Use After Free Affecting kernel-rt-trace-devel package, versions *

Note: Versions mentioned in the description apply only to the upstream kernel-rt-trace-devel package and not the kernel-rt-trace-devel package as distributed by Centos. See How to fix? for Centos:7 relevant fixed versions and status.

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.

• https://access.redhat.com/security/cve/CVE-2021-47060
• https://git.kernel.org/stable/c/168e82f640ed1891a700bdb43e37da354b2ab63c
• https://git.kernel.org/stable/c/2a20592baff59c5351c5200ec667e1a2aa22af85
• https://git.kernel.org/stable/c/50cbad42bfea8c052b7ca590bd4126cdc898713c
• https://git.kernel.org/stable/c/5d3c4c79384af06e3c8e25b7770b6247496b4417
• https://git.kernel.org/stable/c/7d1bc32d6477ff96a32695ea4be8144e4513ab2d