Oracle Linux: CVE-2018-1000204: ELSA-2018-4288: Unbreakable Enterprise kernel security update (IMPORTANT) (Multiple Advisories)

Linux Kernel version 3.18 to 4.16 incorrectly handles an SG_IO ioctl on /dev/sg0 with dxfer_direction=SG_DXFER_FROM_DEV and an empty 6-byte cmdp. This may lead to copying up to 1000 kernel heap pages to the userspace. This has been fixed upstream in https://github.com/torvalds/linux/commit/a45b599ad808c3c982fdcdc12b0b8611c2f92824 already. The problem has limited scope, as users don't usually have permissions to access SCSI devices. On the other hand, e.g. the Nero user manual suggests doing `chmod o+r+w /dev/sg*` to make the devices accessible. NOTE: third parties dispute the relevance of this report, noting that the requirement for an attacker to have both the CAP_SYS_ADMIN and CAP_SYS_RAWIO capabilities makes it "virtually impossible to exploit.
A malformed SG_IO ioctl issued for a SCSI device in the Linux kernel leads to a local kernel data leak manifesting in up to approximately 1000 memory pages copied to the userspace. The problem has limited scope as non-privileged users usually have no permissions to access SCSI device files.