CVE-2025-21809 (GCVE-0-2025-21809)
Vulnerability from cvelistv5
Published
2025-02-27 20:01
Modified
2026-08-05 11:54
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: rxrpc, afs: Fix peer hash locking vs RCU callback In its address list, afs now retains pointers to and refs on one or more rxrpc_peer objects. The address list is freed under RCU and at this time, it puts the refs on those peers. Now, when an rxrpc_peer object runs out of refs, it gets removed from the peer hash table and, for that, rxrpc has to take a spinlock. However, it is now being called from afs's RCU cleanup, which takes place in BH context - but it is just taking an ordinary spinlock. The put may also be called from non-BH context, and so there exists the possibility of deadlock if the BH-based RCU cleanup happens whilst the hash spinlock is held. This led to the attached lockdep complaint. Fix this by changing spinlocks of rxnet->peer_hash_lock back to BH-disabling locks. ================================ WARNING: inconsistent lock state 6.13.0-rc5-build2+ #1223 Tainted: G E -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. swapper/1/0 [HC0[0]:SC1[1]:HE1:SE0] takes: ffff88810babe228 (&rxnet->peer_hash_lock){+.?.}-{3:3}, at: rxrpc_put_peer+0xcb/0x180 {SOFTIRQ-ON-W} state was registered at: mark_usage+0x164/0x180 __lock_acquire+0x544/0x990 lock_acquire.part.0+0x103/0x280 _raw_spin_lock+0x2f/0x40 rxrpc_peer_keepalive_worker+0x144/0x440 process_one_work+0x486/0x7c0 process_scheduled_works+0x73/0x90 worker_thread+0x1c8/0x2a0 kthread+0x19b/0x1b0 ret_from_fork+0x24/0x40 ret_from_fork_asm+0x1a/0x30 irq event stamp: 972402 hardirqs last enabled at (972402): [<ffffffff8244360e>] _raw_spin_unlock_irqrestore+0x2e/0x50 hardirqs last disabled at (972401): [<ffffffff82443328>] _raw_spin_lock_irqsave+0x18/0x60 softirqs last enabled at (972300): [<ffffffff810ffbbe>] handle_softirqs+0x3ee/0x430 softirqs last disabled at (972313): [<ffffffff810ffc54>] __irq_exit_rcu+0x44/0x110 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&rxnet->peer_hash_lock); <Interrupt> lock(&rxnet->peer_hash_lock); *** DEADLOCK *** 1 lock held by swapper/1/0: #0: ffffffff83576be0 (rcu_callback){....}-{0:0}, at: rcu_lock_acquire+0x7/0x30 stack backtrace: CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G E 6.13.0-rc5-build2+ #1223 Tainted: [E]=UNSIGNED_MODULE Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014 Call Trace: <IRQ> dump_stack_lvl+0x57/0x80 print_usage_bug.part.0+0x227/0x240 valid_state+0x53/0x70 mark_lock_irq+0xa5/0x2f0 mark_lock+0xf7/0x170 mark_usage+0xe1/0x180 __lock_acquire+0x544/0x990 lock_acquire.part.0+0x103/0x280 _raw_spin_lock+0x2f/0x40 rxrpc_put_peer+0xcb/0x180 afs_free_addrlist+0x46/0x90 [kafs] rcu_do_batch+0x2d2/0x640 rcu_core+0x2f7/0x350 handle_softirqs+0x1ee/0x430 __irq_exit_rcu+0x44/0x110 irq_exit_rcu+0xa/0x30 sysvec_apic_timer_interrupt+0x7f/0xa0 </IRQ>
References
Impacted products
Vendor Product Version
Linux Linux Version: 72904d7b9bfbf2dd146254edea93958bc35bbbfe
Version: 72904d7b9bfbf2dd146254edea93958bc35bbbfe
Version: 72904d7b9bfbf2dd146254edea93958bc35bbbfe
Version: 056fc740be000d39a7dba700a935f3bbfbc664e6
Version: 6.7.3   ≤
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              "userInteraction": "NONE",
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              "version": "3.1"
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              "content": {
                "id": "CVE-2025-21809",
                "options": [
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          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
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    "cna": {
      "affected": [
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          "product": "Linux",
          "programFiles": [
            "net/rxrpc/peer_event.c",
            "net/rxrpc/peer_object.c"
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          "versions": [
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              "status": "unaffected",
              "version": "6.12.13",
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                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nrxrpc, afs: Fix peer hash locking vs RCU callback\n\nIn its address list, afs now retains pointers to and refs on one or more\nrxrpc_peer objects.  The address list is freed under RCU and at this time,\nit puts the refs on those peers.\n\nNow, when an rxrpc_peer object runs out of refs, it gets removed from the\npeer hash table and, for that, rxrpc has to take a spinlock.  However, it\nis now being called from afs\u0027s RCU cleanup, which takes place in BH\ncontext - but it is just taking an ordinary spinlock.\n\nThe put may also be called from non-BH context, and so there exists the\npossibility of deadlock if the BH-based RCU cleanup happens whilst the hash\nspinlock is held.  This led to the attached lockdep complaint.\n\nFix this by changing spinlocks of rxnet-\u003epeer_hash_lock back to\nBH-disabling locks.\n\n    ================================\n    WARNING: inconsistent lock state\n    6.13.0-rc5-build2+ #1223 Tainted: G            E\n    --------------------------------\n    inconsistent {SOFTIRQ-ON-W} -\u003e {IN-SOFTIRQ-W} usage.\n    swapper/1/0 [HC0[0]:SC1[1]:HE1:SE0] takes:\n    ffff88810babe228 (\u0026rxnet-\u003epeer_hash_lock){+.?.}-{3:3}, at: rxrpc_put_peer+0xcb/0x180\n    {SOFTIRQ-ON-W} state was registered at:\n      mark_usage+0x164/0x180\n      __lock_acquire+0x544/0x990\n      lock_acquire.part.0+0x103/0x280\n      _raw_spin_lock+0x2f/0x40\n      rxrpc_peer_keepalive_worker+0x144/0x440\n      process_one_work+0x486/0x7c0\n      process_scheduled_works+0x73/0x90\n      worker_thread+0x1c8/0x2a0\n      kthread+0x19b/0x1b0\n      ret_from_fork+0x24/0x40\n      ret_from_fork_asm+0x1a/0x30\n    irq event stamp: 972402\n    hardirqs last  enabled at (972402): [\u003cffffffff8244360e\u003e] _raw_spin_unlock_irqrestore+0x2e/0x50\n    hardirqs last disabled at (972401): [\u003cffffffff82443328\u003e] _raw_spin_lock_irqsave+0x18/0x60\n    softirqs last  enabled at (972300): [\u003cffffffff810ffbbe\u003e] handle_softirqs+0x3ee/0x430\n    softirqs last disabled at (972313): [\u003cffffffff810ffc54\u003e] __irq_exit_rcu+0x44/0x110\n\n    other info that might help us debug this:\n     Possible unsafe locking scenario:\n           CPU0\n           ----\n      lock(\u0026rxnet-\u003epeer_hash_lock);\n      \u003cInterrupt\u003e\n        lock(\u0026rxnet-\u003epeer_hash_lock);\n\n     *** DEADLOCK ***\n    1 lock held by swapper/1/0:\n     #0: ffffffff83576be0 (rcu_callback){....}-{0:0}, at: rcu_lock_acquire+0x7/0x30\n\n    stack backtrace:\n    CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G            E      6.13.0-rc5-build2+ #1223\n    Tainted: [E]=UNSIGNED_MODULE\n    Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014\n    Call Trace:\n     \u003cIRQ\u003e\n     dump_stack_lvl+0x57/0x80\n     print_usage_bug.part.0+0x227/0x240\n     valid_state+0x53/0x70\n     mark_lock_irq+0xa5/0x2f0\n     mark_lock+0xf7/0x170\n     mark_usage+0xe1/0x180\n     __lock_acquire+0x544/0x990\n     lock_acquire.part.0+0x103/0x280\n     _raw_spin_lock+0x2f/0x40\n     rxrpc_put_peer+0xcb/0x180\n     afs_free_addrlist+0x46/0x90 [kafs]\n     rcu_do_batch+0x2d2/0x640\n     rcu_core+0x2f7/0x350\n     handle_softirqs+0x1ee/0x430\n     __irq_exit_rcu+0x44/0x110\n     irq_exit_rcu+0xa/0x30\n     sysvec_apic_timer_interrupt+0x7f/0xa0\n     \u003c/IRQ\u003e"
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
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            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - rxrpc is a UDP network protocol; the vulnerable `spin_lock(\u0026rxnet-\u003epeer_hash_lock)` in `rxrpc_new_incoming_peer()` is executed by the io_thread directly in response to packets received on the AFS callback-manager port (UDP 7001), and the softirq side is driven by address-list churn parsed from remote VL/fileserver responses. Both sides of the deadlock are reachable and rate-controllable from off-host network traffic.\nAC:L - The attacker controls both sides of the timing window \u2014 flooding spoofed-source rxrpc DATA packets forces unbounded process-context acquisitions of `peer_hash_lock` with softirqs enabled, while attacker-influenced address-list churn queues `afs_free_addrlist` RCU callbacks that take the same lock from `RCU_SOFTIRQ`. At attacker-chosen packet rates the softirq reliably lands on a CPU holding the lock.\nPR:N - `rxrpc_new_incoming_call()` builds the peer object and takes the hash lock before any rxrpc security challenge is issued (`RXRPC_CONN_SERVICE_UNSECURED` \u2192 `CHALLENGING` is set afterwards), so no credentials or prior authentication are needed to reach the lock acquisition.\nUI:N - No victim action is required; an AFS client with the kafs module in use processes the attacker\u0027s packets and its own RCU address-list frees automatically.\nS:U - The deadlock wedges the kernel that owns the vulnerable code; no security boundary such as a VM, IOMMU, or sandbox is crossed.\nC:N - The defect is a lock-context inversion with no out-of-bounds access, no use-after-free, and no leakage of kernel memory or pointers to the attacker.\nI:N - No memory is corrupted and no data is modified \u2014 the fix only converts `spin_lock()` to `spin_lock_bh()` on `peer_hash_lock`, with no change to any data manipulation.\nA:H - A softirq spinning on a lock held by the interrupted process context on the same CPU is an unrecoverable self-deadlock that permanently wedges that CPU while holding `peer_hash_lock`, cascading to every other CPU doing rxrpc packet input, `sendmsg`, or peer teardown, resulting in a hard lockup/system hang."
            }
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        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T11:54:36.772Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
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        {
          "url": "https://git.kernel.org/stable/c/10ba5a3d57af20e494e0d979d1894260989235dd"
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          "url": "https://git.kernel.org/stable/c/0e77dd41689637ac4e1b8fe0f27541f373640855"
        },
        {
          "url": "https://git.kernel.org/stable/c/79d458c13056559d49b5e41fbc4b6890e68cf65b"
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      ],
      "title": "rxrpc, afs: Fix peer hash locking vs RCU callback",
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  "cveMetadata": {
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    "assignerShortName": "Linux",
    "cveId": "CVE-2025-21809",
    "datePublished": "2025-02-27T20:01:00.969Z",
    "dateReserved": "2024-12-29T08:45:45.772Z",
    "dateUpdated": "2026-08-05T11:54:36.772Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 5.5, \"attackVector\": \"LOCAL\", \"baseSeverity\": \"MEDIUM\", \"vectorString\": \"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H\", \"integrityImpact\": \"NONE\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"HIGH\", \"privilegesRequired\": \"LOW\", \"confidentialityImpact\": \"NONE\"}}, {\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2025-21809\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2025-10-01T19:28:41.037357Z\"}}}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-667\", \"description\": \"CWE-667 Improper Locking\"}]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2025-10-01T16:56:48.437Z\"}}], \"cna\": {\"title\": \"rxrpc, afs: Fix peer hash locking vs RCU callback\", \"metrics\": [{\"cvssV3_1\": {\"version\": \"3.1\", \"baseScore\": 7.5, \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"AV:N - rxrpc is a UDP network protocol; the vulnerable `spin_lock(\u0026rxnet-\u003epeer_hash_lock)` in `rxrpc_new_incoming_peer()` is executed by the io_thread directly in response to packets received on the AFS callback-manager port (UDP 7001), and the softirq side is driven by address-list churn parsed from remote VL/fileserver responses. Both sides of the deadlock are reachable and rate-controllable from off-host network traffic.\\nAC:L - The attacker controls both sides of the timing window \\u2014 flooding spoofed-source rxrpc DATA packets forces unbounded process-context acquisitions of `peer_hash_lock` with softirqs enabled, while attacker-influenced address-list churn queues `afs_free_addrlist` RCU callbacks that take the same lock from `RCU_SOFTIRQ`. At attacker-chosen packet rates the softirq reliably lands on a CPU holding the lock.\\nPR:N - `rxrpc_new_incoming_call()` builds the peer object and takes the hash lock before any rxrpc security challenge is issued (`RXRPC_CONN_SERVICE_UNSECURED` \\u2192 `CHALLENGING` is set afterwards), so no credentials or prior authentication are needed to reach the lock acquisition.\\nUI:N - No victim action is required; an AFS client with the kafs module in use processes the attacker\u0027s packets and its own RCU address-list frees automatically.\\nS:U - The deadlock wedges the kernel that owns the vulnerable code; no security boundary such as a VM, IOMMU, or sandbox is crossed.\\nC:N - The defect is a lock-context inversion with no out-of-bounds access, no use-after-free, and no leakage of kernel memory or pointers to the attacker.\\nI:N - No memory is corrupted and no data is modified \\u2014 the fix only converts `spin_lock()` to `spin_lock_bh()` on `peer_hash_lock`, with no change to any data manipulation.\\nA:H - A softirq spinning on a lock held by the interrupted process context on the same CPU is an unrecoverable self-deadlock that permanently wedges that CPU while holding `peer_hash_lock`, cascading to every other CPU doing rxrpc packet input, `sendmsg`, or peer teardown, resulting in a hard lockup/system hang.\"}]}], \"affected\": [{\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"72904d7b9bfbf2dd146254edea93958bc35bbbfe\", \"lessThan\": \"10ba5a3d57af20e494e0d979d1894260989235dd\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"72904d7b9bfbf2dd146254edea93958bc35bbbfe\", \"lessThan\": \"0e77dd41689637ac4e1b8fe0f27541f373640855\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"72904d7b9bfbf2dd146254edea93958bc35bbbfe\", \"lessThan\": \"79d458c13056559d49b5e41fbc4b6890e68cf65b\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"056fc740be000d39a7dba700a935f3bbfbc664e6\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"6.7.3\", \"lessThan\": \"6.8\", \"versionType\": \"semver\"}], \"programFiles\": [\"net/rxrpc/peer_event.c\", \"net/rxrpc/peer_object.c\"], \"defaultStatus\": \"unaffected\"}, {\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"6.8\"}, {\"status\": \"unaffected\", \"version\": \"0\", \"lessThan\": \"6.8\", \"versionType\": \"semver\"}, {\"status\": \"unaffected\", \"version\": \"6.12.13\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.12.*\"}, {\"status\": \"unaffected\", \"version\": \"6.13.2\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.13.*\"}, {\"status\": \"unaffected\", \"version\": \"6.14\", \"versionType\": \"original_commit_for_fix\", \"lessThanOrEqual\": \"*\"}], \"programFiles\": [\"net/rxrpc/peer_event.c\", \"net/rxrpc/peer_object.c\"], \"defaultStatus\": \"affected\"}], \"references\": [{\"url\": \"https://git.kernel.org/stable/c/10ba5a3d57af20e494e0d979d1894260989235dd\"}, {\"url\": \"https://git.kernel.org/stable/c/0e77dd41689637ac4e1b8fe0f27541f373640855\"}, {\"url\": \"https://git.kernel.org/stable/c/79d458c13056559d49b5e41fbc4b6890e68cf65b\"}], \"x_generator\": {\"engine\": \"bippy-1.2.0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"In the Linux kernel, the following vulnerability has been resolved:\\n\\nrxrpc, afs: Fix peer hash locking vs RCU callback\\n\\nIn its address list, afs now retains pointers to and refs on one or more\\nrxrpc_peer objects.  The address list is freed under RCU and at this time,\\nit puts the refs on those peers.\\n\\nNow, when an rxrpc_peer object runs out of refs, it gets removed from the\\npeer hash table and, for that, rxrpc has to take a spinlock.  However, it\\nis now being called from afs\u0027s RCU cleanup, which takes place in BH\\ncontext - but it is just taking an ordinary spinlock.\\n\\nThe put may also be called from non-BH context, and so there exists the\\npossibility of deadlock if the BH-based RCU cleanup happens whilst the hash\\nspinlock is held.  This led to the attached lockdep complaint.\\n\\nFix this by changing spinlocks of rxnet-\u003epeer_hash_lock back to\\nBH-disabling locks.\\n\\n    ================================\\n    WARNING: inconsistent lock state\\n    6.13.0-rc5-build2+ #1223 Tainted: G            E\\n    --------------------------------\\n    inconsistent {SOFTIRQ-ON-W} -\u003e {IN-SOFTIRQ-W} usage.\\n    swapper/1/0 [HC0[0]:SC1[1]:HE1:SE0] takes:\\n    ffff88810babe228 (\u0026rxnet-\u003epeer_hash_lock){+.?.}-{3:3}, at: rxrpc_put_peer+0xcb/0x180\\n    {SOFTIRQ-ON-W} state was registered at:\\n      mark_usage+0x164/0x180\\n      __lock_acquire+0x544/0x990\\n      lock_acquire.part.0+0x103/0x280\\n      _raw_spin_lock+0x2f/0x40\\n      rxrpc_peer_keepalive_worker+0x144/0x440\\n      process_one_work+0x486/0x7c0\\n      process_scheduled_works+0x73/0x90\\n      worker_thread+0x1c8/0x2a0\\n      kthread+0x19b/0x1b0\\n      ret_from_fork+0x24/0x40\\n      ret_from_fork_asm+0x1a/0x30\\n    irq event stamp: 972402\\n    hardirqs last  enabled at (972402): [\u003cffffffff8244360e\u003e] _raw_spin_unlock_irqrestore+0x2e/0x50\\n    hardirqs last disabled at (972401): [\u003cffffffff82443328\u003e] _raw_spin_lock_irqsave+0x18/0x60\\n    softirqs last  enabled at (972300): [\u003cffffffff810ffbbe\u003e] handle_softirqs+0x3ee/0x430\\n    softirqs last disabled at (972313): [\u003cffffffff810ffc54\u003e] __irq_exit_rcu+0x44/0x110\\n\\n    other info that might help us debug this:\\n     Possible unsafe locking scenario:\\n           CPU0\\n           ----\\n      lock(\u0026rxnet-\u003epeer_hash_lock);\\n      \u003cInterrupt\u003e\\n        lock(\u0026rxnet-\u003epeer_hash_lock);\\n\\n     *** DEADLOCK ***\\n    1 lock held by swapper/1/0:\\n     #0: ffffffff83576be0 (rcu_callback){....}-{0:0}, at: rcu_lock_acquire+0x7/0x30\\n\\n    stack backtrace:\\n    CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G            E      6.13.0-rc5-build2+ #1223\\n    Tainted: [E]=UNSIGNED_MODULE\\n    Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014\\n    Call Trace:\\n     \u003cIRQ\u003e\\n     dump_stack_lvl+0x57/0x80\\n     print_usage_bug.part.0+0x227/0x240\\n     valid_state+0x53/0x70\\n     mark_lock_irq+0xa5/0x2f0\\n     mark_lock+0xf7/0x170\\n     mark_usage+0xe1/0x180\\n     __lock_acquire+0x544/0x990\\n     lock_acquire.part.0+0x103/0x280\\n     _raw_spin_lock+0x2f/0x40\\n     rxrpc_put_peer+0xcb/0x180\\n     afs_free_addrlist+0x46/0x90 [kafs]\\n     rcu_do_batch+0x2d2/0x640\\n     rcu_core+0x2f7/0x350\\n     handle_softirqs+0x1ee/0x430\\n     __irq_exit_rcu+0x44/0x110\\n     irq_exit_rcu+0xa/0x30\\n     sysvec_apic_timer_interrupt+0x7f/0xa0\\n     \u003c/IRQ\u003e\"}], \"cpeApplicability\": [{\"nodes\": [{\"negate\": false, \"cpeMatch\": [{\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.12.13\", \"versionStartIncluding\": \"6.8\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.13.2\", \"versionStartIncluding\": \"6.8\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.14\", \"versionStartIncluding\": \"6.8\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionStartIncluding\": \"6.7.3\"}], \"operator\": \"OR\"}]}], \"providerMetadata\": {\"orgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"shortName\": \"Linux\", \"dateUpdated\": \"2026-08-05T11:54:36.772Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2025-21809\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-08-05T11:54:36.772Z\", \"dateReserved\": \"2024-12-29T08:45:45.772Z\", \"assignerOrgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"datePublished\": \"2025-02-27T20:01:00.969Z\", \"assignerShortName\": \"Linux\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}


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