ≤ 7.2.*unaffected7.3 to ≤ *unaffected