CVE ID:	CVE-2021-26930
Description:	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.
Test IDs:	1.3.6.1.4.1.25623.1.0.892610
Cross References:	Common Vulnerability Exposure (CVE) ID: CVE-2021-26930 https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/GWQWPWYZRXVFJI5M3VCM72X27IB7CKOB/ https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/2XQR52ICKRK3GC4HDWLMWF2U55YGAR63/ http://xenbits.xen.org/xsa/advisory-365.html https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=871997bc9e423f05c7da7c9178e62dde5df2a7f8 https://lists.debian.org/debian-lts-announce/2021/03/msg00010.html https://lists.debian.org/debian-lts-announce/2021/03/msg00035.html