CVE-2020-35508

A flaw possibility of race condition and incorrect initialization of the process id was found in the Linux kernel child/parent process identification handling while filtering signal handlers. A local attacker is able to abuse this flaw to bypass checks to send any signal to a privileged process.

A flaw possibility of race condition and incorrect initialization of the process id was found in the Linux kernel child/parent process identification handling while filtering signal handlers. A local attacker is able to abuse this flaw to bypass checks to send any signal to a privileged process.

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

Security Fix(es):

• kernel: Integer overflow in Intel(R) Graphics Drivers (CVE-2020-12362)

• kernel: memory leak in sof_set_get_large_ctrl_data() function in sound/soc/sof/ipc.c (CVE-2019-18811)

• kernel: use-after-free caused by a malicious USB device in the drivers/usb/misc/adutux.c driver (CVE-2019-19523)

• kernel: use-after-free bug caused by a malicious USB device in the drivers/usb/misc/iowarrior.c driver (CVE-2019-19528)

• kernel: possible out of bounds write in kbd_keycode of keyboard.c (CVE-2020-0431)

• kernel: DoS by corrupting mountpoint reference counter (CVE-2020-12114)

• kernel: use-after-free in usb_sg_cancel function in drivers/usb/core/message.c (CVE-2020-12464)

• kernel: buffer uses out of index in ext3/4 filesystem (CVE-2020-14314)

• kernel: Use After Free vulnerability in cgroup BPF component (CVE-2020-14356)

• kernel: NULL pointer dereference in serial8250_isa_init_ports function in drivers/tty/serial/8250/8250_core.c (CVE-2020-15437)

• kernel: umask not applied on filesystem without ACL support (CVE-2020-24394)

• kernel: TOCTOU mismatch in the NFS client code (CVE-2020-25212)

• kernel: incomplete permission checking for access to rbd devices (CVE-2020-25284)

• kernel: race condition between hugetlb sysctl handlers in mm/hugetlb.c (CVE-2020-25285)

• kernel: improper input validation in ppp_cp_parse_cr function leads to memory corruption and read overflow (CVE-2020-25643)

• kernel: perf_event_parse_addr_filter memory (CVE-2020-25704)

• kernel: use-after-free in kernel midi subsystem (CVE-2020-27786)

• kernel: child process is able to access parent mm through hfi dev file handle (CVE-2020-27835)

• kernel: slab-out-of-bounds read in fbcon (CVE-2020-28974)

• kernel: fork: fix copy_process(CLONE_PARENT) race with the exiting ->real_parent (CVE-2020-35508)

• kernel: fuse: fuse_do_getattr() calls make_bad_inode() in inappropriate situations (CVE-2020-36322)

• kernel: use after free in tun_get_user of tun.c could lead to local escalation of privilege (CVE-2021-0342)

• kernel: NULL pointer dereferences in ov511_mode_init_regs and ov518_mode_init_regs in drivers/media/usb/gspca/ov519.c (CVE-2020-11608)

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.

Additional Changes:

For detailed information on changes in this release, see the AlmaLinux Release Notes linked from the References section.

It was discovered that the console keyboard driver in the Linux kernel contained a race condition. A local attacker could use this to expose sensitive information (kernel memory). (CVE-2020-25656)

Minh Yuan discovered that the tty driver in the Linux kernel contained race conditions when handling fonts. A local attacker could possibly use this to expose sensitive information (kernel memory). (CVE-2020-25668)

Bodong Zhao discovered a use-after-free in the Sun keyboard driver implementation in the Linux kernel. A local attacker could use this to cause a denial of service or possibly execute arbitrary code. (CVE-2020-25669)

Kiyin (尹亮) discovered that the perf subsystem in the Linux kernel did not properly deallocate memory in some situations. A privileged attacker could use this to cause a denial of service (kernel memory exhaustion). (CVE-2020-25704)

Julien Grall discovered that the Xen dom0 event handler in the Linux kernel did not properly limit the number of events queued. An attacker in a guest VM could use this to cause a denial of service in the host OS. (CVE-2020-27673)

Jinoh Kang discovered that the Xen event channel infrastructure in the Linux kernel contained a race condition. An attacker in guest could possibly use this to cause a denial of service (dom0 crash). (CVE-2020-27675)

Daniel Axtens discovered that PowerPC RTAS implementation in the Linux kernel did not properly restrict memory accesses in some situations. A privileged local attacker could use this to arbitrarily modify kernel memory, potentially bypassing kernel lockdown restrictions. (CVE-2020-27777)

It was discovered that the jfs file system implementation in the Linux kernel contained an out-of-bounds read vulnerability. A local attacker could use this to possibly cause a denial of service (system crash). (CVE-2020-27815)

Shisong Qin and Bodong Zhao discovered that Speakup screen reader driver in the Linux kernel did not correctly handle setting line discipline in some situations. A local attacker could use this to cause a denial of service (system crash). (CVE-2020-27830, CVE-2020-28941)

It was discovered that a use-after-free vulnerability existed in the infiniband hfi1 device driver in the Linux kernel. A local attacker could possibly use this to cause a denial of service (system crash). (CVE-2020-27835)

It was discovered that an information leak existed in the syscall implementation in the Linux kernel on 32 bit systems. A local attacker could use this to expose sensitive information (kernel memory). (CVE-2020-28588)

Minh Yuan discovered that the framebuffer console driver in the Linux kernel did not properly handle fonts in some conditions. A local attacker could use this to cause a denial of service (system crash) or possibly expose sensitive information (kernel memory). (CVE-2020-28974)

Michael Kurth and Pawel Wieczorkiewicz discovered that the Xen event processing backend in the Linux kernel did not properly limit the number of events queued. An attacker in a guest VM could use this to cause a denial of service in the host OS. (CVE-2020-29568)

Olivier Benjamin and Pawel Wieczorkiewicz discovered a race condition the Xen paravirt block backend in the Linux kernel, leading to a use-after-free vulnerability. An attacker in a guest VM could use this to cause a denial of service in the host OS. (CVE-2020-29569)

Jann Horn discovered that the tty subsystem of the Linux kernel did not use consistent locking in some situations, leading to a read-after-free vulnerability. A local attacker could use this to cause a denial of service (system crash) or possibly expose sensitive information (kernel memory). (CVE-2020-29660)

Jann Horn discovered a race condition in the tty subsystem of the Linux kernel in the locking for the TIOCSPGRP ioctl(), leading to a use-after- free vulnerability. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2020-29661)

It was discovered that a…

Daniele Antonioli, Nils Ole Tippenhauer, and Kasper Rasmussen discovered that legacy pairing and secure-connections pairing authentication in the Bluetooth protocol could allow an unauthenticated user to complete authentication without pairing credentials via adjacent access. A physically proximate attacker could use this to impersonate a previously paired Bluetooth device. (CVE-2020-10135)

Jay Shin discovered that the ext4 file system implementation in the Linux kernel did not properly handle directory access with broken indexing, leading to an out-of-bounds read vulnerability. A local attacker could use this to cause a denial of service (system crash). (CVE-2020-14314)

It was discovered that the block layer implementation in the Linux kernel did not properly perform reference counting in some situations, leading to a use-after-free vulnerability. A local attacker could use this to cause a denial of service (system crash). (CVE-2020-15436)

It was discovered that the serial port driver in the Linux kernel did not properly initialize a pointer in some situations. A local attacker could possibly use this to cause a denial of service (system crash). (CVE-2020-15437)

Andy Nguyen discovered that the Bluetooth HCI event packet parser in the Linux kernel did not properly handle event advertisements of certain sizes, leading to a heap-based buffer overflow. A physically proximate remote attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2020-24490)

It was discovered that the NFS client implementation in the Linux kernel did not properly perform bounds checking before copying security labels in some situations. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2020-25212)

It was discovered that the Rados block device (rbd) driver in the Linux kernel did not properly perform privilege checks for access to rbd devices in some situations. A local attacker could use this to map or unmap rbd block devices. (CVE-2020-25284)

It was discovered that the block layer subsystem in the Linux kernel did not properly handle zero-length requests. A local attacker could use this to cause a denial of service. (CVE-2020-25641)

It was discovered that the HDLC PPP implementation in the Linux kernel did not properly validate input in some situations. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2020-25643)

Kiyin (尹亮) discovered that the perf subsystem in the Linux kernel did not properly deallocate memory in some situations. A privileged attacker could use this to cause a denial of service (kernel memory exhaustion). (CVE-2020-25704)

It was discovered that the KVM hypervisor in the Linux kernel did not properly handle interrupts in certain situations. A local attacker in a guest VM could possibly use this to cause a denial of service (host system crash). (CVE-2020-27152)

It was discovered that the jfs file system implementation in the Linux kernel contained an out-of-bounds read vulnerability. A local attacker could use this to possibly cause a denial of service (system crash). (CVE-2020-27815)

It was discovered that an information leak existed in the syscall implementation in the Linux kernel on 32 bit systems. A local attacker could use this to expose sensitive information (kernel memory). (CVE-2020-28588)

It was discovered that the framebuffer implementation in the Linux kernel did not properly perform range checks in certain situations. A local attacker could use this to expose sensitive information (kernel memory). (CVE-2020-28915)

Jann Horn discovered a race condition in the copy-on-write implementation in the Linux kernel when handling hugepages. A local attacker could use this to gain unintended write access to read-only memory pages. (CVE-2020-29368)

Jann Horn discovered that the mmap implementation in the Linux kernel contained a race…