Vulnerability-Lookup

CVE-2026-64352 (GCVE-0-2026-64352)

Vulnerability from cvelistv5 – Published: 2026-07-25 08:50 – Updated: 2026-07-25 08:50

Title

bpf: Allow LPM map access from sleepable BPF programs

Summary

In the Linux kernel, the following vulnerability has been resolved: bpf: Allow LPM map access from sleepable BPF programs trie_lookup_elem() annotates its rcu_dereference_check() walks with only rcu_read_lock_bh_held(). Because rcu_dereference_check(p, c) resolves to "c || rcu_read_lock_held()", this passes for XDP/NAPI and classic RCU readers but fails for sleepable BPF programs, which enter via __bpf_prog_enter_sleepable() and hold only rcu_read_lock_trace(). trie_update_elem() and trie_delete_elem() have the same problem in a different form: they walk the trie with plain rcu_dereference(), which asserts rcu_read_lock_held() unconditionally. Both are reachable from sleepable BPF programs via the bpf_map_update_elem / bpf_map_delete_elem helpers, and from the syscall path under classic rcu_read_lock(). In the writer paths the trie is actually protected by trie->lock (an rqspinlock taken across the walk); we never relied on the RCU read-side lock to keep nodes alive there. A sleepable LSM hook that ends up touching an LPM trie therefore triggers lockdep on debug kernels: ============================= WARNING: suspicious RCU usage 7.1.0-... Tainted: G E ----------------------------- kernel/bpf/lpm_trie.c:249 suspicious rcu_dereference_check() usage! 1 lock held by net_tests/540: #0: (rcu_tasks_trace_srcu_struct){....}-{0:0}, at: __bpf_prog_enter_sleepable+0x26/0x280 Call Trace: dump_stack_lvl lockdep_rcu_suspicious trie_lookup_elem bpf_prog_..._enforce_security_socket_connect bpf_trampoline_... security_socket_connect __sys_connect do_syscall_64 This is lockdep-only -- no UAF, since Tasks Trace RCU does serialize against the trie's reclaim path -- but it spams the console once per distinct callsite on every debug kernel running a sleepable BPF LSM that touches an LPM trie, which is increasingly common. For the lookup path, switch the rcu_dereference_check() annotation from rcu_read_lock_bh_held() to bpf_rcu_lock_held(), which accepts all three contexts (classic, BH, Tasks Trace). Other map types already follow this convention. For trie_update_elem() and trie_delete_elem(), annotate the walks as rcu_dereference_protected(*p, 1) -- matching trie_free() in the same file -- since trie->lock is held across the walk. rqspinlock has no lockdep_map, so the predicate degenerates to '1' rather than lockdep_is_held(&trie->lock); the protection is real but not machine-verifiable. trie_get_next_key() also uses bare rcu_dereference() but is reachable only from the BPF syscall, which holds classic rcu_read_lock() before dispatching, so it is left untouched.

Severity

No CVSS data available.

Assigner

Linux

References

7 references

URL	Tags
https://git.kernel.org/stable/c/f0967d4f1ba4323a3…
https://git.kernel.org/stable/c/304ca50582f0c0473…
https://git.kernel.org/stable/c/ec662a8b2cde01e76…
https://git.kernel.org/stable/c/9bfdf4b81b0e56d47…
https://git.kernel.org/stable/c/57454944737f3ad9a…
https://git.kernel.org/stable/c/bd6ad9a6b30498d84…
https://git.kernel.org/stable/c/2f884d371fafea137…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 694cea395fded425008e93cd90cfdf7a451674af , < f0967d4f1ba4323a3cb7dc8fdba74dd3a8caaf04 (git) Affected: 694cea395fded425008e93cd90cfdf7a451674af , < 304ca50582f0c047370f85e13caec456f78c9fcc (git) Affected: 694cea395fded425008e93cd90cfdf7a451674af , < ec662a8b2cde01e76b37ccd4b992d0342299e69c (git) Affected: 694cea395fded425008e93cd90cfdf7a451674af , < 9bfdf4b81b0e56d47bc6c46c34a46638be716695 (git) Affected: 694cea395fded425008e93cd90cfdf7a451674af , < 57454944737f3ad9a8703aecbbb79713b513a94b (git) Affected: 694cea395fded425008e93cd90cfdf7a451674af , < bd6ad9a6b30498d845413e863fb95c6fab3babe3 (git) Affected: 694cea395fded425008e93cd90cfdf7a451674af , < 2f884d371fafea137afea504d49ee4a7c8d7985b (git)
Linux	Linux	Affected: 5.14 Unaffected: 0 , < 5.14 (semver) Unaffected: 5.15.212 , ≤ 5.15.* (semver) Unaffected: 6.1.178 , ≤ 6.1.* (semver) Unaffected: 6.6.145 , ≤ 6.6.* (semver) Unaffected: 6.12.97 , ≤ 6.12.* (semver) Unaffected: 6.18.40 , ≤ 6.18.* (semver) Unaffected: 7.1.4 , ≤ 7.1.* (semver) Unaffected: 7.2-rc1 , ≤ * (original_commit_for_fix)

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    "dateReserved": "2026-07-19T15:36:31.782Z",
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      "cve": "CVE-2026-64352",
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      "product_status:under_investigation": "1",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "bpf: Allow LPM map access from sleepable BPF programs",
      "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-64352.json",
      "version": "1"
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    "nvd": "{\"cve\":{\"id\":\"CVE-2026-64352\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-07-25T10:17:17.547\",\"lastModified\":\"2026-07-25T10:17:17.547\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nbpf: Allow LPM map access from sleepable BPF programs\\n\\ntrie_lookup_elem() annotates its rcu_dereference_check() walks with\\nonly rcu_read_lock_bh_held().  Because rcu_dereference_check(p, c)\\nresolves to \\\"c || rcu_read_lock_held()\\\", this passes for XDP/NAPI and\\nclassic RCU readers but fails for sleepable BPF programs, which enter\\nvia __bpf_prog_enter_sleepable() and hold only rcu_read_lock_trace().\\n\\ntrie_update_elem() and trie_delete_elem() have the same problem in a\\ndifferent form: they walk the trie with plain rcu_dereference(), which\\nasserts rcu_read_lock_held() unconditionally.  Both are reachable from\\nsleepable BPF programs via the bpf_map_update_elem / bpf_map_delete_elem\\nhelpers, and from the syscall path under classic rcu_read_lock().  In\\nthe writer paths the trie is actually protected by trie-\u003elock (an\\nrqspinlock taken across the walk); we never relied on the RCU read-side\\nlock to keep nodes alive there.\\n\\nA sleepable LSM hook that ends up touching an LPM trie therefore\\ntriggers lockdep on debug kernels:\\n\\n  =============================\\n  WARNING: suspicious RCU usage\\n  7.1.0-... Tainted: G            E\\n  -----------------------------\\n  kernel/bpf/lpm_trie.c:249 suspicious rcu_dereference_check() usage!\\n  1 lock held by net_tests/540:\\n   #0: (rcu_tasks_trace_srcu_struct){....}-{0:0},\\n       at: __bpf_prog_enter_sleepable+0x26/0x280\\n  Call Trace:\\n   dump_stack_lvl\\n   lockdep_rcu_suspicious\\n   trie_lookup_elem\\n   bpf_prog_..._enforce_security_socket_connect\\n   bpf_trampoline_...\\n   security_socket_connect\\n   __sys_connect\\n   do_syscall_64\\n\\nThis is lockdep-only -- no UAF, since Tasks Trace RCU does serialize\\nagainst the trie\u0027s reclaim path -- but it spams the console once per\\ndistinct callsite on every debug kernel running a sleepable BPF LSM\\nthat touches an LPM trie, which is increasingly common.\\n\\nFor the lookup path, switch the rcu_dereference_check() annotation\\nfrom rcu_read_lock_bh_held() to bpf_rcu_lock_held(), which accepts all\\nthree contexts (classic, BH, Tasks Trace).  Other map types already\\nfollow this convention.\\n\\nFor trie_update_elem() and trie_delete_elem(), annotate the walks as\\nrcu_dereference_protected(*p, 1) -- matching trie_free() in the same\\nfile -- since trie-\u003elock is held across the walk.  rqspinlock has no\\nlockdep_map, so the predicate degenerates to \u00271\u0027 rather than\\nlockdep_is_held(\u0026trie-\u003elock); the protection is real but not\\nmachine-verifiable.  trie_get_next_key() also uses bare\\nrcu_dereference() but is reachable only from the BPF syscall, which\\nholds classic rcu_read_lock() before dispatching, so it is left\\nuntouched.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"kernel/bpf/lpm_trie.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"694cea395fded425008e93cd90cfdf7a451674af\",\"lessThan\":\"f0967d4f1ba4323a3cb7dc8fdba74dd3a8caaf04\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"694cea395fded425008e93cd90cfdf7a451674af\",\"lessThan\":\"304ca50582f0c047370f85e13caec456f78c9fcc\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"694cea395fded425008e93cd90cfdf7a451674af\",\"lessThan\":\"ec662a8b2cde01e76b37ccd4b992d0342299e69c\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"694cea395fded425008e93cd90cfdf7a451674af\",\"lessThan\":\"9bfdf4b81b0e56d47bc6c46c34a46638be716695\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"694cea395fded425008e93cd90cfdf7a451674af\",\"lessThan\":\"57454944737f3ad9a8703aecbbb79713b513a94b\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"694cea395fded425008e93cd90cfdf7a451674af\",\"lessThan\":\"bd6ad9a6b30498d845413e863fb95c6fab3babe3\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"694cea395fded425008e93cd90cfdf7a451674af\",\"lessThan\":\"2f884d371fafea137afea504d49ee4a7c8d7985b\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"kernel/bpf/lpm_trie.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"5.14\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"5.14\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.15.212\",\"lessThanOrEqual\":\"5.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.178\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.145\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.97\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.40\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.1.4\",\"lessThanOrEqual\":\"7.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.2-rc1\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/2f884d371fafea137afea504d49ee4a7c8d7985b\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/304ca50582f0c047370f85e13caec456f78c9fcc\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/57454944737f3ad9a8703aecbbb79713b513a94b\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/9bfdf4b81b0e56d47bc6c46c34a46638be716695\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/bd6ad9a6b30498d845413e863fb95c6fab3babe3\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/ec662a8b2cde01e76b37ccd4b992d0342299e69c\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/f0967d4f1ba4323a3cb7dc8fdba74dd3a8caaf04\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "suse_vex": {
      "aggregate_severity": "not set",
      "current_release_date": "2026-07-25T16:01:11Z",
      "cve": "CVE-2026-64352",
      "id": "CVE-2026-64352",
      "initial_release_date": "2026-07-25T16:01:11Z",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-64352",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-64352.json",
      "version": "2"
    }
  }
}

GHSA-P2WC-GRC5-CWHM

Vulnerability from github – Published: 2026-07-25 12:31 – Updated: 2026-07-25 12:31

Details

In the Linux kernel, the following vulnerability has been resolved:

bpf: Allow LPM map access from sleepable BPF programs

trie_lookup_elem() annotates its rcu_dereference_check() walks with only rcu_read_lock_bh_held(). Because rcu_dereference_check(p, c) resolves to "c || rcu_read_lock_held()", this passes for XDP/NAPI and classic RCU readers but fails for sleepable BPF programs, which enter via __bpf_prog_enter_sleepable() and hold only rcu_read_lock_trace().

trie_update_elem() and trie_delete_elem() have the same problem in a different form: they walk the trie with plain rcu_dereference(), which asserts rcu_read_lock_held() unconditionally. Both are reachable from sleepable BPF programs via the bpf_map_update_elem / bpf_map_delete_elem helpers, and from the syscall path under classic rcu_read_lock(). In the writer paths the trie is actually protected by trie->lock (an rqspinlock taken across the walk); we never relied on the RCU read-side lock to keep nodes alive there.

A sleepable LSM hook that ends up touching an LPM trie therefore triggers lockdep on debug kernels:

============================= WARNING: suspicious RCU usage 7.1.0-... Tainted: G E

kernel/bpf/lpm_trie.c:249 suspicious rcu_dereference_check() usage! 1 lock held by net_tests/540: #0: (rcu_tasks_trace_srcu_struct){....}-{0:0}, at: __bpf_prog_enter_sleepable+0x26/0x280 Call Trace: dump_stack_lvl lockdep_rcu_suspicious trie_lookup_elem bpf_prog_...enforce_security_socket_connect bpf_trampoline... security_socket_connect __sys_connect do_syscall_64

This is lockdep-only -- no UAF, since Tasks Trace RCU does serialize against the trie's reclaim path -- but it spams the console once per distinct callsite on every debug kernel running a sleepable BPF LSM that touches an LPM trie, which is increasingly common.

For the lookup path, switch the rcu_dereference_check() annotation from rcu_read_lock_bh_held() to bpf_rcu_lock_held(), which accepts all three contexts (classic, BH, Tasks Trace). Other map types already follow this convention.

For trie_update_elem() and trie_delete_elem(), annotate the walks as rcu_dereference_protected(*p, 1) -- matching trie_free() in the same file -- since trie->lock is held across the walk. rqspinlock has no lockdep_map, so the predicate degenerates to '1' rather than lockdep_is_held(&trie->lock); the protection is real but not machine-verifiable. trie_get_next_key() also uses bare rcu_dereference() but is reachable only from the BPF syscall, which holds classic rcu_read_lock() before dispatching, so it is left untouched.

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{
  "affected": [],
  "aliases": [
    "CVE-2026-64352"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-25T10:17:17Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Allow LPM map access from sleepable BPF programs\n\ntrie_lookup_elem() annotates its rcu_dereference_check() walks with\nonly rcu_read_lock_bh_held().  Because rcu_dereference_check(p, c)\nresolves to \"c || rcu_read_lock_held()\", this passes for XDP/NAPI and\nclassic RCU readers but fails for sleepable BPF programs, which enter\nvia __bpf_prog_enter_sleepable() and hold only rcu_read_lock_trace().\n\ntrie_update_elem() and trie_delete_elem() have the same problem in a\ndifferent form: they walk the trie with plain rcu_dereference(), which\nasserts rcu_read_lock_held() unconditionally.  Both are reachable from\nsleepable BPF programs via the bpf_map_update_elem / bpf_map_delete_elem\nhelpers, and from the syscall path under classic rcu_read_lock().  In\nthe writer paths the trie is actually protected by trie-\u003elock (an\nrqspinlock taken across the walk); we never relied on the RCU read-side\nlock to keep nodes alive there.\n\nA sleepable LSM hook that ends up touching an LPM trie therefore\ntriggers lockdep on debug kernels:\n\n  =============================\n  WARNING: suspicious RCU usage\n  7.1.0-... Tainted: G            E\n  -----------------------------\n  kernel/bpf/lpm_trie.c:249 suspicious rcu_dereference_check() usage!\n  1 lock held by net_tests/540:\n   #0: (rcu_tasks_trace_srcu_struct){....}-{0:0},\n       at: __bpf_prog_enter_sleepable+0x26/0x280\n  Call Trace:\n   dump_stack_lvl\n   lockdep_rcu_suspicious\n   trie_lookup_elem\n   bpf_prog_..._enforce_security_socket_connect\n   bpf_trampoline_...\n   security_socket_connect\n   __sys_connect\n   do_syscall_64\n\nThis is lockdep-only -- no UAF, since Tasks Trace RCU does serialize\nagainst the trie\u0027s reclaim path -- but it spams the console once per\ndistinct callsite on every debug kernel running a sleepable BPF LSM\nthat touches an LPM trie, which is increasingly common.\n\nFor the lookup path, switch the rcu_dereference_check() annotation\nfrom rcu_read_lock_bh_held() to bpf_rcu_lock_held(), which accepts all\nthree contexts (classic, BH, Tasks Trace).  Other map types already\nfollow this convention.\n\nFor trie_update_elem() and trie_delete_elem(), annotate the walks as\nrcu_dereference_protected(*p, 1) -- matching trie_free() in the same\nfile -- since trie-\u003elock is held across the walk.  rqspinlock has no\nlockdep_map, so the predicate degenerates to \u00271\u0027 rather than\nlockdep_is_held(\u0026trie-\u003elock); the protection is real but not\nmachine-verifiable.  trie_get_next_key() also uses bare\nrcu_dereference() but is reachable only from the BPF syscall, which\nholds classic rcu_read_lock() before dispatching, so it is left\nuntouched.",
  "id": "GHSA-p2wc-grc5-cwhm",
  "modified": "2026-07-25T12:31:32Z",
  "published": "2026-07-25T12:31:32Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64352"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2f884d371fafea137afea504d49ee4a7c8d7985b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/304ca50582f0c047370f85e13caec456f78c9fcc"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/57454944737f3ad9a8703aecbbb79713b513a94b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9bfdf4b81b0e56d47bc6c46c34a46638be716695"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/bd6ad9a6b30498d845413e863fb95c6fab3babe3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ec662a8b2cde01e76b37ccd4b992d0342299e69c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f0967d4f1ba4323a3cb7dc8fdba74dd3a8caaf04"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

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Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.

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CVE-2026-64352 (GCVE-0-2026-64352)

GHSA-P2WC-GRC5-CWHM

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