{"id":"CVE-2024-56559","url":"https://www.cyber-defence.io/tools/cve/CVE-2024-56559","generatedAt":"2026-10-28T03:30:18.139Z","title":"In the Linux kernel, the following vulnerability has been resolved: mm/vmalloc: combine all TLB flush operations of KASAN shadow virtual address into one operation When compiling kernel source 'make -j $(nproc)' with the up-and-running KASAN-enabled…","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/vmalloc: combine all TLB flush operations of KASAN shadow virtual address into one operation\n\nWhen compiling kernel source 'make -j $(nproc)' with the up-and-running\nKASAN-enabled kernel on a 256-core machine, the following soft lockup is\nshown:\n\nwatchdog: BUG: soft lockup - CPU#28 stuck for 22s! [kworker/28:1:1760]\nCPU: 28 PID: 1760 Comm: kworker/28:1 Kdump: loaded Not tainted 6.10.0-rc5 #95\nWorkqueue: events drain_vmap_area_work\nRIP: 0010:smp_call_function_many_cond+0x1d8/0xbb0\nCode: 38 c8 7c 08 84 c9 0f 85 49 08 00 00 8b 45 08 a8 01 74 2e 48 89 f1 49 89 f7 48 c1 e9 03 41 83 e7 07 4c 01 e9 41 83 c7 03 f3 90 <0f> b6 01 41 38 c7 7c 08 84 c0 0f 85 d4 06 00 00 8b 45 08 a8 01 75\nRSP: 0018:ffffc9000cb3fb60 EFLAGS: 00000202\nRAX: 0000000000000011 RBX: ffff8883bc4469c0 RCX: ffffed10776e9949\nRDX: 0000000000000002 RSI: ffff8883bb74ca48 RDI: ffffffff8434dc50\nRBP: ffff8883bb74ca40 R08: ffff888103585dc0 R09: ffff8884533a1800\nR10: 0000000000000004 R11: ffffffffffffffff R12: ffffed1077888d39\nR13: dffffc0000000000 R14: ffffed1077888d38 R15: 0000000000000003\nFS:  0000000000000000(0000) GS:ffff8883bc400000(0000) knlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 00005577b5c8d158 CR3: 0000000004850000 CR4: 0000000000350ef0\nCall Trace:\n <IRQ>\n ? watchdog_timer_fn+0x2cd/0x390\n ? __pfx_watchdog_timer_fn+0x10/0x10\n ? __hrtimer_run_queues+0x300/0x6d0\n ? sched_clock_cpu+0x69/0x4e0\n ? __pfx___hrtimer_run_queues+0x10/0x10\n ? srso_return_thunk+0x5/0x5f\n ? ktime_get_update_offsets_now+0x7f/0x2a0\n ? srso_return_thunk+0x5/0x5f\n ? srso_return_thunk+0x5/0x5f\n ? hrtimer_interrupt+0x2ca/0x760\n ? __sysvec_apic_timer_interrupt+0x8c/0x2b0\n ? sysvec_apic_timer_interrupt+0x6a/0x90\n </IRQ>\n <TASK>\n ? asm_sysvec_apic_timer_interrupt+0x16/0x20\n ? smp_call_function_many_cond+0x1d8/0xbb0\n ? __pfx_do_kernel_range_flush+0x10/0x10\n on_each_cpu_cond_mask+0x20/0x40\n flush_tlb_kernel_range+0x19b/0x250\n ? srso_return_thunk+0x5/0x5f\n ? kasan_release_vmalloc+0xa7/0xc0\n purge_vmap_node+0x357/0x820\n ? __pfx_purge_vmap_node+0x10/0x10\n __purge_vmap_area_lazy+0x5b8/0xa10\n drain_vmap_area_work+0x21/0x30\n process_one_work+0x661/0x10b0\n worker_thread+0x844/0x10e0\n ? srso_return_thunk+0x5/0x5f\n ? __kthread_parkme+0x82/0x140\n ? __pfx_worker_thread+0x10/0x10\n kthread+0x2a5/0x370\n ? __pfx_kthread+0x10/0x10\n ret_from_fork+0x30/0x70\n ? __pfx_kthread+0x10/0x10\n ret_from_fork_asm+0x1a/0x30\n </TASK>\n\nDebugging Analysis:\n\n  1. The following ftrace log shows that the lockup CPU spends too much\n     time iterating vmap_nodes and flushing TLB when purging vm_area\n     structures. (Some info is trimmed).\n\n     kworker: funcgraph_entry:              |  drain_vmap_area_work() {\n     kworker: funcgraph_entry:              |   mutex_lock() {\n     kworker: funcgraph_entry:  1.092 us    |     __cond_resched();\n     kworker: funcgraph_exit:   3.306 us    |   }\n     ...                                        ...\n     kworker: funcgraph_entry:              |    flush_tlb_kernel_range() {\n     ...                                          ...\n     kworker: funcgraph_exit: # 7533.649 us |    }\n     ...                                         ...\n     kworker: funcgraph_entry:  2.344 us    |   mutex_unlock();\n     kworker: funcgraph_exit: $ 23871554 us | }\n\n     The drain_vmap_area_work() spends over 23 seconds.\n\n     There are 2805 flush_tlb_kernel_range() calls in the ftrace log.\n       * One is called in __purge_vmap_area_lazy().\n       * Others are called by purge_vmap_node->kasan_release_vmalloc.\n         purge_vmap_node() iteratively releases kasan vmalloc\n         allocations and flushes TLB for each vmap_area.\n           - [Rough calculation] Each flush_tlb_kernel_range() runs\n             about 7.5ms.\n               -- 2804 * 7.5ms = 21.03 seconds.\n               -- That's why a soft lock is triggered.\n\n  2. Extending the soft lockup time can work around the issue (For example,\n     # echo\n---truncated---","published":"2024-12-27T15:15:15.000Z","lastModified":"2026-06-17T08:12:24.000Z","status":"Analyzed","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","cvss":{"version":"3.1","score":5.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-667"],"affected":["linux/linux kernel"],"epss":{"score":0.00145,"percentile":0.0375,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.14%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://git.kernel.org/stable/c/9e9e085effe9b7e342138fde3cf8577d22509932","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/f9a18889aad9b4c19c6c4550c67ad4f9ed2a354f","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2024-56559","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}