CVE-2021-4454

In the Linux kernel, the following vulnerability has been resolved: can: j1939: fix errant WARN_ON_ONCE in j1939_session_deactivate The conclusion "j1939_session_deactivate() should be called with a session ref-count of at least 2" is incorrect. In some concurrent scenarios, j1939_session_deactivate can be called with the session ref-count less than 2. But there is not any problem because it will check the session active state before session putting in j1939_session_deactivate_locked(). Here is the concurrent scenario of the problem reported by syzbot and my reproduction log. cpu0 cpu1 j1939_xtp_rx_eoma j1939_xtp_rx_abort_one j1939_session_get_by_addr [kref == 2] j1939_session_get_by_addr [kref == 3] j1939_session_deactivate [kref == 2] j1939_session_put [kref == 1] j1939_session_completed j1939_session_deactivate WARN_ON_ONCE(kref < 2) ===================================================== WARNING: CPU: 1 PID: 21 at net/can/j1939/transport.c:1088 j1939_session_deactivate+0x5f/0x70 CPU: 1 PID: 21 Comm: ksoftirqd/1 Not tainted 5.14.0-rc7+ #32 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1 04/01/2014 RIP: 0010:j1939_session_deactivate+0x5f/0x70 Call Trace: j1939_session_deactivate_activate_next+0x11/0x28 j1939_xtp_rx_eoma+0x12a/0x180 j1939_tp_recv+0x4a2/0x510 j1939_can_recv+0x226/0x380 can_rcv_filter+0xf8/0x220 can_receive+0x102/0x220 ? process_backlog+0xf0/0x2c0 can_rcv+0x53/0xf0 __netif_receive_skb_one_core+0x67/0x90 ? process_backlog+0x97/0x2c0 __netif_receive_skb+0x22/0x80

• gpiolib: cdev: Set lineevent_state::irq after IRQ register successfully {CVE-2022-48660}
• ipv4: check for NULL idev in ip_route_use_hint() {CVE-2024-36008}
• KEYS: trusted: Do not use WARN when encode fails {CVE-2024-36975}
• Fix userfaultfd_api to return EINVAL as expected {CVE-2024-41027}
• xhci: Fix null pointer dereference when host dies {CVE-2023-52898}
• sctp: sysctl: auth_enable: avoid using current->nsproxy {CVE-2025-21638}
• blk-mq: fix IO hang from sbitmap wakeup race {CVE-2024-26671}
• net: openvswitch: fix flow memory leak in ovs_flow_cmd_new {CVE-2023-52977}
• gpiolib: fix memory leak in gpiochip_setup_dev() {CVE-2022-48975}
• HID: betop: check shape of output reports {CVE-2023-53015}
• mm/swapfile: add cond_resched() in get_swap_pages() {CVE-2023-52932}
• HV: hv_balloon: fix memory leak with using debugfs_lookup() {CVE-2023-52937}
• drm/i915: Fix a memory leak with reused mmap_offset {CVE-2023-53002}
• ptdma: pt_core_execute_cmd() should use spinlock {CVE-2023-53013}
• RDMA/core: Fix ib block iterator counter overflow {CVE-2023-53026}
• Bluetooth: hci_conn: Fix memory leaks {CVE-2023-53018}
• scsi: target: pscsi: Fix bio_put() for error case {CVE-2024-26760}
• sctp: Prevent TOCTOU out-of-bounds write {CVE-2025-40331}
• pnfs/flexfiles: Fix memory leak in nfs4_ff_alloc_deviceid_node() {CVE-2026-23038}
• cpufreq: intel_pstate: Fix object lifecycle issue in update_qos_request() {CVE-2025-40194}
• ALSA: hda/cs8409: Fix possible NULL dereference {CVE-2024-50160}
• nbd: don't allow reconnect after disconnect {CVE-2025-21731}
• openvswitch: fix lockup on tx to unregistering netdev with carrier {CVE-2025-21681}
• ext4: detect invalid INLINE_DATA + EXTENTS flag combination {CVE-2025-40167}
• ext4: xattr: fix null pointer deref in ext4_raw_inode() {CVE-2025-68820}
• net: fix memory leak in skb_segment_list for GRO packets {CVE-2026-22979}
• wifi: brcmfmac: fix crash while sending Action Frames in standalone AP Mode {CVE-2025-40321}
• ipvs: fix ipv4 null-ptr-deref in route error path {CVE-2025-68813}
• ASoC: Intel: bytcr_rt5651: Fix invalid quirk input mapping {CVE-2025-40121}
• i40e: Fix macvlan leak by synchronizing access to mac_filter_hash {CVE-2024-50041}
• net/mlx5e: Fix NULL deref in mlx5e_tir_builder_alloc() {CVE-2024-50000}
• bpf: Fix reference count leak in bpf_prog_test_run_xdp() {CVE-2026-22994}
• xsk: check IFF_UP earlier in Tx path {CVE-2023-53240}
• firmware: cs_dsp: Prevent buffer overrun when processing V2 alg headers {CVE-2024-41038}
• virtgpu: don't reset on shutdown {CVE-2025-38064}
• xen/netfront: fix crash when removing device {CVE-2022-48969}
• mptcp: do not fallback when OoO is present {CVE-2024-50185}
• can: j1939: add missing calls in NETDEV_UNREGISTER notification handler {CVE-2025-39925}
• netfilter: nf_tables: remove redundant chain validation on register store {CVE-2025-71160}
• xfs: fix use-after-free in xattr node block inactivation {CVE-2026-43053}
• ext4: fix racy may inline data check in dio write {CVE-2023-52786}
• drm/amdgpu/fence: Fix oops due to non-matching drm_sched init/fini {CVE-2023-52738}
• macsec: fix UAF bug for real_dev {CVE-2022-49390}
• drm/i915/gem: Fix Virtual Memory mapping boundaries calculation {CVE-2024-42259}
• mm/shmem: disable PMD-sized page cache if needed {CVE-2024-42241}
• driver: iio: add missing checks on iio_info's callback access {CVE-2024-46715}
• udmabuf: fix memory leak on last export_udmabuf() error path {CVE-2024-56712}
• ALSA: control: Avoid WARN() for symlink errors {CVE-2024-56657}
• mm/mempolicy: fix migrate_to_node() assuming there is at least one VMA in a MM {CVE-2024-56611}
• eth: bnxt: always recalculate features after XDP clearing, fix null-deref {CVE-2025-21682}
• net: annotate data-races around sk->sk_{data_ready,write_space} {CVE-2026-23302}
• udmabuf: change folios array from kmalloc to kvmalloc {CVE-2024-56544}
• RDMA/mlx5: Move events notifier registration to be after device registration {CVE-2024-53224}
• dlm: fix possible lkb_resource…

The SUSE Linux Enterprise 15 SP5 RT kernel was updated to receive various security bugfixes.

The following security bugs were fixed:

• CVE-2022-49053: scsi: target: tcmu: Fix possible page UAF (bsc#1237918).
• CVE-2022-49465: blk-throttle: Set BIO_THROTTLED when bio has been throttled (bsc#1238919).
• CVE-2022-49739: gfs2: Always check inode size of inline inodes (bsc#1240207).
• CVE-2023-52935: mm/khugepaged: fix ->anon_vma race (bsc#1240276).
• CVE-2024-53124: net: fix data-races around sk->sk_forward_alloc (bsc#1234074).
• CVE-2024-53176: smb: During unmount, ensure all cached dir instances drop their dentry (bsc#1234894).
• CVE-2024-53178: smb: Do not leak cfid when reconnect races with open_cached_dir (bsc#1234895).
• CVE-2024-56651: can: hi311x: hi3110_can_ist(): fix potential use-after-free (bsc#1235528).
• CVE-2024-57996: net_sched: sch_sfq: do not allow 1 packet limit (bsc#1239076).
• CVE-2024-58013: Bluetooth: MGMT: Fix slab-use-after-free Read in mgmt_remove_adv_monitor_sync (bsc#1239095).
• CVE-2024-58014: wifi: brcmsmac: add gain range check to wlc_phy_iqcal_gainparams_nphy() (bsc#1239109).
• CVE-2025-21693: mm: zswap: properly synchronize freeing resources during CPU hotunplug (bsc#1237029).
• CVE-2025-21718: net: rose: fix timer races against user threads (bsc#1239073).
• CVE-2025-21772: partitions: mac: fix handling of bogus partition table (bsc#1238911).
• CVE-2025-21780: drm/amdgpu: avoid buffer overflow attach in smu_sys_set_pp_table() (bsc#1239115).

The following non-security bugs were fixed:

• ACPI: processor: idle: Return an error if both P_LVL{2,3} idle states are invalid (bsc#1237530).
• RDMA/mana_ib: Prefer struct_size over open coded arithmetic (bsc#1239016).
• RDMA/mana_ib: Use v2 version of cfg_rx_steer_req to enable RX coalescing (bsc#1239016).
• Revert 'gfs2: Fix inode height consistency check (git-fixes).
• btrfs: defrag: do not use merged extent map for their generation check (bsc#1239968).
• btrfs: fix defrag not merging contiguous extents due to merged extent maps (bsc#1239968).
• btrfs: fix extent map merging not happening for adjacent extents (bsc#1239968).
• btrfs: send: allow cloning non-aligned extent if it ends at i_size (bsc#1239969).
• btrfs: send: fix invalid clone operation for file that got its size decreased (bsc#1239969).
• cifs: Add a laundromat thread for cached directories (git-fixes).
• cifs: fix potential null pointer use in destroy_workqueue in init_cifs error path (git-fixes).
• gfs2: Fix inode height consistency check (git-fixes).
• mm/mmu_notifier.c: fix race in mmu_interval_notifier_remove() (bsc#1239126).
• mm: zswap: move allocations during CPU init outside the lock (git-fixes).
• net: mana: Add flex array to struct mana_cfg_rx_steer_req_v2 (bsc#1239016).
• net: mana: Allow variable size indirection table (bsc#1239016).
• net: mana: Avoid open coded arithmetic (bsc#1239016).
• net: mana: Support holes in device list reply msg (bsc#1240133).
• sched/membarrier: Fix redundant load of membarrier_state (bsc#1232743).
• smb3: allow controlling length of time directory entries are cached with dir leases (git-fixes).
• smb3: do not start laundromat thread when dir leases disabled (git-fixes).
• smb3: retrying on failed server close (git-fixes).
• smb: client: destroy cfid_put_wq on module exit (git-fixes).
• smb: client: disable directory caching when dir_cache_timeout is zero (git-fixes).
• smb: client: do not start laundromat thread on nohandlecache (git-fixes).
• smb: client: make laundromat a delayed worker (git-fixes).
• smb: client: properly close cfids on umount (bsc#1231432, bsc#1232299, bsc#1235599, bsc#1234896).
• tpm: send_data: Wait longer for the TPM to become ready (bsc#1235870).

The SUSE Linux Enterprise 15 SP4 RT kernel was updated to receive various security bugfixes.

The following security bugs were fixed:

• CVE-2022-49053: scsi: target: tcmu: Fix possible page UAF (bsc#1237918).
• CVE-2022-49465: blk-throttle: Set BIO_THROTTLED when bio has been throttled (bsc#1238919).
• CVE-2022-49739: gfs2: Always check inode size of inline inodes (bsc#1240207).
• CVE-2023-52935: mm/khugepaged: fix ->anon_vma race (bsc#1240276).
• CVE-2024-2201: Fixed information leak in x86/BHI (bsc#1217339).
• CVE-2024-41092: drm/i915/gt: Fix potential UAF by revoke of fence registers (bsc#1228483).
• CVE-2024-42098: crypto: ecdh - explicitly zeroize private_key (bsc#1228779).
• CVE-2024-42229: crypto: aead,cipher - zeroize key buffer after use (bsc#1228708).
• CVE-2024-53064: idpf: fix idpf_vc_core_init error path (bsc#1233558 bsc#1234464).
• CVE-2024-56651: can: hi311x: hi3110_can_ist(): fix potential use-after-free (bsc#1235528).
• CVE-2024-57996: net_sched: sch_sfq: do not allow 1 packet limit (bsc#1239076).
• CVE-2024-58014: wifi: brcmsmac: add gain range check to wlc_phy_iqcal_gainparams_nphy() (bsc#1239109).
• CVE-2024-58083: KVM: Explicitly verify target vCPU is online in kvm_get_vcpu() (bsc#1239036).
• CVE-2025-21693: mm: zswap: properly synchronize freeing resources during CPU hotunplug (bsc#1237029).
• CVE-2025-21714: RDMA/mlx5: Fix implicit ODP use after free (bsc#1237890).
• CVE-2025-21718: net: rose: fix timer races against user threads (bsc#1239073).
• CVE-2025-21732: RDMA/mlx5: Fix a race for an ODP MR which leads to CQE with error (bsc#1237877).
• CVE-2025-21753: btrfs: fix use-after-free when attempting to join an aborted transaction (bsc#1237875).
• CVE-2025-21772: partitions: mac: fix handling of bogus partition table (bsc#1238911).
• CVE-2025-21780: drm/amdgpu: avoid buffer overflow attach in smu_sys_set_pp_table() (bsc#1239115).
• CVE-2025-21839: kABI: Fix kABI after backport od CVE-2025-21839 (bsc#1239061).

The following non-security bugs were fixed:

• ACPI: processor: idle: Return an error if both P_LVL{2,3} idle states are invalid (bsc#1237530).
• RDMA/mana_ib: Prefer struct_size over open coded arithmetic (bsc#1239016).
• RDMA/mana_ib: Use v2 version of cfg_rx_steer_req to enable RX coalescing (bsc#1239016).
• RDMA/mlx5: Fix implicit ODP hang on parent deregistration (git-fixes)
• btrfs: defrag: do not use merged extent map for their generation check (bsc#1239968).
• btrfs: fix defrag not merging contiguous extents due to merged extent maps (bsc#1239968).
• btrfs: fix extent map merging not happening for adjacent extents (bsc#1239968).
• btrfs: send: allow cloning non-aligned extent if it ends at i_size (bsc#1239969).
• btrfs: send: fix invalid clone operation for file that got its size decreased (bsc#1239969).
• gfs2: Fix inode height consistency check (git-fixes).
• mm/mmu_notifier.c: fix race in mmu_interval_notifier_remove() (bsc#1239126).
• mm: zswap: move allocations during CPU init outside the lock (git-fixes).
• net: mana: Add flex array to struct mana_cfg_rx_steer_req_v2 (bsc#1239016).
• net: mana: Allow variable size indirection table (bsc#1239016).
• net: mana: Avoid open coded arithmetic (bsc#1239016).
• net: mana: Fix error handling in mana_create_txq/rxq's NAPI cleanup (bsc#1240195).
• net: mana: Support holes in device list reply msg (bsc#1240133).
• x86/bhi: Avoid warning in #DB handler due to BHI mitigation (git-fixes).
• x86/bugs: Cache the value of MSR_IA32_ARCH_CAPABILITIES (git-fixes).
• x86/bugs: Fix BHI documentation (git-fixes).
• x86/bugs: Fix BHI handling of RRSBA (git-fixes).
• x86/bugs: Fix BHI retpoline check (git-fixes).
• x86/bugs: Fix return type of spectre_bhi_state() (git-fixes).
• x86/bugs: Remove CONFIG_BHI_MITIGATION_AUTO and spectre_bhi=auto (git-fixes).

The SUSE Linux Enterprise 15 SP4 kernel was updated to receive various security bugfixes.

The following security bugs were fixed:

• CVE-2022-49053: scsi: target: tcmu: Fix possible page UAF (bsc#1237918).
• CVE-2022-49465: blk-throttle: Set BIO_THROTTLED when bio has been throttled (bsc#1238919).
• CVE-2022-49739: gfs2: Always check inode size of inline inodes (bsc#1240207).
• CVE-2023-52935: mm/khugepaged: fix ->anon_vma race (bsc#1240276).
• CVE-2024-53064: idpf: fix idpf_vc_core_init error path (bsc#1233558 bsc#1234464).
• CVE-2024-56651: can: hi311x: hi3110_can_ist(): fix potential use-after-free (bsc#1235528).
• CVE-2024-58083: KVM: Explicitly verify target vCPU is online in kvm_get_vcpu() (bsc#1239036).
• CVE-2025-21693: mm: zswap: properly synchronize freeing resources during CPU hotunplug (bsc#1237029).
• CVE-2025-21714: RDMA/mlx5: Fix implicit ODP use after free (bsc#1237890).
• CVE-2025-21732: RDMA/mlx5: Fix a race for an ODP MR which leads to CQE with error (bsc#1237877).
• CVE-2025-21753: btrfs: fix use-after-free when attempting to join an aborted transaction (bsc#1237875).
• CVE-2025-21772: partitions: mac: fix handling of bogus partition table (bsc#1238911).

The following non-security bugs were fixed:

• ACPI: processor: idle: Return an error if both P_LVL{2,3} idle states are invalid (bsc#1237530).
• RDMA/mana_ib: Prefer struct_size over open coded arithmetic (bsc#1239016).
• RDMA/mana_ib: Use v2 version of cfg_rx_steer_req to enable RX coalescing (bsc#1239016).
• RDMA/mlx5: Fix implicit ODP hang on parent deregistration (git-fixes)
• btrfs: defrag: do not use merged extent map for their generation check (bsc#1239968).
• btrfs: fix defrag not merging contiguous extents due to merged extent maps (bsc#1239968).
• btrfs: fix extent map merging not happening for adjacent extents (bsc#1239968).
• btrfs: send: allow cloning non-aligned extent if it ends at i_size (bsc#1239969).
• btrfs: send: fix invalid clone operation for file that got its size decreased (bsc#1239969).
• gfs2: Fix inode height consistency check (git-fixes).
• mm/mmu_notifier.c: fix race in mmu_interval_notifier_remove() (bsc#1239126).
• mm: zswap: move allocations during CPU init outside the lock (git-fixes).
• net: mana: Add flex array to struct mana_cfg_rx_steer_req_v2 (bsc#1239016).
• net: mana: Allow variable size indirection table (bsc#1239016).
• net: mana: Avoid open coded arithmetic (bsc#1239016).
• net: mana: Fix error handling in mana_create_txq/rxq's NAPI cleanup (bsc#1240195).
• net: mana: Support holes in device list reply msg (bsc#1240133).

The SUSE Linux Enterprise 15 SP5 kernel was updated to receive various security bugfixes.

The following security bugs were fixed:

• CVE-2022-49053: scsi: target: tcmu: Fix possible page UAF (bsc#1237918).
• CVE-2022-49465: blk-throttle: Set BIO_THROTTLED when bio has been throttled (bsc#1238919).
• CVE-2022-49739: gfs2: Always check inode size of inline inodes (bsc#1240207).
• CVE-2023-52935: mm/khugepaged: fix ->anon_vma race (bsc#1240276).
• CVE-2024-53124: net: fix data-races around sk->sk_forward_alloc (bsc#1234074).
• CVE-2024-53176: smb: During unmount, ensure all cached dir instances drop their dentry (bsc#1234894).
• CVE-2024-53178: smb: Do not leak cfid when reconnect races with open_cached_dir (bsc#1234895).
• CVE-2024-56651: can: hi311x: hi3110_can_ist(): fix potential use-after-free (bsc#1235528).
• CVE-2024-57996: net_sched: sch_sfq: do not allow 1 packet limit (bsc#1239076).
• CVE-2024-58013: Bluetooth: MGMT: Fix slab-use-after-free Read in mgmt_remove_adv_monitor_sync (bsc#1239095).
• CVE-2024-58014: wifi: brcmsmac: add gain range check to wlc_phy_iqcal_gainparams_nphy() (bsc#1239109).
• CVE-2025-21693: mm: zswap: properly synchronize freeing resources during CPU hotunplug (bsc#1237029).
• CVE-2025-21718: net: rose: fix timer races against user threads (bsc#1239073).
• CVE-2025-21772: partitions: mac: fix handling of bogus partition table (bsc#1238911).
• CVE-2025-21780: drm/amdgpu: avoid buffer overflow attach in smu_sys_set_pp_table() (bsc#1239115).

The following non-security bugs were fixed:

• ACPI: processor: idle: Return an error if both P_LVL{2,3} idle states are invalid (bsc#1237530).
• btrfs: defrag: do not use merged extent map for their generation check (bsc#1239968).
• btrfs: fix defrag not merging contiguous extents due to merged extent maps (bsc#1239968).
• btrfs: fix extent map merging not happening for adjacent extents (bsc#1239968).
• btrfs: send: allow cloning non-aligned extent if it ends at i_size (bsc#1239969).
• btrfs: send: fix invalid clone operation for file that got its size decreased (bsc#1239969).
• cifs: Add a laundromat thread for cached directories (git-fixes).
• cifs: fix potential null pointer use in destroy_workqueue in init_cifs error path (git-fixes).
• gfs2: Fix inode height consistency check (git-fixes).
• mm: zswap: move allocations during CPU init outside the lock (git-fixes).
• mm/mmu_notifier.c: fix race in mmu_interval_notifier_remove() (bsc#1239126).
• net: mana: Add flex array to struct mana_cfg_rx_steer_req_v2 (bsc#1239016).
• net: mana: Allow variable size indirection table (bsc#1239016).
• net: mana: Avoid open coded arithmetic (bsc#1239016).
• net: mana: Support holes in device list reply msg (bsc#1240133).
• RDMA/mana_ib: Prefer struct_size over open coded arithmetic (bsc#1239016).
• RDMA/mana_ib: Use v2 version of cfg_rx_steer_req to enable RX coalescing (bsc#1239016).
• sched/membarrier: Fix redundant load of membarrier_state (bsc#1232743).
• smb: client: destroy cfid_put_wq on module exit (git-fixes).
• smb: client: disable directory caching when dir_cache_timeout is zero (git-fixes).
• smb: client: do not start laundromat thread on nohandlecache (git-fixes).
• smb: client: make laundromat a delayed worker (git-fixes).
• smb: client: properly close cfids on umount (bsc#1231432, bsc#1232299, bsc#1235599, bsc#1234896).
• smb3: allow controlling length of time directory entries are cached with dir leases (git-fixes).
• smb3: do not start laundromat thread when dir leases disabled (git-fixes).
• smb3: retrying on failed server close (git-fixes).
• tpm: send_data: Wait longer for the TPM to become ready (bsc#1235870).