{"dataType":"CVE_RECORD","dataVersion":"5.1","cveMetadata":{"cveId":"CVE-2024-46797","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2024-09-11T15:12:18.280Z","datePublished":"2024-09-18T07:12:51.795Z","dateUpdated":"2025-05-04T09:34:33.179Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2025-05-04T09:34:33.179Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\npowerpc/qspinlock: Fix deadlock in MCS queue\n\nIf an interrupt occurs in queued_spin_lock_slowpath() after we increment\nqnodesp->count and before node->lock is initialized, another CPU might\nsee stale lock values in get_tail_qnode(). If the stale lock value happens\nto match the lock on that CPU, then we write to the \"next\" pointer of\nthe wrong qnode. This causes a deadlock as the former CPU, once it becomes\nthe head of the MCS queue, will spin indefinitely until it's \"next\" pointer\nis set by its successor in the queue.\n\nRunning stress-ng on a 16 core (16EC/16VP) shared LPAR, results in\noccasional lockups similar to the following:\n\n $ stress-ng --all 128 --vm-bytes 80% --aggressive \\\n --maximize --oomable --verify --syslog \\\n --metrics --times --timeout 5m\n\n watchdog: CPU 15 Hard LOCKUP\n ......\n NIP [c0000000000b78f4] queued_spin_lock_slowpath+0x1184/0x1490\n LR [c000000001037c5c] _raw_spin_lock+0x6c/0x90\n Call Trace:\n 0xc000002cfffa3bf0 (unreliable)\n _raw_spin_lock+0x6c/0x90\n raw_spin_rq_lock_nested.part.135+0x4c/0xd0\n sched_ttwu_pending+0x60/0x1f0\n __flush_smp_call_function_queue+0x1dc/0x670\n smp_ipi_demux_relaxed+0xa4/0x100\n xive_muxed_ipi_action+0x20/0x40\n __handle_irq_event_percpu+0x80/0x240\n handle_irq_event_percpu+0x2c/0x80\n handle_percpu_irq+0x84/0xd0\n generic_handle_irq+0x54/0x80\n __do_irq+0xac/0x210\n __do_IRQ+0x74/0xd0\n 0x0\n do_IRQ+0x8c/0x170\n hardware_interrupt_common_virt+0x29c/0x2a0\n --- interrupt: 500 at queued_spin_lock_slowpath+0x4b8/0x1490\n ......\n NIP [c0000000000b6c28] queued_spin_lock_slowpath+0x4b8/0x1490\n LR [c000000001037c5c] _raw_spin_lock+0x6c/0x90\n --- interrupt: 500\n 0xc0000029c1a41d00 (unreliable)\n _raw_spin_lock+0x6c/0x90\n futex_wake+0x100/0x260\n do_futex+0x21c/0x2a0\n sys_futex+0x98/0x270\n system_call_exception+0x14c/0x2f0\n system_call_vectored_common+0x15c/0x2ec\n\nThe following code flow illustrates how the deadlock occurs.\nFor the sake of brevity, assume that both locks (A and B) are\ncontended and we call the queued_spin_lock_slowpath() function.\n\n CPU0 CPU1\n ---- ----\n spin_lock_irqsave(A) |\n spin_unlock_irqrestore(A) |\n spin_lock(B) |\n | |\n ▼ |\n id = qnodesp->count++; |\n (Note that nodes[0].lock == A) |\n | |\n ▼ |\n Interrupt |\n (happens before \"nodes[0].lock = B\") |\n | |\n ▼ |\n spin_lock_irqsave(A) |\n | |\n ▼ |\n id = qnodesp->count++ |\n nodes[1].lock = A |\n | |\n ▼ |\n Tail of MCS queue |\n | spin_lock_irqsave(A)\n ▼ |\n Head of MCS queue ▼\n | CPU0 is previous tail\n ▼ |\n Spin indefinitely ▼\n (until \"nodes[1].next != NULL\") prev = get_tail_qnode(A, CPU0)\n |\n ▼\n prev == &qnodes[CPU0].nodes[0]\n (as qnodes\n---truncated---"}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/powerpc/lib/qspinlock.c"],"versions":[{"version":"84990b169557428c318df87b7836cd15f65b62dc","lessThan":"d84ab6661e8d09092de9b034b016515ef9b66085","status":"affected","versionType":"git"},{"version":"84990b169557428c318df87b7836cd15f65b62dc","lessThan":"f06af737e4be28c0e926dc25d5f0a111da4e2987","status":"affected","versionType":"git"},{"version":"84990b169557428c318df87b7836cd15f65b62dc","lessThan":"734ad0af3609464f8f93e00b6c0de1e112f44559","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/powerpc/lib/qspinlock.c"],"versions":[{"version":"6.2","status":"affected"},{"version":"0","lessThan":"6.2","status":"unaffected","versionType":"semver"},{"version":"6.6.51","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.10.10","lessThanOrEqual":"6.10.*","status":"unaffected","versionType":"semver"},{"version":"6.11","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.2","versionEndExcluding":"6.6.51"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.2","versionEndExcluding":"6.10.10"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.2","versionEndExcluding":"6.11"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/d84ab6661e8d09092de9b034b016515ef9b66085"},{"url":"https://git.kernel.org/stable/c/f06af737e4be28c0e926dc25d5f0a111da4e2987"},{"url":"https://git.kernel.org/stable/c/734ad0af3609464f8f93e00b6c0de1e112f44559"}],"title":"powerpc/qspinlock: Fix deadlock in MCS queue","x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2024-09-29T14:22:25.653688Z","id":"CVE-2024-46797","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2024-09-29T14:22:38.796Z"}}]}}