Vulnerabilities (CVE)

In the Linux kernel, the following vulnerability has been resolved: gve: add missing NULL check for gve_alloc_pending_packet() in TX DQO gve_alloc_pending_packet() can return NULL, but gve_tx_add_skb_dqo() did not check for this case before dereferencing the returned pointer. Add a missing NULL check to prevent a potential NULL pointer dereference when allocation fails. This improves robustness in low-memory scenarios.

In the Linux kernel, the following vulnerability has been resolved: nvmet-tcp: don't restore null sk_state_change queue->state_change is set as part of nvmet_tcp_set_queue_sock(), but if the TCP connection isn't established when nvmet_tcp_set_queue_sock() is called then queue->state_change isn't set and sock->sk->sk_state_change isn't replaced. As such we don't need to restore sock->sk->sk_state_change if queue->state_change is NULL. This avoids NULL pointer dereferences such as this: [ 28 ... In the Linux kernel, the following vulnerability has been resolved: nvmet-tcp: don't restore null sk_state_change queue->state_change is set as part of nvmet_tcp_set_queue_sock(), but if the TCP connection isn't established when nvmet_tcp_set_queue_sock() is called then queue->state_change isn't set and sock->sk->sk_state_change isn't replaced. As such we don't need to restore sock->sk->sk_state_change if queue->state_change is NULL. This avoids NULL pointer dereferences such as this: [ 286.462026][ C0] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 286.462814][ C0] #PF: supervisor instruction fetch in kernel mode [ 286.463796][ C0] #PF: error_code(0x0010) - not-present page [ 286.464392][ C0] PGD 8000000140620067 P4D 8000000140620067 PUD 114201067 PMD 0 [ 286.465086][ C0] Oops: Oops: 0010 [#1] SMP KASAN PTI [ 286.465559][ C0] CPU: 0 UID: 0 PID: 1628 Comm: nvme Not tainted 6.15.0-rc2+ #11 PREEMPT(voluntary) [ 286.466393][ C0] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-3.fc41 04/01/2014 [ 286.467147][ C0] RIP: 0010:0x0 [ 286.467420][ C0] Code: Unable to access opcode bytes at 0xffffffffffffffd6. [ 286.467977][ C0] RSP: 0018:ffff8883ae008580 EFLAGS: 00010246 [ 286.468425][ C0] RAX: 0000000000000000 RBX: ffff88813fd34100 RCX: ffffffffa386cc43 [ 286.469019][ C0] RDX: 1ffff11027fa68b6 RSI: 0000000000000008 RDI: ffff88813fd34100 [ 286.469545][ C0] RBP: ffff88813fd34160 R08: 0000000000000000 R09: ffffed1027fa682c [ 286.470072][ C0] R10: ffff88813fd34167 R11: 0000000000000000 R12: ffff88813fd344c3 [ 286.470585][ C0] R13: ffff88813fd34112 R14: ffff88813fd34aec R15: ffff888132cdd268 [ 286.471070][ C0] FS: 00007fe3c04c7d80(0000) GS:ffff88840743f000(0000) knlGS:0000000000000000 [ 286.471644][ C0] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 286.472543][ C0] CR2: ffffffffffffffd6 CR3: 000000012daca000 CR4: 00000000000006f0 [ 286.473500][ C0] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 286.474467][ C0] DR3: 0000000000000000 DR6: 00000000ffff07f0 DR7: 0000000000000400 [ 286.475453][ C0] Call Trace: [ 286.476102][ C0] <IRQ> [ 286.476719][ C0] tcp_fin+0x2bb/0x440 [ 286.477429][ C0] tcp_data_queue+0x190f/0x4e60 [ 286.478174][ C0] ? __build_skb_around+0x234/0x330 [ 286.478940][ C0] ? rcu_is_watching+0x11/0xb0 [ 286.479659][ C0] ? __pfx_tcp_data_queue+0x10/0x10 [ 286.480431][ C0] ? tcp_try_undo_loss+0x640/0x6c0 [ 286.481196][ C0] ? seqcount_lockdep_reader_access.constprop.0+0x82/0x90 [ 286.482046][ C0] ? kvm_clock_get_cycles+0x14/0x30 [ 286.482769][ C0] ? ktime_get+0x66/0x150 [ 286.483433][ C0] ? rcu_is_watching+0x11/0xb0 [ 286.484146][ C0] tcp_rcv_established+0x6e4/0x2050 [ 286.484857][ C0] ? rcu_is_watching+0x11/0xb0 [ 286.485523][ C0] ? ipv4_dst_check+0x160/0x2b0 [ 286.486203][ C0] ? __pfx_tcp_rcv_established+0x10/0x10 [ 286.486917][ C0] ? lock_release+0x217/0x2c0 [ 286.487595][ C0] tcp_v4_do_rcv+0x4d6/0x9b0 [ 286.488279][ C0] tcp_v4_rcv+0x2af8/0x3e30 [ 286.488904][ C0] ? raw_local_deliver+0x51b/0xad0 [ 286.489551][ C0] ? rcu_is_watching+0x11/0xb0 [ 286.490198][ C0] ? __pfx_tcp_v4_rcv+0x10/0x10 [ 286.490813][ C0] ? __pfx_raw_local_deliver+0x10/0x10 [ 286.491487][ C0] ? __pfx_nf_confirm+0x10/0x10 [nf_conntrack] [ 286.492275][ C0] ? rcu_is_watching+0x11/0xb0 [ 286.492900][ C0] ip_protocol_deliver_rcu+0x8f/0x370 [ 286.493579][ C0] ip_local_deliver_finish+0x297/0x420 [ 286.494268][ C0] ip_local_deliver+0x168/0x430 [ 286.494867][ C0] ? __pfx_ip_local_deliver+0x10/0x10 [ 286.495498][ C0] ? __pfx_ip_local_deliver_finish+0x10/0x10 [ 286.496204][ C0] ? ip_rcv_finish_core+0x19a/0x1f20 [ 286.496806][ C0] ? lock_release+0x217/0x2c0 [ 286.497414][ C0] ip_rcv+0x455/0x6e0 [ 286.497945][ C0] ? __pfx_ip_rcv+0x10/0x10 [ ---truncated---

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In the Linux kernel, the following vulnerability has been resolved: btrfs: correct the order of prelim_ref arguments in btrfs__prelim_ref btrfs_prelim_ref() calls the old and new reference variables in the incorrect order. This causes a NULL pointer dereference because oldref is passed as NULL to trace_btrfs_prelim_ref_insert(). Note, trace_btrfs_prelim_ref_insert() is being called with newref as oldref (and oldref as NULL) on purpose in order to print out the values of newref. To reproduce: ... In the Linux kernel, the following vulnerability has been resolved: btrfs: correct the order of prelim_ref arguments in btrfs__prelim_ref btrfs_prelim_ref() calls the old and new reference variables in the incorrect order. This causes a NULL pointer dereference because oldref is passed as NULL to trace_btrfs_prelim_ref_insert(). Note, trace_btrfs_prelim_ref_insert() is being called with newref as oldref (and oldref as NULL) on purpose in order to print out the values of newref. To reproduce: echo 1 > /sys/kernel/debug/tracing/events/btrfs/btrfs_prelim_ref_insert/enable Perform some writeback operations. Backtrace: BUG: kernel NULL pointer dereference, address: 0000000000000018 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 115949067 P4D 115949067 PUD 11594a067 PMD 0 Oops: Oops: 0000 [#1] SMP NOPTI CPU: 1 UID: 0 PID: 1188 Comm: fsstress Not tainted 6.15.0-rc2-tester+ #47 PREEMPT(voluntary) 7ca2cef72d5e9c600f0c7718adb6462de8149622 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-2-gc13ff2cd-prebuilt.qemu.org 04/01/2014 RIP: 0010:trace_event_raw_event_btrfs__prelim_ref+0x72/0x130 Code: e8 43 81 9f ff 48 85 c0 74 78 4d 85 e4 0f 84 8f 00 00 00 49 8b 94 24 c0 06 00 00 48 8b 0a 48 89 48 08 48 8b 52 08 48 89 50 10 <49> 8b 55 18 48 89 50 18 49 8b 55 20 48 89 50 20 41 0f b6 55 28 88 RSP: 0018:ffffce44820077a0 EFLAGS: 00010286 RAX: ffff8c6b403f9014 RBX: ffff8c6b55825730 RCX: 304994edf9cf506b RDX: d8b11eb7f0fdb699 RSI: ffff8c6b403f9010 RDI: ffff8c6b403f9010 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000010 R10: 00000000ffffffff R11: 0000000000000000 R12: ffff8c6b4e8fb000 R13: 0000000000000000 R14: ffffce44820077a8 R15: ffff8c6b4abd1540 FS: 00007f4dc6813740(0000) GS:ffff8c6c1d378000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000018 CR3: 000000010eb42000 CR4: 0000000000750ef0 PKRU: 55555554 Call Trace: <TASK> prelim_ref_insert+0x1c1/0x270 find_parent_nodes+0x12a6/0x1ee0 ? __entry_text_end+0x101f06/0x101f09 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 btrfs_is_data_extent_shared+0x167/0x640 ? fiemap_process_hole+0xd0/0x2c0 extent_fiemap+0xa5c/0xbc0 ? __entry_text_end+0x101f05/0x101f09 btrfs_fiemap+0x7e/0xd0 do_vfs_ioctl+0x425/0x9d0 __x64_sys_ioctl+0x75/0xc0

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In the Linux kernel, the following vulnerability has been resolved: scsi: target: iscsi: Fix timeout on deleted connection NOPIN response timer may expire on a deleted connection and crash with such logs: Did not receive response to NOPIN on CID: 0, failing connection for I_T Nexus (null),i,0x00023d000125,iqn.2017-01.com.iscsi.target,t,0x3d BUG: Kernel NULL pointer dereference on read at 0x00000000 NIP strlcpy+0x8/0xb0 LR iscsit_fill_cxn_timeout_err_stats+0x5c/0xc0 [iscsi_target_mod] Call T ... In the Linux kernel, the following vulnerability has been resolved: scsi: target: iscsi: Fix timeout on deleted connection NOPIN response timer may expire on a deleted connection and crash with such logs: Did not receive response to NOPIN on CID: 0, failing connection for I_T Nexus (null),i,0x00023d000125,iqn.2017-01.com.iscsi.target,t,0x3d BUG: Kernel NULL pointer dereference on read at 0x00000000 NIP strlcpy+0x8/0xb0 LR iscsit_fill_cxn_timeout_err_stats+0x5c/0xc0 [iscsi_target_mod] Call Trace: iscsit_handle_nopin_response_timeout+0xfc/0x120 [iscsi_target_mod] call_timer_fn+0x58/0x1f0 run_timer_softirq+0x740/0x860 __do_softirq+0x16c/0x420 irq_exit+0x188/0x1c0 timer_interrupt+0x184/0x410 That is because nopin response timer may be re-started on nopin timer expiration. Stop nopin timer before stopping the nopin response timer to be sure that no one of them will be re-started.

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A NULL pointer dereference vulnerability has been reported to affect several QNAP operating system versions. The remote attackers can then exploit the vulnerability to launch a denial-of-service (DoS) attack. We have already fixed the vulnerability in the following versions: QTS 5.2.7.3297 build 20251024 and later QuTS hero h5.2.7.3297 build 20251024 and later QuTS hero h5.3.1.3292 build 20251024 and later

In the Linux kernel, the following vulnerability has been resolved: mm/huge_memory: fix dereferencing invalid pmd migration entry When migrating a THP, concurrent access to the PMD migration entry during a deferred split scan can lead to an invalid address access, as illustrated below. To prevent this invalid access, it is necessary to check the PMD migration entry and return early. In this context, there is no need to use pmd_to_swp_entry and pfn_swap_entry_to_page to verify the equality of ... In the Linux kernel, the following vulnerability has been resolved: mm/huge_memory: fix dereferencing invalid pmd migration entry When migrating a THP, concurrent access to the PMD migration entry during a deferred split scan can lead to an invalid address access, as illustrated below. To prevent this invalid access, it is necessary to check the PMD migration entry and return early. In this context, there is no need to use pmd_to_swp_entry and pfn_swap_entry_to_page to verify the equality of the target folio. Since the PMD migration entry is locked, it cannot be served as the target. Mailing list discussion and explanation from Hugh Dickins: "An anon_vma lookup points to a location which may contain the folio of interest, but might instead contain another folio: and weeding out those other folios is precisely what the "folio != pmd_folio((*pmd)" check (and the "risk of replacing the wrong folio" comment a few lines above it) is for." BUG: unable to handle page fault for address: ffffea60001db008 CPU: 0 UID: 0 PID: 2199114 Comm: tee Not tainted 6.14.0+ #4 NONE Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:split_huge_pmd_locked+0x3b5/0x2b60 Call Trace: <TASK> try_to_migrate_one+0x28c/0x3730 rmap_walk_anon+0x4f6/0x770 unmap_folio+0x196/0x1f0 split_huge_page_to_list_to_order+0x9f6/0x1560 deferred_split_scan+0xac5/0x12a0 shrinker_debugfs_scan_write+0x376/0x470 full_proxy_write+0x15c/0x220 vfs_write+0x2fc/0xcb0 ksys_write+0x146/0x250 do_syscall_64+0x6a/0x120 entry_SYSCALL_64_after_hwframe+0x76/0x7e The bug is found by syzkaller on an internal kernel, then confirmed on upstream.

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In the Linux kernel, the following vulnerability has been resolved: Input: mtk-pmic-keys - fix possible null pointer dereference In mtk_pmic_keys_probe, the regs parameter is only set if the button is parsed in the device tree. However, on hardware where the button is left floating, that node will most likely be removed not to enable that input. In that case the code will try to dereference a null pointer. Let's use the regs struct instead as it is defined for all supported platforms. Note th ... In the Linux kernel, the following vulnerability has been resolved: Input: mtk-pmic-keys - fix possible null pointer dereference In mtk_pmic_keys_probe, the regs parameter is only set if the button is parsed in the device tree. However, on hardware where the button is left floating, that node will most likely be removed not to enable that input. In that case the code will try to dereference a null pointer. Let's use the regs struct instead as it is defined for all supported platforms. Note that it is ok setting the key reg even if that latter is disabled as the interrupt won't be enabled anyway.

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In the Linux kernel, the following vulnerability has been resolved: usb: typec: ucsi: displayport: Fix NULL pointer access This patch ensures that the UCSI driver waits for all pending tasks in the ucsi_displayport_work workqueue to finish executing before proceeding with the partner removal.

In the Linux kernel, the following vulnerability has been resolved: net_sched: Flush gso_skb list too during ->change() Previously, when reducing a qdisc's limit via the ->change() operation, only the main skb queue was trimmed, potentially leaving packets in the gso_skb list. This could result in NULL pointer dereference when we only check sch->limit against sch->q.qlen. This patch introduces a new helper, qdisc_dequeue_internal(), which ensures both the gso_skb list and the main queue are p ... In the Linux kernel, the following vulnerability has been resolved: net_sched: Flush gso_skb list too during ->change() Previously, when reducing a qdisc's limit via the ->change() operation, only the main skb queue was trimmed, potentially leaving packets in the gso_skb list. This could result in NULL pointer dereference when we only check sch->limit against sch->q.qlen. This patch introduces a new helper, qdisc_dequeue_internal(), which ensures both the gso_skb list and the main queue are properly flushed when trimming excess packets. All relevant qdiscs (codel, fq, fq_codel, fq_pie, hhf, pie) are updated to use this helper in their ->change() routines.

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In the Linux kernel, the following vulnerability has been resolved: RDMA/mlx5: Initialize obj_event->obj_sub_list before xa_insert The obj_event may be loaded immediately after inserted, then if the list_head is not initialized then we may get a poisonous pointer. This fixes the crash below: mlx5_core 0000:03:00.0: MLX5E: StrdRq(1) RqSz(8) StrdSz(2048) RxCqeCmprss(0 enhanced) mlx5_core.sf mlx5_core.sf.4: firmware version: 32.38.3056 mlx5_core 0000:03:00.0 en3f0pf0sf2002: renamed from eth0 ... In the Linux kernel, the following vulnerability has been resolved: RDMA/mlx5: Initialize obj_event->obj_sub_list before xa_insert The obj_event may be loaded immediately after inserted, then if the list_head is not initialized then we may get a poisonous pointer. This fixes the crash below: mlx5_core 0000:03:00.0: MLX5E: StrdRq(1) RqSz(8) StrdSz(2048) RxCqeCmprss(0 enhanced) mlx5_core.sf mlx5_core.sf.4: firmware version: 32.38.3056 mlx5_core 0000:03:00.0 en3f0pf0sf2002: renamed from eth0 mlx5_core.sf mlx5_core.sf.4: Rate limit: 127 rates are supported, range: 0Mbps to 195312Mbps IPv6: ADDRCONF(NETDEV_CHANGE): en3f0pf0sf2002: link becomes ready Unable to handle kernel NULL pointer dereference at virtual address 0000000000000060 Mem abort info: ESR = 0x96000006 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000006 CM = 0, WnR = 0 user pgtable: 4k pages, 48-bit VAs, pgdp=00000007760fb000 [0000000000000060] pgd=000000076f6d7003, p4d=000000076f6d7003, pud=0000000777841003, pmd=0000000000000000 Internal error: Oops: 96000006 [#1] SMP Modules linked in: ipmb_host(OE) act_mirred(E) cls_flower(E) sch_ingress(E) mptcp_diag(E) udp_diag(E) raw_diag(E) unix_diag(E) tcp_diag(E) inet_diag(E) binfmt_misc(E) bonding(OE) rdma_ucm(OE) rdma_cm(OE) iw_cm(OE) ib_ipoib(OE) ib_cm(OE) isofs(E) cdrom(E) mst_pciconf(OE) ib_umad(OE) mlx5_ib(OE) ipmb_dev_int(OE) mlx5_core(OE) kpatch_15237886(OEK) mlxdevm(OE) auxiliary(OE) ib_uverbs(OE) ib_core(OE) psample(E) mlxfw(OE) tls(E) sunrpc(E) vfat(E) fat(E) crct10dif_ce(E) ghash_ce(E) sha1_ce(E) sbsa_gwdt(E) virtio_console(E) ext4(E) mbcache(E) jbd2(E) xfs(E) libcrc32c(E) mmc_block(E) virtio_net(E) net_failover(E) failover(E) sha2_ce(E) sha256_arm64(E) nvme(OE) nvme_core(OE) gpio_mlxbf3(OE) mlx_compat(OE) mlxbf_pmc(OE) i2c_mlxbf(OE) sdhci_of_dwcmshc(OE) pinctrl_mlxbf3(OE) mlxbf_pka(OE) gpio_generic(E) i2c_core(E) mmc_core(E) mlxbf_gige(OE) vitesse(E) pwr_mlxbf(OE) mlxbf_tmfifo(OE) micrel(E) mlxbf_bootctl(OE) virtio_ring(E) virtio(E) ipmi_devintf(E) ipmi_msghandler(E) [last unloaded: mst_pci] CPU: 11 PID: 20913 Comm: rte-worker-11 Kdump: loaded Tainted: G OE K 5.10.134-13.1.an8.aarch64 #1 Hardware name: https://www.mellanox.com BlueField-3 SmartNIC Main Card/BlueField-3 SmartNIC Main Card, BIOS 4.2.2.12968 Oct 26 2023 pstate: a0400089 (NzCv daIf +PAN -UAO -TCO BTYPE=--) pc : dispatch_event_fd+0x68/0x300 [mlx5_ib] lr : devx_event_notifier+0xcc/0x228 [mlx5_ib] sp : ffff80001005bcf0 x29: ffff80001005bcf0 x28: 0000000000000001 x27: ffff244e0740a1d8 x26: ffff244e0740a1d0 x25: ffffda56beff5ae0 x24: ffffda56bf911618 x23: ffff244e0596a480 x22: ffff244e0596a480 x21: ffff244d8312ad90 x20: ffff244e0596a480 x19: fffffffffffffff0 x18: 0000000000000000 x17: 0000000000000000 x16: ffffda56be66d620 x15: 0000000000000000 x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 x11: 0000000000000040 x10: ffffda56bfcafb50 x9 : ffffda5655c25f2c x8 : 0000000000000010 x7 : 0000000000000000 x6 : ffff24545a2e24b8 x5 : 0000000000000003 x4 : ffff80001005bd28 x3 : 0000000000000000 x2 : 0000000000000000 x1 : ffff244e0596a480 x0 : ffff244d8312ad90 Call trace: dispatch_event_fd+0x68/0x300 [mlx5_ib] devx_event_notifier+0xcc/0x228 [mlx5_ib] atomic_notifier_call_chain+0x58/0x80 mlx5_eq_async_int+0x148/0x2b0 [mlx5_core] atomic_notifier_call_chain+0x58/0x80 irq_int_handler+0x20/0x30 [mlx5_core] __handle_irq_event_percpu+0x60/0x220 handle_irq_event_percpu+0x3c/0x90 handle_irq_event+0x58/0x158 handle_fasteoi_irq+0xfc/0x188 generic_handle_irq+0x34/0x48 ...

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FFmpeg git master before commit c08d30 was discovered to contain a memory leak in the avformat_free_context function in libavutil/mem.c.

In the Linux kernel, the following vulnerability has been resolved: jffs2: check jffs2_prealloc_raw_node_refs() result in few other places Fuzzing hit another invalid pointer dereference due to the lack of checking whether jffs2_prealloc_raw_node_refs() completed successfully. Subsequent logic implies that the node refs have been allocated. Handle that. The code is ready for propagating the error upwards. KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] CPU: 1 PID: 5835 ... In the Linux kernel, the following vulnerability has been resolved: jffs2: check jffs2_prealloc_raw_node_refs() result in few other places Fuzzing hit another invalid pointer dereference due to the lack of checking whether jffs2_prealloc_raw_node_refs() completed successfully. Subsequent logic implies that the node refs have been allocated. Handle that. The code is ready for propagating the error upwards. KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] CPU: 1 PID: 5835 Comm: syz-executor145 Not tainted 5.10.234-syzkaller #0 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 RIP: 0010:jffs2_link_node_ref+0xac/0x690 fs/jffs2/nodelist.c:600 Call Trace: jffs2_mark_erased_block fs/jffs2/erase.c:460 [inline] jffs2_erase_pending_blocks+0x688/0x1860 fs/jffs2/erase.c:118 jffs2_garbage_collect_pass+0x638/0x1a00 fs/jffs2/gc.c:253 jffs2_reserve_space+0x3f4/0xad0 fs/jffs2/nodemgmt.c:167 jffs2_write_inode_range+0x246/0xb50 fs/jffs2/write.c:362 jffs2_write_end+0x712/0x1110 fs/jffs2/file.c:302 generic_perform_write+0x2c2/0x500 mm/filemap.c:3347 __generic_file_write_iter+0x252/0x610 mm/filemap.c:3465 generic_file_write_iter+0xdb/0x230 mm/filemap.c:3497 call_write_iter include/linux/fs.h:2039 [inline] do_iter_readv_writev+0x46d/0x750 fs/read_write.c:740 do_iter_write+0x18c/0x710 fs/read_write.c:866 vfs_writev+0x1db/0x6a0 fs/read_write.c:939 do_pwritev fs/read_write.c:1036 [inline] __do_sys_pwritev fs/read_write.c:1083 [inline] __se_sys_pwritev fs/read_write.c:1078 [inline] __x64_sys_pwritev+0x235/0x310 fs/read_write.c:1078 do_syscall_64+0x30/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x67/0xd1 Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

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In the Linux kernel, the following vulnerability has been resolved: jbd2: fix data-race and null-ptr-deref in jbd2_journal_dirty_metadata() Since handle->h_transaction may be a NULL pointer, so we should change it to call is_handle_aborted(handle) first before dereferencing it. And the following data-race was reported in my fuzzer: ================================================================== BUG: KCSAN: data-race in jbd2_journal_dirty_metadata / jbd2_journal_dirty_metadata write to 0x ... In the Linux kernel, the following vulnerability has been resolved: jbd2: fix data-race and null-ptr-deref in jbd2_journal_dirty_metadata() Since handle->h_transaction may be a NULL pointer, so we should change it to call is_handle_aborted(handle) first before dereferencing it. And the following data-race was reported in my fuzzer: ================================================================== BUG: KCSAN: data-race in jbd2_journal_dirty_metadata / jbd2_journal_dirty_metadata write to 0xffff888011024104 of 4 bytes by task 10881 on cpu 1: jbd2_journal_dirty_metadata+0x2a5/0x770 fs/jbd2/transaction.c:1556 __ext4_handle_dirty_metadata+0xe7/0x4b0 fs/ext4/ext4_jbd2.c:358 ext4_do_update_inode fs/ext4/inode.c:5220 [inline] ext4_mark_iloc_dirty+0x32c/0xd50 fs/ext4/inode.c:5869 __ext4_mark_inode_dirty+0xe1/0x450 fs/ext4/inode.c:6074 ext4_dirty_inode+0x98/0xc0 fs/ext4/inode.c:6103 .... read to 0xffff888011024104 of 4 bytes by task 10880 on cpu 0: jbd2_journal_dirty_metadata+0xf2/0x770 fs/jbd2/transaction.c:1512 __ext4_handle_dirty_metadata+0xe7/0x4b0 fs/ext4/ext4_jbd2.c:358 ext4_do_update_inode fs/ext4/inode.c:5220 [inline] ext4_mark_iloc_dirty+0x32c/0xd50 fs/ext4/inode.c:5869 __ext4_mark_inode_dirty+0xe1/0x450 fs/ext4/inode.c:6074 ext4_dirty_inode+0x98/0xc0 fs/ext4/inode.c:6103 .... value changed: 0x00000000 -> 0x00000001 ================================================================== This issue is caused by missing data-race annotation for jh->b_modified. Therefore, the missing annotation needs to be added.

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In the Linux kernel, the following vulnerability has been resolved: drm/v3d: Disable interrupts before resetting the GPU Currently, an interrupt can be triggered during a GPU reset, which can lead to GPU hangs and NULL pointer dereference in an interrupt context as shown in the following trace: [ 314.035040] Unable to handle kernel NULL pointer dereference at virtual address 00000000000000c0 [ 314.043822] Mem abort info: [ 314.046606] ESR = 0x0000000096000005 [ 314.050347] EC = 0x ... In the Linux kernel, the following vulnerability has been resolved: drm/v3d: Disable interrupts before resetting the GPU Currently, an interrupt can be triggered during a GPU reset, which can lead to GPU hangs and NULL pointer dereference in an interrupt context as shown in the following trace: [ 314.035040] Unable to handle kernel NULL pointer dereference at virtual address 00000000000000c0 [ 314.043822] Mem abort info: [ 314.046606] ESR = 0x0000000096000005 [ 314.050347] EC = 0x25: DABT (current EL), IL = 32 bits [ 314.055651] SET = 0, FnV = 0 [ 314.058695] EA = 0, S1PTW = 0 [ 314.061826] FSC = 0x05: level 1 translation fault [ 314.066694] Data abort info: [ 314.069564] ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000 [ 314.075039] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 314.080080] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 314.085382] user pgtable: 4k pages, 39-bit VAs, pgdp=0000000102728000 [ 314.091814] [00000000000000c0] pgd=0000000000000000, p4d=0000000000000000, pud=0000000000000000 [ 314.100511] Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP [ 314.106770] Modules linked in: v3d i2c_brcmstb vc4 snd_soc_hdmi_codec gpu_sched drm_shmem_helper drm_display_helper cec drm_dma_helper drm_kms_helper drm drm_panel_orientation_quirks snd_soc_core snd_compress snd_pcm_dmaengine snd_pcm snd_timer snd backlight [ 314.129654] CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.12.25+rpt-rpi-v8 #1 Debian 1:6.12.25-1+rpt1 [ 314.139388] Hardware name: Raspberry Pi 4 Model B Rev 1.4 (DT) [ 314.145211] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 314.152165] pc : v3d_irq+0xec/0x2e0 [v3d] [ 314.156187] lr : v3d_irq+0xe0/0x2e0 [v3d] [ 314.160198] sp : ffffffc080003ea0 [ 314.163502] x29: ffffffc080003ea0 x28: ffffffec1f184980 x27: 021202b000000000 [ 314.170633] x26: ffffffec1f17f630 x25: ffffff8101372000 x24: ffffffec1f17d9f0 [ 314.177764] x23: 000000000000002a x22: 000000000000002a x21: ffffff8103252000 [ 314.184895] x20: 0000000000000001 x19: 00000000deadbeef x18: 0000000000000000 [ 314.192026] x17: ffffff94e51d2000 x16: ffffffec1dac3cb0 x15: c306000000000000 [ 314.199156] x14: 0000000000000000 x13: b2fc982e03cc5168 x12: 0000000000000001 [ 314.206286] x11: ffffff8103f8bcc0 x10: ffffffec1f196868 x9 : ffffffec1dac3874 [ 314.213416] x8 : 0000000000000000 x7 : 0000000000042a3a x6 : ffffff810017a180 [ 314.220547] x5 : ffffffec1ebad400 x4 : ffffffec1ebad320 x3 : 00000000000bebeb [ 314.227677] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000 [ 314.234807] Call trace: [ 314.237243] v3d_irq+0xec/0x2e0 [v3d] [ 314.240906] __handle_irq_event_percpu+0x58/0x218 [ 314.245609] handle_irq_event+0x54/0xb8 [ 314.249439] handle_fasteoi_irq+0xac/0x240 [ 314.253527] handle_irq_desc+0x48/0x68 [ 314.257269] generic_handle_domain_irq+0x24/0x38 [ 314.261879] gic_handle_irq+0x48/0xd8 [ 314.265533] call_on_irq_stack+0x24/0x58 [ 314.269448] do_interrupt_handler+0x88/0x98 [ 314.273624] el1_interrupt+0x34/0x68 [ 314.277193] el1h_64_irq_handler+0x18/0x28 [ 314.281281] el1h_64_irq+0x64/0x68 [ 314.284673] default_idle_call+0x3c/0x168 [ 314.288675] do_idle+0x1fc/0x230 [ 314.291895] cpu_startup_entry+0x3c/0x50 [ 314.295810] rest_init+0xe4/0xf0 [ 314.299030] start_kernel+0x5e8/0x790 [ 314.302684] __primary_switched+0x80/0x90 [ 314.306691] Code: 940029eb 360ffc13 f9442ea0 52800001 (f9406017) [ 314.312775] ---[ end trace 0000000000000000 ]--- [ 314.317384] Kernel panic - not syncing: Oops: Fatal exception in interrupt [ 314.324249] SMP: stopping secondary CPUs [ 314.328167] Kernel Offset: 0x2b9da00000 from 0xffffffc080000000 [ 314.334076] PHYS_OFFSET: 0x0 [ 314.336946] CPU features: 0x08,00002013,c0200000,0200421b [ 314.342337] Memory Limit: none [ 314.345382] ---[ end Kernel panic - not syncing: Oops: Fatal exception in interrupt ]--- Before resetting the G ---truncated---

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In the Linux kernel, the following vulnerability has been resolved: dma-buf: insert memory barrier before updating num_fences smp_store_mb() inserts memory barrier after storing operation. It is different with what the comment is originally aiming so Null pointer dereference can be happened if memory update is reordered.

In the Linux kernel, the following vulnerability has been resolved: x86/iopl: Cure TIF_IO_BITMAP inconsistencies io_bitmap_exit() is invoked from exit_thread() when a task exists or when a fork fails. In the latter case the exit_thread() cleans up resources which were allocated during fork(). io_bitmap_exit() invokes task_update_io_bitmap(), which in turn ends up in tss_update_io_bitmap(). tss_update_io_bitmap() operates on the current task. If current has TIF_IO_BITMAP set, but no bitmap ins ... In the Linux kernel, the following vulnerability has been resolved: x86/iopl: Cure TIF_IO_BITMAP inconsistencies io_bitmap_exit() is invoked from exit_thread() when a task exists or when a fork fails. In the latter case the exit_thread() cleans up resources which were allocated during fork(). io_bitmap_exit() invokes task_update_io_bitmap(), which in turn ends up in tss_update_io_bitmap(). tss_update_io_bitmap() operates on the current task. If current has TIF_IO_BITMAP set, but no bitmap installed, tss_update_io_bitmap() crashes with a NULL pointer dereference. There are two issues, which lead to that problem: 1) io_bitmap_exit() should not invoke task_update_io_bitmap() when the task, which is cleaned up, is not the current task. That's a clear indicator for a cleanup after a failed fork(). 2) A task should not have TIF_IO_BITMAP set and neither a bitmap installed nor IOPL emulation level 3 activated. This happens when a kernel thread is created in the context of a user space thread, which has TIF_IO_BITMAP set as the thread flags are copied and the IO bitmap pointer is cleared. Other than in the failed fork() case this has no impact because kernel threads including IO workers never return to user space and therefore never invoke tss_update_io_bitmap(). Cure this by adding the missing cleanups and checks: 1) Prevent io_bitmap_exit() to invoke task_update_io_bitmap() if the to be cleaned up task is not the current task. 2) Clear TIF_IO_BITMAP in copy_thread() unconditionally. For user space forks it is set later, when the IO bitmap is inherited in io_bitmap_share(). For paranoia sake, add a warning into tss_update_io_bitmap() to catch the case, when that code is invoked with inconsistent state.

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In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Add null pointer check for get_first_active_display() The function mod_hdcp_hdcp1_enable_encryption() calls the function get_first_active_display(), but does not check its return value. The return value is a null pointer if the display list is empty. This will lead to a null pointer dereference in mod_hdcp_hdcp2_enable_encryption(). Add a null pointer check for get_first_active_display() and return MOD_HDCP_S ... In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Add null pointer check for get_first_active_display() The function mod_hdcp_hdcp1_enable_encryption() calls the function get_first_active_display(), but does not check its return value. The return value is a null pointer if the display list is empty. This will lead to a null pointer dereference in mod_hdcp_hdcp2_enable_encryption(). Add a null pointer check for get_first_active_display() and return MOD_HDCP_STATUS_DISPLAY_NOT_FOUND if the function return null.

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In the Linux kernel, the following vulnerability has been resolved: drm/tegra: Fix a possible null pointer dereference In tegra_crtc_reset(), new memory is allocated with kzalloc(), but no check is performed. Before calling __drm_atomic_helper_crtc_reset, state should be checked to prevent possible null pointer dereference.

In the Linux kernel, the following vulnerability has been resolved: maple_tree: fix MA_STATE_PREALLOC flag in mas_preallocate() Temporarily clear the preallocation flag when explicitly requesting allocations. Pre-existing allocations are already counted against the request through mas_node_count_gfp(), but the allocations will not happen if the MA_STATE_PREALLOC flag is set. This flag is meant to avoid re-allocating in bulk allocation mode, and to detect issues with preallocation calculation ... In the Linux kernel, the following vulnerability has been resolved: maple_tree: fix MA_STATE_PREALLOC flag in mas_preallocate() Temporarily clear the preallocation flag when explicitly requesting allocations. Pre-existing allocations are already counted against the request through mas_node_count_gfp(), but the allocations will not happen if the MA_STATE_PREALLOC flag is set. This flag is meant to avoid re-allocating in bulk allocation mode, and to detect issues with preallocation calculations. The MA_STATE_PREALLOC flag should also always be set on zero allocations so that detection of underflow allocations will print a WARN_ON() during consumption. User visible effect of this flaw is a WARN_ON() followed by a null pointer dereference when subsequent requests for larger number of nodes is ignored, such as the vma merge retry in mmap_region() caused by drivers altering the vma flags (which happens in v6.6, at least)

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Null pointer dereference in Windows Client-Side Caching (CSC) Service allows an authorized attacker to elevate privileges locally.

Suricata is a network IDS, IPS and NSM engine developed by the OISF (Open Information Security Foundation) and the Suricata community. In versions from 8.0.0 to before 8.0.2, a NULL dereference can occur when the entropy keyword is used in conjunction with base64_data. This issue has been patched in version 8.0.2. A workaround involves disabling rules that use entropy in conjunction with base64_data.

Null pointer dereference in add_ca_certs() in Cesanta Mongoose before 7.2 allows remote attackers to cause a denial of service via TLS initialization where SSL_CTX_get_cert_store() returns NULL.

A NULL pointer dereference vulnerability in the util.readFileIntoStream component of PDF-XChange Editor v10.7.3.401 allows attackers to cause a Denial of Service (DoS) via a crafted input.

A NULL pointer dereference vulnerability in the importDataObject() function of PDF-XChange Editor v10.7.3.401 allows attackers to cause a Denial of Service (DoS) via a crafted input.

Null pointer dereference in Windows DirectX allows an authorized attacker to deny service locally.

Null pointer dereference in Windows DirectX allows an authorized attacker to deny service locally.

In the Linux kernel, the following vulnerability has been resolved: jfs: fix GPF in diFree Avoid passing inode with JFS_SBI(inode->i_sb)->ipimap == NULL to diFree()[1]. GFP will appear: struct inode *ipimap = JFS_SBI(ip->i_sb)->ipimap; struct inomap *imap = JFS_IP(ipimap)->i_imap; JFS_IP() will return invalid pointer when ipimap == NULL Call Trace: diFree+0x13d/0x2dc0 fs/jfs/jfs_imap.c:853 [1] jfs_evict_inode+0x2c9/0x370 fs/jfs/inode.c:154 evict+0x2ed/0x750 fs/inode.c:578 iput_final f ... In the Linux kernel, the following vulnerability has been resolved: jfs: fix GPF in diFree Avoid passing inode with JFS_SBI(inode->i_sb)->ipimap == NULL to diFree()[1]. GFP will appear: struct inode *ipimap = JFS_SBI(ip->i_sb)->ipimap; struct inomap *imap = JFS_IP(ipimap)->i_imap; JFS_IP() will return invalid pointer when ipimap == NULL Call Trace: diFree+0x13d/0x2dc0 fs/jfs/jfs_imap.c:853 [1] jfs_evict_inode+0x2c9/0x370 fs/jfs/inode.c:154 evict+0x2ed/0x750 fs/inode.c:578 iput_final fs/inode.c:1654 [inline] iput.part.0+0x3fe/0x820 fs/inode.c:1680 iput+0x58/0x70 fs/inode.c:1670

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NULL Pointer Dereference vulnerability in ravynsoft ravynos.This issue affects ravynos: through 0.5.2.

An issue was discovered in AnyDesk for Windows before 9.0.5, AnyDesk for macOS before 9.0.1, AnyDesk for Linux before 7.0.0, AnyDesk for iOS before 7.1.2, and AnyDesk for Android before 8.0.0. Remote Denial of Service can occur because of incorrect deserialization that results in failed memory allocation and a NULL pointer dereference.

An issue was discovered in Camera in Samsung Mobile Processor Exynos 1280 and 2200. Unnecessary registration of a hardware IP address in the Camera device driver can lead to a NULL pointer dereference, resulting in a denial of service.

Envoy is a high-performance edge/middle/service proxy. In 1.33.12, 1.34.10, 1.35.6, 1.36.2, and earlier, Envoy crashes when JWT authentication is configured with the remote JWKS fetching, allow_missing_or_failed is enabled, multiple JWT tokens are present in the request headers and the JWKS fetch fails. This is caused by a re-entry bug in the JwksFetcherImpl. When the first token's JWKS fetch fails, onJwksError() callback triggers processing of the second token, which calls fetch() again on the ... Envoy is a high-performance edge/middle/service proxy. In 1.33.12, 1.34.10, 1.35.6, 1.36.2, and earlier, Envoy crashes when JWT authentication is configured with the remote JWKS fetching, allow_missing_or_failed is enabled, multiple JWT tokens are present in the request headers and the JWKS fetch fails. This is caused by a re-entry bug in the JwksFetcherImpl. When the first token's JWKS fetch fails, onJwksError() callback triggers processing of the second token, which calls fetch() again on the same fetcher object. The original callback's reset() then clears the second fetch's state (receiver_ and request_) which causes a crash when the async HTTP response arrives.

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SSH dissector crash in Wireshark 4.4.0 to 4.4.8 allows denial of service

Omni manages Kubernetes on bare metal, virtual machines, or in a cloud. Prior to 1.1.5 and 1.0.2, there is a nil pointer dereference vulnerability in the Omni Resource Service allows unauthenticated users to cause a server panic and denial of service by sending empty create/update resource requests through the API endpoints. The vulnerability exists in the isSensitiveSpec function which calls grpcomni.CreateResource without checking if the resource's metadata field is nil. When a resource is cre ... Omni manages Kubernetes on bare metal, virtual machines, or in a cloud. Prior to 1.1.5 and 1.0.2, there is a nil pointer dereference vulnerability in the Omni Resource Service allows unauthenticated users to cause a server panic and denial of service by sending empty create/update resource requests through the API endpoints. The vulnerability exists in the isSensitiveSpec function which calls grpcomni.CreateResource without checking if the resource's metadata field is nil. When a resource is created with an empty Metadata field, the CreateResource function attempts to access resource.Metadata.Version causing a segmentation fault. This vulnerability is fixed in 1.1.5 and 1.0.2.

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In the Linux kernel, the following vulnerability has been resolved: io_uring/msg_ring: Fix NULL pointer dereference in io_msg_send_fd() Syzkaller produced the below call trace: BUG: KASAN: null-ptr-deref in io_msg_ring+0x3cb/0x9f0 Write of size 8 at addr 0000000000000070 by task repro/16399 CPU: 0 PID: 16399 Comm: repro Not tainted 6.1.0-rc1 #28 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 Call Trace: <TASK> dump_stack_lvl+0xcd/0x134 ? io_msg_ring+0x3cb ... In the Linux kernel, the following vulnerability has been resolved: io_uring/msg_ring: Fix NULL pointer dereference in io_msg_send_fd() Syzkaller produced the below call trace: BUG: KASAN: null-ptr-deref in io_msg_ring+0x3cb/0x9f0 Write of size 8 at addr 0000000000000070 by task repro/16399 CPU: 0 PID: 16399 Comm: repro Not tainted 6.1.0-rc1 #28 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 Call Trace: <TASK> dump_stack_lvl+0xcd/0x134 ? io_msg_ring+0x3cb/0x9f0 kasan_report+0xbc/0xf0 ? io_msg_ring+0x3cb/0x9f0 kasan_check_range+0x140/0x190 io_msg_ring+0x3cb/0x9f0 ? io_msg_ring_prep+0x300/0x300 io_issue_sqe+0x698/0xca0 io_submit_sqes+0x92f/0x1c30 __do_sys_io_uring_enter+0xae4/0x24b0 .... RIP: 0033:0x7f2eaf8f8289 RSP: 002b:00007fff40939718 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f2eaf8f8289 RDX: 0000000000000000 RSI: 0000000000006f71 RDI: 0000000000000004 RBP: 00007fff409397a0 R08: 0000000000000000 R09: 0000000000000039 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004006d0 R13: 00007fff40939880 R14: 0000000000000000 R15: 0000000000000000 </TASK> Kernel panic - not syncing: panic_on_warn set ... We don't have a NULL check on file_ptr in io_msg_send_fd() function, so when file_ptr is NUL src_file is also NULL and get_file() dereferences a NULL pointer and leads to above crash. Add a NULL check to fix this issue.

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The gmp plugin in strongSwan before 5.6.0 allows remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) via a crafted RSA signature.

In the Linux kernel, the following vulnerability has been resolved: ASoC: qcom: Add checks for devm_kcalloc As the devm_kcalloc may return NULL, the return value needs to be checked to avoid NULL poineter dereference.

In the Linux kernel, the following vulnerability has been resolved: drm/bridge: megachips: Fix a null pointer dereference bug When removing the module we will get the following warning: [ 31.911505] i2c-core: driver [stdp2690-ge-b850v3-fw] unregistered [ 31.912484] general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN PTI [ 31.913338] KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] [ 31.915280] RIP: 0010:drm ... In the Linux kernel, the following vulnerability has been resolved: drm/bridge: megachips: Fix a null pointer dereference bug When removing the module we will get the following warning: [ 31.911505] i2c-core: driver [stdp2690-ge-b850v3-fw] unregistered [ 31.912484] general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN PTI [ 31.913338] KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] [ 31.915280] RIP: 0010:drm_bridge_remove+0x97/0x130 [ 31.921825] Call Trace: [ 31.922533] stdp4028_ge_b850v3_fw_remove+0x34/0x60 [megachips_stdpxxxx_ge_b850v3_fw] [ 31.923139] i2c_device_remove+0x181/0x1f0 The two bridges (stdp2690, stdp4028) do not probe at the same time, so the driver does not call ge_b850v3_resgiter() when probing, causing the driver to try to remove the object that has not been initialized. Fix this by checking whether both the bridges are probed.

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In the Linux kernel, the following vulnerability has been resolved: wifi: mt76: mt7996: rely on mt76_connac2_mac_tx_rate_val In order to fix a possible NULL pointer dereference in mt7996_mac_write_txwi() of vif pointer, export mt76_connac2_mac_tx_rate_val utility routine and reuse it in mt7996 driver.

In the Linux kernel, the following vulnerability has been resolved: hwmon: (pmbus_core) Fix NULL pointer dereference Pass i2c_client to _pmbus_is_enabled to drop the assumption that a regulator device is passed in. This will fix the issue of a NULL pointer dereference when called from _pmbus_get_flags.

In the Linux kernel, the following vulnerability has been resolved: pnode: terminate at peers of source The propagate_mnt() function handles mount propagation when creating mounts and propagates the source mount tree @source_mnt to all applicable nodes of the destination propagation mount tree headed by @dest_mnt. Unfortunately it contains a bug where it fails to terminate at peers of @source_mnt when looking up copies of the source mount that become masters for copies of the source mount tre ... In the Linux kernel, the following vulnerability has been resolved: pnode: terminate at peers of source The propagate_mnt() function handles mount propagation when creating mounts and propagates the source mount tree @source_mnt to all applicable nodes of the destination propagation mount tree headed by @dest_mnt. Unfortunately it contains a bug where it fails to terminate at peers of @source_mnt when looking up copies of the source mount that become masters for copies of the source mount tree mounted on top of slaves in the destination propagation tree causing a NULL dereference. Once the mechanics of the bug are understood it's easy to trigger. Because of unprivileged user namespaces it is available to unprivileged users. While fixing this bug we've gotten confused multiple times due to unclear terminology or missing concepts. So let's start this with some clarifications: * The terms "master" or "peer" denote a shared mount. A shared mount belongs to a peer group. * A peer group is a set of shared mounts that propagate to each other. They are identified by a peer group id. The peer group id is available in @shared_mnt->mnt_group_id. Shared mounts within the same peer group have the same peer group id. The peers in a peer group can be reached via @shared_mnt->mnt_share. * The terms "slave mount" or "dependent mount" denote a mount that receives propagation from a peer in a peer group. IOW, shared mounts may have slave mounts and slave mounts have shared mounts as their master. Slave mounts of a given peer in a peer group are listed on that peers slave list available at @shared_mnt->mnt_slave_list. * The term "master mount" denotes a mount in a peer group. IOW, it denotes a shared mount or a peer mount in a peer group. The term "master mount" - or "master" for short - is mostly used when talking in the context of slave mounts that receive propagation from a master mount. A master mount of a slave identifies the closest peer group a slave mount receives propagation from. The master mount of a slave can be identified via @slave_mount->mnt_master. Different slaves may point to different masters in the same peer group. * Multiple peers in a peer group can have non-empty ->mnt_slave_lists. Non-empty ->mnt_slave_lists of peers don't intersect. Consequently, to ensure all slave mounts of a peer group are visited the ->mnt_slave_lists of all peers in a peer group have to be walked. * Slave mounts point to a peer in the closest peer group they receive propagation from via @slave_mnt->mnt_master (see above). Together with these peers they form a propagation group (see below). The closest peer group can thus be identified through the peer group id @slave_mnt->mnt_master->mnt_group_id of the peer/master that a slave mount receives propagation from. * A shared-slave mount is a slave mount to a peer group pg1 while also a peer in another peer group pg2. IOW, a peer group may receive propagation from another peer group. If a peer group pg1 is a slave to another peer group pg2 then all peers in peer group pg1 point to the same peer in peer group pg2 via ->mnt_master. IOW, all peers in peer group pg1 appear on the same ->mnt_slave_list. IOW, they cannot be slaves to different peer groups. * A pure slave mount is a slave mount that is a slave to a peer group but is not a peer in another peer group. * A propagation group denotes the set of mounts consisting of a single peer group pg1 and all slave mounts and shared-slave mounts that point to a peer in that peer group via ->mnt_master. IOW, all slave mounts such that @slave_mnt->mnt_master->mnt_group_id is equal to @shared_mnt->mnt_group_id. The concept of a propagation group makes it easier to talk about a single propagation level in a propagation tree. For example, in propagate_mnt() the immediate peers of @dest_mnt and all slaves of @dest_mnt's peer group form a propagation group pr ---truncated---

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