[LU-9717] kernel update [RHEL7.3 3.10.0-514.26.1.el7]

• Type: Bug
• Resolution: Won't Do
• Priority: Minor
• Severity: 3
• Assignee: Bob Glossman (Inactive)
• Reporter: Bob Glossman (Inactive)

Description

Security Fix(es):

• A flaw was found in the way Linux kernel allocates heap memory to build the
  scattergather list from a fragment list(skb_shinfo(skb)->frag_list) in
  the socket buffer(skb_buff). The heap overflow occurred if 'MAX_SKB_FRAGS + 1'
  parameter and 'NETIF_F_FRAGLIST' feature were used together. A
  remote user or process could use this flaw to potentially escalate their
  privilege on a system. (CVE-2017-7477, Important)

• The NFS2/3 RPC client could send long arguments to the NFS server. These
  encoded arguments are stored in an array of memory pages, and accessed using
  pointer variables. Arbitrarily long arguments could make these pointers point
  outside the array and cause an out-of-bounds memory access. A remote user or
  program could use this flaw to crash the kernel (denial of service).
  (CVE-2017-7645, Important)

• The NFSv2 and NFSv3 server implementations in the Linux kernel through 4.10.13
  lacked certain checks for the end of a buffer. A remote attacker could trigger a
  pointer-arithmetic error or possibly cause other unspecified impacts using
  crafted requests related to fs/nfsd/nfs3xdr.c and fs/nfsd/nfsxdr.c.
  (CVE-2017-7895, Important)

• The Linux kernel built with the Kernel-based Virtual Machine (CONFIG_KVM)
  support was vulnerable to an incorrect segment selector(SS) value error. The
  error could occur while loading values into the SS register in long mode. A user
  or process inside a guest could use this flaw to crash the guest, resulting in
  DoS or potentially escalate their privileges inside the guest. (CVE-2017-2583,
  Moderate)

• A flaw was found in the Linux kernel's handling of packets with the URG flag.
  Applications using the splice() and tcp_splice_read() functionality could allow
  a remote attacker to force the kernel to enter a condition in which it could
  loop indefinitely. (CVE-2017-6214, Moderate)

Bug Fix(es):

• Previously, the reserved-pages counter (HugePages_Rsvd) was bigger than the
  total-pages counter (HugePages_Total) in the /proc/meminfo file, and
  HugePages_Rsvd underflowed. With this update, the HugeTLB feature of the Linux
  kernel has been fixed, and HugePages_Rsvd underflow no longer occurs.
  (BZ#1445184)

• If a directory on a NFS client was modified while being listed, the NFS client
  could restart the directory listing multiple times. Consequently, the
  performance of listing the directory was sub-optimal. With this update, the
  restarting of the directory listing happens less frequently. As a result, the
  performance of listing the directory while it is being modified has improved.
  (BZ#1450851)

• The Fibre Channel over Ethernet (FCoE) adapter in some cases failed to reboot.
  This update fixes the qla2xxx driver, and FCoE adapter now reboots as expected.
  (BZ#1446246)

• When a VM with Virtual Function I/O (VFIO) device was rebooted, the QEMU
  process occasionally terminated unexpectedly due to a failed VFIO Direct Memory
  Access (DMA) map request. This update fixes the vfio driver and QEMU no longer
  crashes in the described situation. (BZ#1450855)

• When the operating system was booted with the in-box lpfc driver, a kernel
  panic occurred on the little-endian variant of IBM Power Systems. This update
  fixes lpfc, and the kernel no longer panics in the described situation.
  (BZ#1452044)

• When creating or destroying a VM with Virtual Function I/O (VFIO) devices with
  "Hugepages" feature enabled, errors in Direct Memory Access (DMA) page table
  entry (PTE) mappings occurred, and QEMU memory usage behaved unpredictably. This
  update fixes range computation when making room for large pages in Input/Output
  Memory Management Unit (IOMMU). As a result, errors in DMA PTE mappings no
  longer occur, and QEMU has a predictable memory usage in the described
  situation. (BZ#1450856)

Bugs fixed (https://bugzilla.redhat.com/):

1414735 - CVE-2017-2583 Kernel: Kvm: vmx/svm potential privilege escalation inside guest
1426542 - CVE-2017-6214 kernel: ipv4/tcp: Infinite loop in tcp_splice_read()
1443615 - CVE-2017-7645 kernel: nfsd: Incorrect handling of long RPC replies
1445207 - CVE-2017-7477 kernel: net: Heap overflow in skb_to_sgvec in macsec.c
1446103 - CVE-2017-7895 kernel: NFSv3 server does not properly handle payload bounds checking of WRITE requests

Issue Links

• is related to: LU-9738 kernel update [RHEL7.3 3.10.0-514.26.2.el7]
• is related to: LU-9686 kernel update [RHEL7.3 3.10.0-514.21.2.el7]