Description
In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Compute the correct max length of the in-GHCB scratch area When setting the length of the GHCB scratch area, and the area is in the GHCB shared buffer, set the effective length of the scratch area to the max possible size given the start of the guest-provided pointer, and the end of the shared buffer. The code was "fine" when first introduced, as KVM doesn't consult the length of the buffer when emulating MMIO, because the passed in @len always specifies the *max* size required. But for PSC requests, the incoming @len is just the minimum length (to process the header), and KVM needs to know the full size of the scratch area to avoid buffer overflows (spoiler alert). Opportunistically rename @len => @min_len to better reflect its role.
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
9b54e248d2644be71cb394eb85f31ad99e023a05 to < 6ca9400d36005ffdca25f80186bea781c7e1dc4caffected9b54e248d2644be71cb394eb85f31ad99e023a05 to < 9f0a9e780f02c02d025a190f1885e1d1d73b87bdaffected9b54e248d2644be71cb394eb85f31ad99e023a05 to < 6644565527c4c5f507088b1c9ddf72de47790b68affected9b54e248d2644be71cb394eb85f31ad99e023a05 to < 5867d7e202e09f037cefe77f7af4413c7c0fa088affected
Linux Linux
Default version status: affected
6.11affected0 to < 6.11unaffected6.12.93 to ≤ 6.12.*unaffected6.18.35 to ≤ 6.18.*unaffected7.0.12 to ≤ 7.0.*unaffected7.1 to ≤ *unaffected