In the Linux kernel through 4.14.13, the rds_cmsg_atomic() function in 'net/rds/rdma.c' mishandles cases where page pinning fails or an invalid address is supplied by a user, leading to a NULL pointer dereference in rds_atomic_free_op() and thus to a system panic.
An upstream patch:
Created kernel tracking bugs for this issue:
Affects: fedora-all [bug 1533895]
This issue affects the Linux kernel packages as shipped with Red Hat Enterprise Linux 5. This is not currently planned to be addressed in future updates of the product due to its life cycle. For additional information, refer to the Red Hat Enterprise Linux Life Cycle: https://access.redhat.com/support/policy/updates/errata/.
This issue affects the versions of the Linux kernel as shipped with Red Hat Enterprise Linux 6 and Red Hat Enterprise MRG 2. Future Linux kernel updates for the respective releases may address this issue.
This issue does not affect the versions of the Linux kernel as shipped with Red Hat Enterprise Linux 7, its real-time kernel, Red Hat Enterprise Linux 7 for ARM 64 and Red Hat Enterprise Linux 7 for Power 9 LE, as a code with the flaw is not built and shipped with the products listed.
What is Red Hat Enterprise Linux 7 for ARM 64,
Red Hat Enterprise Linux 7 for Power 9 LE
The kernel package as shipped with Red Hat Enterprise Linux 7 for ARM 64 and Red Hat Enterprise Linux 7 for Power 9 LE is an updated kernel intended to support new architectures not available at the time of Red Hat Enterprise Linux 7 original shipping. The new kernel version is based on an upstream Linux kernel version 4.11. The offering is distributed with other updated packages, but most of the userspace is the standard Red Hat Enterprise Linux 7 Server RPM files.
For more information please refer to:
This issue has been addressed in the following products:
Red Hat Enterprise MRG 2
Via RHSA-2018:0470 https://access.redhat.com/errata/RHSA-2018:0470