CVE-2020-27675

An issue was discovered in the Linux kernel through 5.9.1, as used with Xen through 4.14.x. drivers/xen/events/events_base.c allows event-channel removal during the event-handling loop (a race condition). This can cause a use-after-free or NULL pointer dereference, as demonstrated by a dom0 crash via events for an in-reconfiguration paravirtualized device, aka CID-073d0552ead5.

The Linux Kernel, the operating system core itself.

Security Fix(es):

A flaw was found in the Linux kernel. A use-after-free memory flaw was found in the perf subsystem allowing a local attacker with permission to monitor perf events to corrupt memory and possibly escalate privileges. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.(CVE-2020-14351)

An issue was discovered in the Linux kernel through 5.9.1, as used with Xen through 4.14.x. drivers/xen/events/events_base.c allows event-channel removal during the event-handling loop (a race condition). This can cause a use-after-free or NULL pointer dereference, as demonstrated by a dom0 crash via events for an in-reconfiguration paravirtualized device, aka CID-073d0552ead5.(CVE-2020-27675)

A flaw was found in the Linux kernel. A use-after-free was found in the way the console subsystem was using ioctls KDGKBSENT and KDSKBSENT. A local user could use this flaw to get read memory access out of bounds. The highest threat from this vulnerability is to data confidentiality.(CVE-2020-25656)

Improper access control in BlueZ may allow an unauthenticated user to potentially enable information disclosure via adjacent access.(CVE-2020-12352)

A locking issue was discovered in the tty subsystem of the Linux kernel through 5.9.13. drivers/tty/tty_jobctrl.c allows a use-after-free attack against TIOCSPGRP, aka CID-54ffccbf053b.(CVE-2020-29661)

A flaw was found in the way RTAS handled memory accesses in userspace to kernel communication. On a locked down (usually due to Secure Boot) guest system running on top of PowerVM or KVM hypervisors (pseries platform) a root like local user could use this flaw to further increase their privileges to that of a running kernel.(CVE-2020-27777)

A locking inconsistency issue was discovered in the tty subsystem of the Linux kernel through 5.9.13. drivers/tty/tty_io.c and drivers/tty/tty_jobctrl.c may allow a read-after-free attack against TIOCGSID, aka CID-c8bcd9c5be24.(CVE-2020-29660)

An issue was discovered in the Linux kernel through 5.10.1, as used with Xen through 4.14.x. The Linux kernel PV block backend expects the kernel thread handler to reset ring->xenblkd to NULL when stopped. However, the handler may not have time to run if the frontend quickly toggles between the states connect and disconnect. As a consequence, the block backend may re-use a pointer after it was freed. A misbehaving guest can trigger a dom0 crash by continuously connecting / disconnecting a block frontend. Privilege escalation and information leaks cannot be ruled out. This only affects systems with a Linux blkback.(CVE-2020-29569)

A flaw was found in the JFS filesystem code. This flaw allows a local attacker with the ability to set extended attributes to panic the system, causing memory corruption or escalating privileges. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.(CVE-2020-27815)

A vulnerability was found in Linux Kernel where in the spk_ttyio_receive_buf2() function, it would dereference spk_ttyio_synth without checking whether it is NULL or not, and may lead to a NULL-ptr deref crash.(CVE-2020-27830)

An issue was discovered in the Linux kernel through 5.9.1, as used with Xen through 4.14.x. drivers/xen/events/events_base.c allows event-channel removal during the event-handling loop (a race condition). This can cause a use-after-free or NULL pointer dereference, as demonstrated by a dom0 crash via events for an in-reconfiguration paravirtualized device, aka CID-073d0552ead5.

This update provides an upgrade to the new upstream 5.10 longterm branch, currently based on 5.10.6, adding new features and new and improved hardware support.

This update also fixes at least the following security issues:

In binder_release_work of binder.c, there is a possible use-after-free due to improper locking. This could lead to local escalation of privilege in the kernel with no additional execution privileges needed. User interaction is not needed for exploitation (CVE-2020-0423).

In various methods of hid-multitouch.c, there is a possible out of bounds write due to a missing bounds check. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation (CVE-2020-0465).

Insufficient access control in the Linux kernel driver for some Intel(R) Processors may allow an authenticated user to potentially enable information disclosure via local access (CVE-2020-8694).

A potential vulnerability in the AMD extension to Linux "hwmon" service may allow an attacker to use the Linux-based Running Average Power Limit (RAPL) interface to show various side channel attacks. In line with industry partners, AMD has updated the RAPL interface to require privileged access (CVE-2020-12912).

A use-after-free memory flaw was found in the perf subsystem allowing a local attacker with permission to monitor perf events to corrupt memory and possibly escalate privileges. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability (CVE-2020-14351).

A use-after-free was found in the way the console subsystem was using ioctls KDGKBSENT and KDSKBSENT. A local user could use this flaw to get read memory access out of bounds. The highest threat from this vulnerability is to data confidentiality (CVE-2020-25656).

Linux kernel concurrency use-after-free in vt (CVE-2020-25668).

Linux Kernel use-after-free in sunkbd_reinit (CVE-2020-25669).

A flaw memory leak in the Linux kernel performance monitoring subsystem was found in the way if using PERF_EVENT_IOC_SET_FILTER. A local user could use this flaw to starve the resources causing denial of service (CVE-2020-25704).

A flaw in the way reply ICMP packets are limited in the Linux kernel functionality was found that allows to quickly scan open UDP ports. This flaw allows an off-path remote user to effectively bypassing source port UDP randomization. The highest threat from this vulnerability is to confidentiality and possibly integrity, because software that relies on UDP source port randomization are indirectly affected as well (CVE-2020-25705).

An issue was discovered in ioapic_lazy_update_eoi in arch/x86/kvm/ioapic.c in the Linux kernel before 5.9.2. It has an infinite loop related to improper interaction between a resampler and edge triggering (CVE-2020-27152).

An issue was discovered in the Linux kernel before 5.8.15. scalar32_min_max_or in kernel/bpf/verifier.c mishandles bounds tracking during use of 64-bit values (CVE-2020-27194).

An issue was discovered in the Linux kernel through 5.9.1, as used with Xen through 4.14.x. Guest OS users can cause a denial of service (host OS hang) via a high rate of events to dom0 (CVE-2020-27673).

An issue was discovered in the Linux kernel through 5.9.1, as used with Xen through 4.14.x. drivers/xen/events/events_base.c allows event-channel removal during the event-handling loop (a race condition). This can cause a use-after-free or NULL pointer dereference, as demonstrated by a dom0 crash via events for an in-reconfiguration paravirtualized device (CVE-2020-27675).

A use-after-free flaw was found in kernel/trace/ring_buffer.c in Linux kernel (before 5.10-rc1). There was a race problem in trace_open and resize of cpu buffer running parallely on different cpus, may cause a denial of service problem (DOS). This flaw could even allow a local attacker with special user privilege to a kernel information leak threat…

This update provides an upgrade to the new upstream 5.10 longterm branch, currently based on 5.10.6, adding new features and new and improved hardware support.

This update also fixes at least the following security issues:

In binder_release_work of binder.c, there is a possible use-after-free due to improper locking. This could lead to local escalation of privilege in the kernel with no additional execution privileges needed. User interaction is not needed for exploitation (CVE-2020-0423).

In various methods of hid-multitouch.c, there is a possible out of bounds write due to a missing bounds check. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation (CVE-2020-0465).

Insufficient access control in the Linux kernel driver for some Intel(R) Processors may allow an authenticated user to potentially enable information disclosure via local access (CVE-2020-8694).

A potential vulnerability in the AMD extension to Linux "hwmon" service may allow an attacker to use the Linux-based Running Average Power Limit (RAPL) interface to show various side channel attacks. In line with industry partners, AMD has updated the RAPL interface to require privileged access (CVE-2020-12912).

A use-after-free memory flaw was found in the perf subsystem allowing a local attacker with permission to monitor perf events to corrupt memory and possibly escalate privileges. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability (CVE-2020-14351).

A use-after-free was found in the way the console subsystem was using ioctls KDGKBSENT and KDSKBSENT. A local user could use this flaw to get read memory access out of bounds. The highest threat from this vulnerability is to data confidentiality (CVE-2020-25656).

Linux kernel concurrency use-after-free in vt (CVE-2020-25668).

Linux Kernel use-after-free in sunkbd_reinit (CVE-2020-25669).

A flaw memory leak in the Linux kernel performance monitoring subsystem was found in the way if using PERF_EVENT_IOC_SET_FILTER. A local user could use this flaw to starve the resources causing denial of service (CVE-2020-25704).

A flaw in the way reply ICMP packets are limited in the Linux kernel functionality was found that allows to quickly scan open UDP ports. This flaw allows an off-path remote user to effectively bypassing source port UDP randomization. The highest threat from this vulnerability is to confidentiality and possibly integrity, because software that relies on UDP source port randomization are indirectly affected as well (CVE-2020-25705).

An issue was discovered in ioapic_lazy_update_eoi in arch/x86/kvm/ioapic.c in the Linux kernel before 5.9.2. It has an infinite loop related to improper interaction between a resampler and edge triggering (CVE-2020-27152).

An issue was discovered in the Linux kernel before 5.8.15. scalar32_min_max_or in kernel/bpf/verifier.c mishandles bounds tracking during use of 64-bit values (CVE-2020-27194).

An issue was discovered in the Linux kernel through 5.9.1, as used with Xen through 4.14.x. Guest OS users can cause a denial of service (host OS hang) via a high rate of events to dom0 (CVE-2020-27673).

An issue was discovered in the Linux kernel through 5.9.1, as used with Xen through 4.14.x. drivers/xen/events/events_base.c allows event-channel removal during the event-handling loop (a race condition). This can cause a use-after-free or NULL pointer dereference, as demonstrated by a dom0 crash via events for an in-reconfiguration paravirtualized device (CVE-2020-27675).

A use-after-free flaw was found in kernel/trace/ring_buffer.c in Linux kernel (before 5.10-rc1). There was a race problem in trace_open and resize of cpu buffer running parallely on different cpus, may cause a denial of service problem (DOS). This flaw could even allow a local attacker with special user privilege to a kernel information leak threat…

The SUSE Linux Enterprise 15 SP1 kernel was updated to receive various security and bug fixes.

The following security bugs were fixed:

• CVE-2020-25656: Fixed a concurrency use-after-free in vt_do_kdgkb_ioctl (bnc#1177766).
• CVE-2020-25285: Fixed a race condition between hugetlb sysctl handlers in mm/hugetlb.c (bnc#1176485).
• CVE-2020-0430: Fixed an OOB read in skb_headlen of /include/linux/skbuff.h (bnc#1176723).
• CVE-2020-14351: Fixed a race in the perf_mmap_close() function (bsc#1177086).
• CVE-2020-16120: Fixed a permissions issue in ovl_path_open() (bsc#1177470).
• CVE-2020-8694: Restricted energy meter to root access (bsc#1170415).
• CVE-2020-27673: Fixed an issue where rogue guests could have caused denial of service of Dom0 via high frequency events (XSA-332 bsc#1177411)
• CVE-2020-27675: Fixed a race condition in event handler which may crash dom0 (XSA-331 bsc#1177410).

The following non-security bugs were fixed:

• ALSA: bebob: potential info leak in hwdep_read() (git-fixes).
• ALSA: compress_offload: remove redundant initialization (git-fixes).
• ALSA: core: init: use DECLARE_COMPLETION_ONSTACK() macro (git-fixes).
• ALSA: core: pcm: simplify locking for timers (git-fixes).
• ALSA: core: timer: clarify operator precedence (git-fixes).
• ALSA: core: timer: remove redundant assignment (git-fixes).
• ALSA: ctl: Workaround for lockdep warning wrt card->ctl_files_rwlock (git-fixes).
• ALSA: hda - Do not register a cb func if it is registered already (git-fixes).
• ALSA: hda/realtek - Add mute Led support for HP Elitebook 845 G7 (git-fixes).
• ALSA: hda/realtek - The front Mic on a HP machine does not work (git-fixes).
• ALSA: hda/realtek: Enable audio jacks of ASUS D700SA with ALC887 (git-fixes).
• ALSA: hda: auto_parser: remove shadowed variable declaration (git-fixes).
• ALSA: hda: use semicolons rather than commas to separate statements (git-fixes).
• ALSA: mixart: Correct comment wrt obsoleted tasklet usage (git-fixes).
• ALSA: rawmidi: (cosmetic) align function parameters (git-fixes).
• ALSA: seq: oss: Avoid mutex lock for a long-time ioctl (git-fixes).
• ALSA: usb-audio: Add mixer support for Pioneer DJ DJM-250MK2 (git-fixes).
• ALSA: usb-audio: endpoint.c: fix repeated word 'there' (git-fixes).
• ALSA: usb-audio: fix spelling mistake 'Frequence' -> 'Frequency' (git-fixes).
• ASoC: qcom: lpass-cpu: fix concurrency issue (git-fixes).
• ASoC: qcom: lpass-platform: fix memory leak (git-fixes).
• ath10k: check idx validity in __ath10k_htt_rx_ring_fill_n() (git-fixes).
• ath10k: Fix the size used in a 'dma_free_coherent()' call in an error handling path (git-fixes).
• ath10k: provide survey info as accumulated data (git-fixes).
• ath6kl: prevent potential array overflow in ath6kl_add_new_sta() (git-fixes).
• ath9k: Fix potential out of bounds in ath9k_htc_txcompletion_cb() (git-fixes).
• ath9k: hif_usb: fix race condition between usb_get_urb() and usb_kill_anchored_urbs() (git-fixes).
• backlight: sky81452-backlight: Fix refcount imbalance on error (git-fixes).
• blk-mq: order adding requests to hctx->dispatch and checking SCHED_RESTART (bsc#1177750).
• block: ensure bdi->io_pages is always initialized (bsc#1177749).
• Bluetooth: MGMT: Fix not checking if BT_HS is enabled (git-fixes).
• Bluetooth: Only mark socket zapped after unlocking (git-fixes).
• bnxt: do not enable NAPI until rings are ready (networking-stable-20_09_11).
• bnxt_en: Check for zero dir entries in NVRAM (networking-stable-20_09_11).
• brcm80211: fix possible memleak in brcmf_proto_msgbuf_attach (git-fixes).
• brcmfmac: check ndev pointer (git-fixes).
• brcmsmac: fix memory leak in wlc_phy_attach_lcnphy (git-fixes).
• btrfs: check the right error variable in btrfs_del_dir_entries_in_log (bsc#1177687).
• btrfs: do not force read-only after error in drop snapshot (bsc#1176354).
• btrfs: do not set the full sync flag on the inode during page release (bsc#1177687).
• btrfs: fix incorrect updating of log root tree (bsc#1177687).
• btrfs: fix race…

The SUSE Linux Enterprise 12 SP5 kernel Azure was updated to receive various security and bugfixes.

The following security bugs were fixed:

• CVE-2020-25656: Fixed a concurrency use-after-free in vt_do_kdgkb_ioctl (bnc#1177766).
• CVE-2020-25285: Fixed a race condition between hugetlb sysctl handlers in mm/hugetlb.c (bnc#1176485).
• CVE-2020-0430: Fixed an OOB read in skb_headlen of /include/linux/skbuff.h (bnc#1176723).
• CVE-2020-14351: Fixed a race in the perf_mmap_close() function (bsc#1177086).
• CVE-2020-16120: Fixed a permissions issue in ovl_path_open() (bsc#1177470).
• CVE-2020-12351: Implemented a kABI workaround for bluetooth l2cap_ops filter addition (bsc#1177724).
• CVE-2020-12352: Fixed an information leak when processing certain AMP packets aka 'BleedingTooth' (bsc#1177725).
• CVE-2020-25212: Fixed a TOCTOU mismatch in the NFS client code (bnc#1176381).
• CVE-2020-25645: Fixed an an issue in IPsec that caused traffic between two Geneve endpoints to be unencrypted (bnc#1177511).
• CVE-2020-27673: Fixed an issue where rogue guests could have caused denial of service of Dom0 via high frequency events (XSA-332 bsc#1177411)
• CVE-2020-27675: Fixed a race condition in event handler which may crash dom0 (XSA-331 bsc#1177410).
• CVE-2020-25705: A ICMP global rate limiting side-channel was removed which could lead to e.g. the SADDNS attack (bsc#1175721)

The following non-security bugs were fixed:

• ACPI: dock: fix enum-conversion warning (git-fixes).
• ALSA: bebob: potential info leak in hwdep_read() (git-fixes).
• ALSA: compress_offload: remove redundant initialization (git-fixes).
• ALSA: core: init: use DECLARE_COMPLETION_ONSTACK() macro (git-fixes).
• ALSA: core: pcm: simplify locking for timers (git-fixes).
• ALSA: core: timer: clarify operator precedence (git-fixes).
• ALSA: core: timer: remove redundant assignment (git-fixes).
• ALSA: ctl: Workaround for lockdep warning wrt card->ctl_files_rwlock (git-fixes).
• ALSA: hda: auto_parser: remove shadowed variable declaration (git-fixes).
• ALSA: hda - Do not register a cb func if it is registered already (git-fixes).
• ALSA: hda/realtek - Add mute Led support for HP Elitebook 845 G7 (git-fixes).
• ALSA: hda/realtek: Enable audio jacks of ASUS D700SA with ALC887 (git-fixes).
• ALSA: hda/realtek - The front Mic on a HP machine does not work (git-fixes).
• ALSA: hda: use semicolons rather than commas to separate statements (git-fixes).
• ALSA: mixart: Correct comment wrt obsoleted tasklet usage (git-fixes).
• ALSA: rawmidi: (cosmetic) align function parameters (git-fixes).
• ALSA: seq: oss: Avoid mutex lock for a long-time ioctl (git-fixes).
• ALSA: usb-audio: Add mixer support for Pioneer DJ DJM-250MK2 (git-fixes).
• ALSA: usb-audio: endpoint.c: fix repeated word 'there' (git-fixes).
• ALSA: usb-audio: fix spelling mistake 'Frequence' -> 'Frequency' (git-fixes).
• amd-xgbe: Add a check for an skb in the timestamp path (git-fixes).
• amd-xgbe: Add additional dynamic debug messages (git-fixes).
• amd-xgbe: Add additional ethtool statistics (git-fixes).
• amd-xgbe: Add ethtool show/set channels support (git-fixes).
• amd-xgbe: Add ethtool show/set ring parameter support (git-fixes).
• amd-xgbe: Add ethtool support to retrieve SFP module info (git-fixes).
• amd-xgbe: Add hardware features debug output (git-fixes).
• amd-xgbe: Add NUMA affinity support for IRQ hints (git-fixes).
• amd-xgbe: Add NUMA affinity support for memory allocations (git-fixes).
• amd-xgbe: Add per queue Tx and Rx statistics (git-fixes).
• amd-xgbe: Advertise FEC support with the KR re-driver (git-fixes).
• amd-xgbe: Always attempt link training in KR mode (git-fixes).
• amd-xgbe: Be sure driver shuts down cleanly on module removal (git-fixes).
• amd-xgbe: Convert to generic power management (git-fixes).
• amd-xgbe: Fix debug output of max channel counts (git-fixes).
• amd-xgbe: Fix error path in xgbe_mod_init() (git-fixes).
• amd-xgbe: Fixes for working with PHYs that support 2.5GbE (git-fixes).…

The SUSE Linux Enterprise 15 SP2 kernel Azure was updated to receive various security and bugfixes.

The following security bugs were fixed:

• CVE-2020-25656: Fixed a concurrency use-after-free in vt_do_kdgkb_ioctl (bnc#1177766).
• CVE-2020-25285: Fixed a race condition between hugetlb sysctl handlers in mm/hugetlb.c (bnc#1176485).
• CVE-2020-14351: Fixed a race in the perf_mmap_close() function (bsc#1177086).
• CVE-2020-16120: Fixed a permissions issue in ovl_path_open() (bsc#1177470).
• CVE-2020-12351: Implemented a kABI workaround for bluetooth l2cap_ops filter addition (bsc#1177724).
• CVE-2020-12352: Fixed an information leak when processing certain AMP packets aka 'BleedingTooth' (bsc#1177725).
• CVE-2020-25212: Fixed a TOCTOU mismatch in the NFS client code (bnc#1176381).
• CVE-2020-25645: Fixed an an issue in IPsec that caused traffic between two Geneve endpoints to be unencrypted (bnc#1177511).
• CVE-2020-24490: Fixed a heap buffer overflow when processing extended advertising report events aka 'BleedingTooth' aka 'BadVibes' (bsc#1177726).
• CVE-2020-25641: Fixed a zero-length biovec request issued by the block subsystem could have caused the kernel to enter an infinite loop, causing a denial of service (bsc#1177121).
• CVE-2020-25643: Fixed a memory corruption and a read overflow which could have caused by improper input validation in the ppp_cp_parse_cr function (bsc#1177206).
• CVE-2020-27673: Fixed an issue where rogue guests could have caused denial of service of Dom0 via high frequency events (XSA-332 bsc#1177411)
• CVE-2020-27675: Fixed a race condition in event handler which may crash dom0 (XSA-331 bsc#1177410).
• CVE-2020-25705: A ICMP global rate limiting side-channel was removed which could lead to e.g. the SADDNS attack (bsc#1175721)

The following non-security bugs were fixed:

• 9p: Fix memory leak in v9fs_mount (git-fixes).
• ACPI: Always build evged in (git-fixes).
• ACPI: button: fix handling lid state changes when input device closed (git-fixes).
• ACPI: configfs: Add missing config_item_put() to fix refcount leak (git-fixes).
• acpi-cpufreq: Honor _PSD table setting on new AMD CPUs (git-fixes).
• ACPI: debug: do not allow debugging when ACPI is disabled (git-fixes).
• ACPI: EC: Reference count query handlers under lock (git-fixes).
• act_ife: load meta modules before tcf_idr_check_alloc() (networking-stable-20_09_24).
• Add CONFIG_CHECK_CODESIGN_EKU
• airo: Fix read overflows sending packets (git-fixes).
• ALSA: ac97: (cosmetic) align argument names (git-fixes).
• ALSA: aoa: i2sbus: use DECLARE_COMPLETION_ONSTACK() macro (git-fixes).
• ALSA: asihpi: fix spellint typo in comments (git-fixes).
• ALSA: atmel: ac97: clarify operator precedence (git-fixes).
• ALSA: bebob: potential info leak in hwdep_read() (git-fixes).
• ALSA: compress_offload: remove redundant initialization (git-fixes).
• ALSA: core: init: use DECLARE_COMPLETION_ONSTACK() macro (git-fixes).
• ALSA: core: pcm: simplify locking for timers (git-fixes).
• ALSA: core: timer: clarify operator precedence (git-fixes).
• ALSA: core: timer: remove redundant assignment (git-fixes).
• ALSA: ctl: Workaround for lockdep warning wrt card->ctl_files_rwlock (git-fixes).
• ALSA: fireworks: use semicolons rather than commas to separate statements (git-fixes).
• ALSA: hda: auto_parser: remove shadowed variable declaration (git-fixes).
• ALSA: hda: (cosmetic) align function parameters (git-fixes).
• ALSA: hda - Do not register a cb func if it is registered already (git-fixes).
• ALSA: hda - Fix the return value if cb func is already registered (git-fixes).
• ALSA: hda/hdmi: fix incorrect locking in hdmi_pcm_close (git-fixes).
• ALSA: hda/realtek - Add mute Led support for HP Elitebook 845 G7 (git-fixes).
• ALSA: hda/realtek: Enable audio jacks of ASUS D700SA with ALC887 (git-fixes).
• ALSA: hda/realtek - set mic to auto detect on a HP AIO machine (git-fixes).
• ALSA: hda/realtek - The front Mic on a HP machine does not work (git-fixes).
• ALSA: hda: use…

The SUSE Linux Enterprise 15 LTSS kernel was updated to receive various security and bug fixes.

The following security bugs were fixed:

• CVE-2020-25705: A flaw in the way reply ICMP packets are limited in was found that allowed to quickly scan open UDP ports. This flaw allowed an off-path remote user to effectively bypassing source port UDP randomization. The highest threat from this vulnerability is to confidentiality and possibly integrity, because software and services that rely on UDP source port randomization (like DNS) are indirectly affected as well. Kernel versions may be vulnerable to this issue (bsc#1175721, bsc#1178782).
• CVE-2020-25704: Fixed a memory leak in perf_event_parse_addr_filter() (bsc#1178393).
• CVE-2020-25668: Fixed a use-after-free in con_font_op() (bnc#1178123).
• CVE-2020-25656: Fixed a concurrency use-after-free in vt_do_kdgkb_ioctl (bnc#1177766).
• CVE-2020-25285: Fixed a race condition between hugetlb sysctl handlers in mm/hugetlb.c (bnc#1176485).
• CVE-2020-0430: Fixed an OOB read in skb_headlen of /include/linux/skbuff.h (bnc#1176723).
• CVE-2020-14351: Fixed a race in the perf_mmap_close() function (bsc#1177086).
• CVE-2020-16120: Fixed permission check to open real file when using overlayfs. It was possible to have a file not readable by an unprivileged user be copied to a mountpoint controlled by that user and then be able to access the file (bsc#1177470).
• CVE-2020-8694: Restricted energy meter to root access (bsc#1170415).
• CVE-2020-12351: Fixed a type confusion while processing AMP packets aka 'BleedingTooth' aka 'BadKarma' (bsc#1177724).
• CVE-2020-12352: Fixed an information leak when processing certain AMP packets aka 'BleedingTooth' (bsc#1177725).
• CVE-2020-25212: Fixed getxattr kernel panic and memory overflow (bsc#1176381).
• CVE-2020-25645: Fixed an an issue in IPsec that caused traffic between two Geneve endpoints to be unencrypted (bnc#1177511).
• CVE-2020-2521: Fixed getxattr kernel panic and memory overflow (bsc#1176381).
• CVE-2020-14381: Fixed a use-after-free in the fast user mutex (futex) wait operation, which could have lead to memory corruption and possibly privilege escalation (bsc#1176011).
• CVE-2020-25643: Fixed a memory corruption and a read overflow which could have caused by improper input validation in the ppp_cp_parse_cr function (bsc#1177206).
• CVE-2020-25641: Fixed a zero-length biovec request issued by the block subsystem could have caused the kernel to enter an infinite loop, causing a denial of service (bsc#1177121).
• CVE-2020-26088: Fixed an improper CAP_NET_RAW check in NFC socket creation could have been used by local attackers to create raw sockets, bypassing security mechanisms (bsc#1176990).
• CVE-2020-14390: Fixed an out-of-bounds memory write leading to memory corruption or a denial of service when changing screen size (bnc#1176235).
• CVE-2020-0432: Fixed an out of bounds write due to an integer overflow (bsc#1176721).
• CVE-2020-0427: Fixed an out of bounds read due to a use after free (bsc#1176725).
• CVE-2020-0431: Fixed an out of bounds write due to a missing bounds check (bsc#1176722).
• CVE-2020-0404: Fixed a linked list corruption due to an unusual root cause (bsc#1176423).
• CVE-2020-25284: Fixed an incomplete permission checking for access to rbd devices, which could have been leveraged by local attackers to map or unmap rbd block devices (bsc#1176482).
• CVE-2020-27673: Fixed an issue where rogue guests could have caused denial of service of Dom0 via high frequency events (XSA-332 bsc#1177411)
• CVE-2020-27675: Fixed a race condition in event handler which may crash dom0 (XSA-331 bsc#1177410).

The following non-security bugs were fixed:

• btrfs: cleanup root usage by btrfs_get_alloc_profile (bsc#1131277).
• btrfs: reloc: clear DEAD_RELOC_TREE bit for orphan roots to prevent runaway balance (bsc#1171417 bsc#1160947 bsc#1172366 bsc#1176922).
• btrfs: reloc: fix reloc root leak and NULL pointer dereference (bsc#1171417…

The SUSE Linux Enterprise 12 SP4 kernel was updated to receive various security and bug fixes.

The following security bugs were fixed:

• CVE-2020-25705: A flaw in the way reply ICMP packets are limited in was found that allowed to quickly scan open UDP ports. This flaw allowed an off-path remote user to effectively bypassing source port UDP randomization. The highest threat from this vulnerability is to confidentiality and possibly integrity, because software and services that rely on UDP source port randomization (like DNS) are indirectly affected as well. Kernel versions may be vulnerable to this issue (bsc#1175721, bsc#1178782).
• CVE-2020-25704: Fixed a memory leak in perf_event_parse_addr_filter() (bsc#1178393).
• CVE-2020-25668: Fixed a use-after-free in con_font_op() (bnc#1178123).
• CVE-2020-25656: Fixed a concurrency use-after-free in vt_do_kdgkb_ioctl (bnc#1177766).
• CVE-2020-25285: Fixed a race condition between hugetlb sysctl handlers in mm/hugetlb.c (bnc#1176485).
• CVE-2020-0430: Fixed an OOB read in skb_headlen of /include/linux/skbuff.h (bnc#1176723).
• CVE-2020-14351: Fixed a race in the perf_mmap_close() function (bsc#1177086).
• CVE-2020-16120: Fixed a permissions issue in ovl_path_open() (bsc#1177470).
• CVE-2020-8694: Restricted energy meter to root access (bsc#1170415).
• CVE-2020-12351: Implemented a kABI workaround for bluetooth l2cap_ops filter addition (bsc#1177724).
• CVE-2020-12352: Fixed an information leak when processing certain AMP packets aka 'BleedingTooth' (bsc#1177725).
• CVE-2020-25212: Fixed a TOCTOU mismatch in the NFS client code (bnc#1176381).
• CVE-2020-25645: Fixed an an issue in IPsec that caused traffic between two Geneve endpoints to be unencrypted (bnc#1177511).
• CVE-2020-14381: Fixed a UAF in the fast user mutex (futex) wait operation (bsc#1176011).
• CVE-2020-25643: Fixed an improper input validation in the ppp_cp_parse_cr function of the HDLC_PPP module (bnc#1177206).
• CVE-2020-25641: Fixed a zero-length biovec request issued by the block subsystem could have caused the kernel to enter an infinite loop, causing a denial of service (bsc#1177121).
• CVE-2020-26088: Fixed an improper CAP_NET_RAW check in NFC socket creation could have been used by local attackers to create raw sockets, bypassing security mechanisms (bsc#1176990).
• CVE-2020-14390: Fixed an out-of-bounds memory write leading to memory corruption or a denial of service when changing screen size (bnc#1176235).
• CVE-2020-0432: Fixed an out of bounds write due to an integer overflow (bsc#1176721).
• CVE-2020-0427: Fixed an out of bounds read due to a use after free (bsc#1176725).
• CVE-2020-0431: Fixed an out of bounds write due to a missing bounds check (bsc#1176722).
• CVE-2020-0404: Fixed a linked list corruption due to an unusual root cause (bsc#1176423).
• CVE-2020-25284: Fixed an incomplete permission checking for access to rbd devices, which could have been leveraged by local attackers to map or unmap rbd block devices (bsc#1176482).
• CVE-2020-27673: Fixed an issue where rogue guests could have caused denial of service of Dom0 via high frequency events (XSA-332 bsc#1177411)
• CVE-2020-27675: Fixed a race condition in event handler which may crash dom0 (XSA-331 bsc#1177410).

The following non-security bugs were fixed:

• btrfs: remove root usage from can_overcommit (bsc#1131277).
• hv: vmbus: Add timeout to vmbus_wait_for_unload (bsc#1177816).
• hyperv_fb: disable superfluous VERSION_WIN10_V5 case (bsc#1175306).
• hyperv_fb: Update screen_info after removing old framebuffer (bsc#1175306).
• livepatch: Add -fdump-ipa-clones to build (). Add support for -fdump-ipa-clones GCC option. Update config files accordingly.
• livepatch: Test if -fdump-ipa-clones is really available As of now we add -fdump-ipa-clones unconditionally. It does not cause a trouble if the kernel is build with the supported toolchain. Otherwise it could fail easily. Do the correct thing and test for the availability.
• NFS: On fatal…

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)

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)

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)

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)

It was discovered that debugfs in the Linux kernel as used by blktrace contained a use-after-free in some situations. A privileged local attacker could possibly use this to cause a denial of service (system crash). (CVE-2019-19770)

It was discovered that a race condition existed in the binder IPC implementation in the Linux kernel, 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-2020-0423)

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)

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)

Keyu Man discovered that the ICMP global rate limiter in the Linux kernel could be used to assist in scanning open UDP ports. A remote attacker could use to facilitate attacks on UDP based services that depend on source port randomization. (CVE-2020-25705)

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)

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)

Ryan Hall discovered that the Intel 700 Series Ethernet Controllers driver in the Linux kernel did not properly deallocate memory in some conditions. A local attacker could use this to cause a denial of service (kernel memory exhaustion). (CVE-2019-0148)

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)

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)

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)

It was discovered that Power 9 processors could be coerced to expose information from the L1 cache in certain situations. A local attacker could use this to expose sensitive information. (CVE-2020-4788)

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…