In the Linux kernel, the following vulnerability has been resolved: rcutorture: Fix ksoftirqd boosting timing and iteration The RCU priority boosting can fail in two situations: 1) If (nr_cpus= > maxcpus=), which means if the total number of CPUs is higher than those brought online at boot, then torture_onoff() may later bring up CPUs that weren't online on boot. Now since rcutorture initialization only boosts the ksoftirqds of the CPUs that have been set online on boot, the CPUs later set online by torture_onoff won't benefit from the boost, making RCU priority boosting fail. 2) The ksoftirqd kthreads are boosted after the creation of rcu_torture_boost() kthreads, which opens a window large enough for these rcu_torture_boost() kthreads to wait (despite running at FIFO priority) for ksoftirqds that are still running at SCHED_NORMAL priority. The issues can trigger for example with: ./kvm.sh --configs TREE01 --kconfig "CONFIG_RCU_BOOST=y" [ 34.968561] rcu-torture: !!! [ 34.968627] ------------[ cut here ]------------ [ 35.014054] WARNING: CPU: 4 PID: 114 at kernel/rcu/rcutorture.c:1979 rcu_torture_stats_print+0x5ad/0x610 [ 35.052043] Modules linked in: [ 35.069138] CPU: 4 PID: 114 Comm: rcu_torture_sta Not tainted 5.18.0-rc1 #1 [ 35.096424] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.14.0-0-g155821a-rebuilt.opensuse.org 04/01/2014 [ 35.154570] RIP: 0010:rcu_torture_stats_print+0x5ad/0x610 [ 35.198527] Code: 63 1b 02 00 74 02 0f 0b 48 83 3d 35 63 1b 02 00 74 02 0f 0b 48 83 3d 21 63 1b 02 00 74 02 0f 0b 48 83 3d 0d 63 1b 02 00 74 02 <0f> 0b 83 eb 01 0f 8e ba fc ff ff 0f 0b e9 b3 fc ff f82 [ 37.251049] RSP: 0000:ffffa92a0050bdf8 EFLAGS: 00010202 [ 37.277320] rcu: De-offloading 8 [ 37.290367] RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000001 [ 37.290387] RDX: 0000000000000000 RSI: 00000000ffffbfff RDI: 00000000ffffffff [ 37.290398] RBP: 000000000000007b R08: 0000000000000000 R09: c0000000ffffbfff [ 37.290407] R10: 000000000000002a R11: ffffa92a0050bc18 R12: ffffa92a0050be20 [ 37.290417] R13: ffffa92a0050be78 R14: 0000000000000000 R15: 000000000001bea0 [ 37.290427] FS: 0000000000000000(0000) GS:ffff96045eb00000(0000) knlGS:0000000000000000 [ 37.290448] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 37.290460] CR2: 0000000000000000 CR3: 000000001dc0c000 CR4: 00000000000006e0 [ 37.290470] Call Trace: [ 37.295049] <TASK> [ 37.295065] ? preempt_count_add+0x63/0x90 [ 37.295095] ? _raw_spin_lock_irqsave+0x12/0x40 [ 37.295125] ? rcu_torture_stats_print+0x610/0x610 [ 37.295143] rcu_torture_stats+0x29/0x70 [ 37.295160] kthread+0xe3/0x110 [ 37.295176] ? kthread_complete_and_exit+0x20/0x20 [ 37.295193] ret_from_fork+0x22/0x30 [ 37.295218] </TASK> Fix this with boosting the ksoftirqds kthreads from the boosting hotplug callback itself and before the boosting kthreads are created.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - In the Linux kernel, the following vulnerability has been resolved: rcutorture: Fix ksoftirqd boosting     timing and iteration The RCU priority boosting can fail in two situations: 1) If (nr_cpus= > maxcpus=),     which means if the total number of CPUs is higher than those brought online at boot, then torture_onoff()     may later bring up CPUs that weren't online on boot. Now since rcutorture initialization only boosts the     ksoftirqds of the CPUs that have been set online on boot, the CPUs later set online by torture_onoff won't     benefit from the boost, making RCU priority boosting fail. 2) The ksoftirqd kthreads are boosted after the     creation of rcu_torture_boost() kthreads, which opens a window large enough for these rcu_torture_boost()     kthreads to wait (despite running at FIFO priority) for ksoftirqds that are still running at SCHED_NORMAL     priority. The issues can trigger for example with: ./kvm.sh --configs TREE01 --kconfig     CONFIG_RCU_BOOST=y [ 34.968561] rcu-torture: !!! [ 34.968627] ------------[ cut here ]------------ [     35.014054] WARNING: CPU: 4 PID: 114 at kernel/rcu/rcutorture.c:1979 rcu_torture_stats_print+0x5ad/0x610 [     35.052043] Modules linked in: [ 35.069138] CPU: 4 PID: 114 Comm: rcu_torture_sta Not tainted 5.18.0-rc1 #1     [ 35.096424] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS     rel-1.14.0-0-g155821a-rebuilt.opensuse.org 04/01/2014 [ 35.154570] RIP:
    0010:rcu_torture_stats_print+0x5ad/0x610 [ 35.198527] Code: 63 1b 02 00 74 02 0f 0b 48 83 3d 35 63 1b 02     00 74 02 0f 0b 48 83 3d 21 63 1b 02 00 74 02 0f 0b 48 83 3d 0d 63 1b 02 00 74 02 <0f> 0b 83 eb 01 0f 8e ba     fc ff ff 0f 0b e9 b3 fc ff f82 [ 37.251049] RSP: 0000:ffffa92a0050bdf8 EFLAGS: 00010202 [ 37.277320] rcu:
    De-offloading 8 [ 37.290367] RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000001 [     37.290387] RDX: 0000000000000000 RSI: 00000000ffffbfff RDI: 00000000ffffffff [ 37.290398] RBP:
    000000000000007b R08: 0000000000000000 R09: c0000000ffffbfff [ 37.290407] R10: 000000000000002a R11:
    ffffa92a0050bc18 R12: ffffa92a0050be20 [ 37.290417] R13: ffffa92a0050be78 R14: 0000000000000000 R15:
    000000000001bea0 [ 37.290427] FS: 0000000000000000(0000) GS:ffff96045eb00000(0000) knlGS:0000000000000000     [ 37.290448] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 37.290460] CR2: 0000000000000000 CR3:
    000000001dc0c000 CR4: 00000000000006e0 [ 37.290470] Call Trace: [ 37.295049] <TASK> [ 37.295065] ?     preempt_count_add+0x63/0x90 [ 37.295095] ? _raw_spin_lock_irqsave+0x12/0x40 [ 37.295125] ?     rcu_torture_stats_print+0x610/0x610 [ 37.295143] rcu_torture_stats+0x29/0x70 [ 37.295160]     kthread+0xe3/0x110 [ 37.295176] ? kthread_complete_and_exit+0x20/0x20 [ 37.295193] ret_from_fork+0x22/0x30     [ 37.295218] </TASK> Fix this with boosting the ksoftirqds kthreads from the boosting hotplug callback     itself and before the boosting kthreads are created. (CVE-2022-50177)

Note that Nessus relies on the presence of the package as reported by the vendor.

The remote Redhat Enterprise Linux 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2022:7683 advisory.

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

    Security Fix(es):

    * off-path attacker may inject data or terminate victim's TCP session (CVE-2020-36516)

    * race condition in VT_RESIZEX ioctl when vc_cons[i].d is already NULL leading to NULL pointer dereference     (CVE-2020-36558)

    * use-after-free vulnerability in function sco_sock_sendmsg() (CVE-2021-3640)

    * memory leak for large arguments in video_usercopy function in drivers/media/v4l2-core/v4l2-ioctl.c     (CVE-2021-30002)

    * smb2_ioctl_query_info NULL Pointer Dereference (CVE-2022-0168)

    * NULL pointer dereference in udf_expand_file_adinicbdue() during writeback (CVE-2022-0617)

    * swiotlb information leak with DMA_FROM_DEVICE (CVE-2022-0854)

    * uninitialized registers on stack in nft_do_chain can cause kernel pointer leakage to UM (CVE-2022-1016)

    * race condition in snd_pcm_hw_free leading to use-after-free (CVE-2022-1048)

    * use-after-free in tc_new_tfilter() in net/sched/cls_api.c (CVE-2022-1055)

    * use-after-free and memory errors in ext4 when mounting and operating on a corrupted image     (CVE-2022-1184)

    * NULL pointer dereference in x86_emulate_insn may lead to DoS (CVE-2022-1852)

    * buffer overflow in nft_set_desc_concat_parse() (CVE-2022-2078)

    * nf_tables cross-table potential use-after-free may lead to local privilege escalation (CVE-2022-2586)

    * openvswitch: integer underflow leads to out-of-bounds write in reserve_sfa_size() (CVE-2022-2639)

    * use-after-free when psi trigger is destroyed while being polled (CVE-2022-2938)

    * net/packet: slab-out-of-bounds access in packet_recvmsg() (CVE-2022-20368)

    * possible to use the debugger to write zero into a location of choice (CVE-2022-21499)

    * Spectre-BHB (CVE-2022-23960)

    * Post-barrier Return Stack Buffer Predictions (CVE-2022-26373)

    * memory leak in drivers/hid/hid-elo.c (CVE-2022-27950)

    * double free in ems_usb_start_xmit in drivers/net/can/usb/ems_usb.c (CVE-2022-28390)

    * use after free in SUNRPC subsystem (CVE-2022-28893)

    * use-after-free due to improper update of reference count in net/sched/cls_u32.c (CVE-2022-29581)

    * DoS in nfqnl_mangle in net/netfilter/nfnetlink_queue.c (CVE-2022-36946)

    * nfs_atomic_open() returns uninitialized data instead of ENOTDIR (CVE-2022-24448)

    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 Red Hat Enterprise Linux 8.7 Release Notes     linked from the References section.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Severity
245781	Linux Distros Unpatched Vulnerability : CVE-2022-50177	Nessus	Misc.	medium
210815	RHEL 9 : kernel (RHSA-2024:9315)	Nessus	Red Hat Local Security Checks	high
167155	RHEL 8 : kernel (RHSA-2022:7683)	Nessus	Red Hat Local Security Checks	high

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