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CVE-2025-22030 (GCVE-0-2025-22030)

Vulnerability from cvelistv5 – Published: 2025-04-16 14:11 – Updated: 2026-05-23 15:57
VLAI
Title
mm: zswap: fix crypto_free_acomp() deadlock in zswap_cpu_comp_dead()
Summary
In the Linux kernel, the following vulnerability has been resolved: mm: zswap: fix crypto_free_acomp() deadlock in zswap_cpu_comp_dead() Currently, zswap_cpu_comp_dead() calls crypto_free_acomp() while holding the per-CPU acomp_ctx mutex. crypto_free_acomp() then holds scomp_lock (through crypto_exit_scomp_ops_async()). On the other hand, crypto_alloc_acomp_node() holds the scomp_lock (through crypto_scomp_init_tfm()), and then allocates memory. If the allocation results in reclaim, we may attempt to hold the per-CPU acomp_ctx mutex. The above dependencies can cause an ABBA deadlock. For example in the following scenario: (1) Task A running on CPU #1: crypto_alloc_acomp_node() Holds scomp_lock Enters reclaim Reads per_cpu_ptr(pool->acomp_ctx, 1) (2) Task A is descheduled (3) CPU #1 goes offline zswap_cpu_comp_dead(CPU #1) Holds per_cpu_ptr(pool->acomp_ctx, 1)) Calls crypto_free_acomp() Waits for scomp_lock (4) Task A running on CPU #2: Waits for per_cpu_ptr(pool->acomp_ctx, 1) // Read on CPU #1 DEADLOCK Since there is no requirement to call crypto_free_acomp() with the per-CPU acomp_ctx mutex held in zswap_cpu_comp_dead(), move it after the mutex is unlocked. Also move the acomp_request_free() and kfree() calls for consistency and to avoid any potential sublte locking dependencies in the future. With this, only setting acomp_ctx fields to NULL occurs with the mutex held. This is similar to how zswap_cpu_comp_prepare() only initializes acomp_ctx fields with the mutex held, after performing all allocations before holding the mutex. Opportunistically, move the NULL check on acomp_ctx so that it takes place before the mutex dereference.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 8d29ff5d50304daa41dc3cfdda4a9d1e46cf5be1 , < 747e3eec1d7d124ea90ed3d7b85369df8b4e36d2 (git)
Affected: 12dcb0ef540629a281533f9dedc1b6b8e14cfb65 , < a8d18000e9d2d97aaf105f5f9b3b0e8a6fbf8b96 (git)
Affected: 12dcb0ef540629a281533f9dedc1b6b8e14cfb65 , < 717d9c35deff6c33235693171bacbb03e9643fa4 (git)
Affected: 12dcb0ef540629a281533f9dedc1b6b8e14cfb65 , < c11bcbc0a517acf69282c8225059b2a8ac5fe628 (git)
Affected: 6.12.12 , < 6.12.23 (semver)
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Linux Linux Affected: 6.13
Unaffected: 0 , < 6.13 (semver)
Unaffected: 6.12.23 , ≤ 6.12.* (semver)
Unaffected: 6.13.11 , ≤ 6.13.* (semver)
Unaffected: 6.14.2 , ≤ 6.14.* (semver)
Unaffected: 6.15 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm: zswap: fix crypto_free_acomp() deadlock in zswap_cpu_comp_dead()\n\nCurrently, zswap_cpu_comp_dead() calls crypto_free_acomp() while holding\nthe per-CPU acomp_ctx mutex.  crypto_free_acomp() then holds scomp_lock\n(through crypto_exit_scomp_ops_async()).\n\nOn the other hand, crypto_alloc_acomp_node() holds the scomp_lock (through\ncrypto_scomp_init_tfm()), and then allocates memory.  If the allocation\nresults in reclaim, we may attempt to hold the per-CPU acomp_ctx mutex.\n\nThe above dependencies can cause an ABBA deadlock.  For example in the\nfollowing scenario:\n\n(1) Task A running on CPU #1:\n    crypto_alloc_acomp_node()\n      Holds scomp_lock\n      Enters reclaim\n      Reads per_cpu_ptr(pool-\u003eacomp_ctx, 1)\n\n(2) Task A is descheduled\n\n(3) CPU #1 goes offline\n    zswap_cpu_comp_dead(CPU #1)\n      Holds per_cpu_ptr(pool-\u003eacomp_ctx, 1))\n      Calls crypto_free_acomp()\n      Waits for scomp_lock\n\n(4) Task A running on CPU #2:\n      Waits for per_cpu_ptr(pool-\u003eacomp_ctx, 1) // Read on CPU #1\n      DEADLOCK\n\nSince there is no requirement to call crypto_free_acomp() with the per-CPU\nacomp_ctx mutex held in zswap_cpu_comp_dead(), move it after the mutex is\nunlocked.  Also move the acomp_request_free() and kfree() calls for\nconsistency and to avoid any potential sublte locking dependencies in the\nfuture.\n\nWith this, only setting acomp_ctx fields to NULL occurs with the mutex\nheld.  This is similar to how zswap_cpu_comp_prepare() only initializes\nacomp_ctx fields with the mutex held, after performing all allocations\nbefore holding the mutex.\n\nOpportunistically, move the NULL check on acomp_ctx so that it takes place\nbefore the mutex dereference."
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        "dateUpdated": "2026-05-23T15:57:40.079Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
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For example in the\\nfollowing scenario:\\n\\n(1) Task A running on CPU #1:\\n    crypto_alloc_acomp_node()\\n      Holds scomp_lock\\n      Enters reclaim\\n      Reads per_cpu_ptr(pool-\u003eacomp_ctx, 1)\\n\\n(2) Task A is descheduled\\n\\n(3) CPU #1 goes offline\\n    zswap_cpu_comp_dead(CPU #1)\\n      Holds per_cpu_ptr(pool-\u003eacomp_ctx, 1))\\n      Calls crypto_free_acomp()\\n      Waits for scomp_lock\\n\\n(4) Task A running on CPU #2:\\n      Waits for per_cpu_ptr(pool-\u003eacomp_ctx, 1) // Read on CPU #1\\n      DEADLOCK\\n\\nSince there is no requirement to call crypto_free_acomp() with the per-CPU\\nacomp_ctx mutex held in zswap_cpu_comp_dead(), move it after the mutex is\\nunlocked.  Also move the acomp_request_free() and kfree() calls for\\nconsistency and to avoid any potential sublte locking dependencies in the\\nfuture.\\n\\nWith this, only setting acomp_ctx fields to NULL occurs with the mutex\\nheld.  This is similar to how zswap_cpu_comp_prepare() only initializes\\nacomp_ctx fields with the mutex held, after performing all allocations\\nbefore holding the mutex.\\n\\nOpportunistically, move the NULL check on acomp_ctx so that it takes place\\nbefore the mutex dereference.\"},{\"lang\":\"es\",\"value\":\"En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: mm: zswap: correcci\u00f3n del bloqueo de crypto_free_acomp() en zswap_cpu_comp_dead(). Actualmente, zswap_cpu_comp_dead() llama a crypto_free_acomp() mientras mantiene el mutex acomp_ctx por CPU. A continuaci\u00f3n, crypto_free_acomp() mantiene scomp_lock (mediante crypto_exit_scomp_ops_async()). Por otro lado, crypto_alloc_acomp_node() mantiene scomp_lock (mediante crypto_scomp_init_tfm()) y luego asigna memoria. Si la asignaci\u00f3n resulta en una recuperaci\u00f3n, podemos intentar mantener el mutex acomp_ctx por CPU. Las dependencias anteriores pueden causar un bloqueo de ABBA. 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    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-06-30T00:44:15+00:00",
      "cve": "CVE-2025-22030",
      "id": "CVE-2025-22030",
      "initial_release_date": "2025-04-16T00:00:00+00:00",
      "product_status:known_affected": "28",
      "product_status:known_not_affected": "246",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: mm: zswap: fix crypto_free_acomp() deadlock in zswap_cpu_comp_dead()",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-22030.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-09-07T16:36:38Z",
      "cve": "CVE-2025-22030",
      "id": "CVE-2025-22030",
      "initial_release_date": "2025-04-18T01:24:00Z",
      "product_status:known_affected": "565",
      "product_status:known_not_affected": "256",
      "product_status:recommended": "400",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2025-22030",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2025-22030.json",
      "version": "39"
    }
  }
}



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