CVE-2021-47060
In the Linux kernel, the following vulnerability has been resolved: KVM: Stop looking for coalesced MMIO zones if the bus is destroyed Abort the walk of coalesced MMIO zones if kvm_io_bus_unregister_dev() fails to allocate memory for the new instance of…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.24%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
In the Linux kernel, the following vulnerability has been resolved: KVM: Stop looking for coalesced MMIO zones if the bus is destroyed Abort the walk of coalesced MMIO zones if kvm_io_bus_unregister_dev() fails to allocate memory for the new instance of the bus. If it can't instantiate a new bus, unregister_dev() destroys all devices _except_ the target device. But, it doesn't tell the caller that it obliterated the bus and invoked the destructor for all devices that were on the bus. In the coalesced MMIO case, this can result in a deleted list entry dereference due to attempting to continue iterating on coalesced_zones after future entries (in the walk) have been deleted. Opportunistically add curly braces to the for-loop, which encompasses many lines but sneaks by without braces due to the guts being a single if statement.
- CVSS 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.24% probability · 15th percentile
- CISA KEV
- Not listed
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/168e82f640ed1891a700bdb43e37da354b2ab63cPatch
- https://git.kernel.org/stable/c/2a20592baff59c5351c5200ec667e1a2aa22af85Patch
- https://git.kernel.org/stable/c/50cbad42bfea8c052b7ca590bd4126cdc898713cPatch
- https://git.kernel.org/stable/c/5d3c4c79384af06e3c8e25b7770b6247496b4417Patch
- https://git.kernel.org/stable/c/7d1bc32d6477ff96a32695ea4be8144e4513ab2dPatch
- https://git.kernel.org/stable/c/168e82f640ed1891a700bdb43e37da354b2ab63cPatch
- https://git.kernel.org/stable/c/2a20592baff59c5351c5200ec667e1a2aa22af85Patch
- https://git.kernel.org/stable/c/50cbad42bfea8c052b7ca590bd4126cdc898713cPatch
- https://git.kernel.org/stable/c/5d3c4c79384af06e3c8e25b7770b6247496b4417Patch
- https://git.kernel.org/stable/c/7d1bc32d6477ff96a32695ea4be8144e4513ab2dPatch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.