(RHSA-2021:2725) Important: kernel security and bug fix update

The kernel packages contain the Linux kernel, the core of any Linux operating system.

Security Fix(es):

• kernel: size_t-to-int conversion vulnerability in the filesystem layer (CVE-2021-33909)

• kernel: use-after-free in net/bluetooth/hci_event.c when destroying an hci_chan (CVE-2021-33034)

• kernel: use-after-free in show_numa_stats function (CVE-2019-20934)

• kernel: mishandles invalid descriptors in drivers/media/usb/gspca/xirlink_cit.c (CVE-2020-11668)

• kernel: use-after-free in cipso_v4_genopt in net/ipv4/cipso_ipv4.c (CVE-2021-33033)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Bug Fix(es):

• [RHEL7.9.z] n_tty_open: “BUG: unable to handle kernel paging request” (BZ#1872778)

• [ESXi][RHEL7.8]“qp_alloc_hypercall result = -20” / “Could not attach to queue pair with -20” with vSphere Fault Tolerance enabled (BZ#1892237)

• [RHEL7.9][s390x][Regression] Sino Nomine swapgen IBM z/VM emulated DASD with DIAG driver returns EOPNOTSUPP (BZ#1910395)

• False-positive hard lockup detected while processing the thread state information (SysRq-T) (BZ#1912221)

• RHEL7.9 zstream - s390x LPAR with NVMe SSD will panic when it has 32 or more IFL (pci) (BZ#1917943)

• The NMI watchdog detected a hard lockup while printing RCU CPU stall warning messages to the serial console (BZ#1924688)

• nvme hangs when trying to allocate reserved tag (BZ#1926825)

• [REGRESSION] “call into AER handling regardless of severity” triggers do_recovery() unnecessarily on correctable PCIe errors (BZ#1933663)

• Module nvme_core: A double free of the kmalloc-512 cache between nvme_trans_log_temperature() and nvme_get_log_page(). (BZ#1946793)

• sctp - SCTP_CMD_TIMER_START queues active timer kernel BUG at kernel/timer.c:1000! (BZ#1953052)

• [Hyper-V][RHEL-7]When CONFIG_NET_POLL_CONTROLLER is set, mainline commit 2a7f8c3b1d3fee is needed (BZ#1953075)

• Kernel panic at cgroup_is_descendant (BZ#1957719)

• [Hyper-V][RHEL-7]Commits To Fix Kdump Failures (BZ#1957803)

• IGMPv2 JOIN packets incorrectly routed to loopback (BZ#1958339)

• [CKI kernel builds]: x86 binaries in non-x86 kernel rpms breaks systemtap [7.9.z] (BZ#1960193)

• mlx4: Fix memory allocation in mlx4_buddy_init needed (BZ#1962406)

• incorrect assertion on pi_state->pi_mutex.wait_lock from pi_state_update_owner() (BZ#1965495)