CVE-2021-26930

About vulnerability

An issue was discovered in the Linux kernel 3.11 through 5.10.16, as used by Xen. To service requests to the PV backend, the driver maps grant references provided by the frontend. In this process, errors may be encountered. In one case, an error encountered earlier might be discarded by later processing, resulting in the caller assuming successful mapping, and hence subsequent operations trying to access space that wasn’t mapped. In another case, internal state would be insufficiently updated, preventing safe recovery from the error. This affects drivers/block/xen-blkback/blkback.c.

Affected product:

Amazon Linux 1 , Amazon Linux 2 , CentOS 6 ALT , CentOS 6 ELS , CentOS 7 ALT , CentOS 8.4 ELS , CentOS 8.5 ELS , CloudLinux 6 ELS , Debian 10 , Debian 10 cloud , Debian 9 , Endurance 6 elrepo , Endurance 7 eig 4.14 , Oracle Linux 6 , Oracle Linux 6 ELS , Oracle Linux 7 , Oracle Linux 8 , Proofpoint , Proxmox VE 5 , Proxmox VE 6 , Ubuntu 14.04 , Ubuntu 14.04 ESM , Ubuntu 16.04 , Ubuntu 16.04 ELS , Ubuntu 16.04 ESM , Ubuntu 18.04 , Ubuntu 18.04 ELS , Ubuntu 20.04 , Upstream 4.14 , Upstream 4.19 , Upstream 4.4 , Upstream 4.9

Affected packages:

kernel @ - (+62 more)

An issue was discovered in the Linux kernel 3.11 through 5.10.16, as used by Xen. To service requests to the PV backend, the driver maps grant references provided by the frontend. In this process, errors may be encountered. In one case, an error encountered earlier might be discarded by later processing, resulting in the caller assuming successful mapping, and hence subsequent operations trying to access space that wasn’t mapped. In another case, internal state would be insufficiently updated, preventing safe recovery from the error. This affects drivers/block/xen-blkback/blkback.c.