{
  "cveId": "CVE-2023-52446",
  "url": "https://patchblox.com/security/cve/CVE-2023-52446",
  "summary": "CVE-2023-52446 is fixed in linux on 1 platform, first by DEBIAN-CVE-2023-52446, released February 22, 2024. It is not reported as exploited. Patch Radar priority: High.",
  "title": "linux: In the Linux kernel, the following vulnerability has been resolved:  bpf: Fix a race condition between btf_put() and...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  bpf: Fix a race condition between btf_put() and map_free()  When running \u0060./test_progs -j\u0060 in my local vm with latest kernel, I once hit a kasan error like below:    [ 1887.184724] BUG: KASAN: slab-use-after-free in bpf_rb_root_free\u002B0x1f8/0x2b0   [ 1887.185599] Read of size 4 at addr ffff888106806910 by task kworker/u12:2/2830   [ 1887.186498]   [ 1887.186712] CPU: 3 PID: 2830 Comm: kworker/u12:2 Tainted: G           OEL     6.7.0-rc3-00699-g90679706d486-dirty #494   [ 1887.188034] Hardware name: QEMU Standard PC (i440FX \u002B PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014   [ 1887.189618] Workqueue: events_unbound bpf_map_free_deferred   [ 1887.190341] Call Trace:   [ 1887.190666]  \u003CTASK\u003E   [ 1887.190949]  dump_stack_lvl\u002B0xac/0xe0   [ 1887.191423]  ? nf_tcp_handle_invalid\u002B0x1b0/0x1b0   [ 1887.192019]  ? panic\u002B0x3c0/0x3c0   [ 1887.192449]  print_report\u002B0x14f/0x720   [ 1887.192930]  ? preempt_count_sub\u002B0x1c/0xd0   [ 1887.193459]  ? __virt_addr_valid\u002B0xac/0x120   [ 1887.194004]  ? bpf_rb_root_free\u002B0x1f8/0x2b0   [ 1887.194572]  kasan_report\u002B0xc3/0x100   [ 1887.195085]  ? bpf_rb_root_free\u002B0x1f8/0x2b0   [ 1887.195668]  bpf_rb_root_free\u002B0x1f8/0x2b0   [ 1887.196183]  ? __bpf_obj_drop_impl\u002B0xb0/0xb0   [ 1887.196736]  ? preempt_count_sub\u002B0x1c/0xd0   [ 1887.197270]  ? preempt_count_sub\u002B0x1c/0xd0   [ 1887.197802]  ? _raw_spin_unlock\u002B0x1f/0x40   [ 1887.198319]  bpf_obj_free_fields\u002B0x1d4/0x260   [ 1887.198883]  array_map_free\u002B0x1a3/0x260   [ 1887.199380]  bpf_map_free_deferred\u002B0x7b/0xe0   [ 1887.199943]  process_scheduled_works\u002B0x3a2/0x6c0   [ 1887.200549]  worker_thread\u002B0x633/0x890   [ 1887.201047]  ? __kthread_parkme\u002B0xd7/0xf0   [ 1887.201574]  ? kthread\u002B0x102/0x1d0   [ 1887.202020]  kthread\u002B0x1ab/0x1d0   [ 1887.202447]  ? pr_cont_work\u002B0x270/0x270   [ 1887.202954]  ? kthread_blkcg\u002B0x50/0x50   [ 1887.203444]  ret_from_fork\u002B0x34/0x50   [ 1887.203914]  ? kthread_blkcg\u002B0x50/0x50   [ 1887.204397]  ret_from_fork_asm\u002B0x11/0x20   [ 1887.204913]  \u003C/TASK\u003E   [ 1887.204913]  \u003C/TASK\u003E   [ 1887.205209]   [ 1887.205416] Allocated by task 2197:   [ 1887.205881]  kasan_set_track\u002B0x3f/0x60   [ 1887.206366]  __kasan_kmalloc\u002B0x6e/0x80   [ 1887.206856]  __kmalloc\u002B0xac/0x1a0   [ 1887.207293]  btf_parse_fields\u002B0xa15/0x1480   [ 1887.207836]  btf_parse_struct_metas\u002B0x566/0x670   [ 1887.208387]  btf_new_fd\u002B0x294/0x4d0   [ 1887.208851]  __sys_bpf\u002B0x4ba/0x600   [ 1887.209292]  __x64_sys_bpf\u002B0x41/0x50   [ 1887.209762]  do_syscall_64\u002B0x4c/0xf0   [ 1887.210222]  entry_SYSCALL_64_after_hwframe\u002B0x63/0x6b   [ 1887.210868]   [ 1887.211074] Freed by task 36:   [ 1887.211460]  kasan_set_track\u002B0x3f/0x60   [ 1887.211951]  kasan_save_free_info\u002B0x28/0x40   [ 1887.212485]  ____kasan_slab_free\u002B0x101/0x180   [ 1887.213027]  __kmem_cache_free\u002B0xe4/0x210   [ 1887.213514]  btf_free\u002B0x5b/0x130   [ 1887.213918]  rcu_core\u002B0x638/0xcc0   [ 1887.214347]  __do_softirq\u002B0x114/0x37e  The error happens at bpf_rb_root_free\u002B0x1f8/0x2b0:    00000000000034c0 \u003Cbpf_rb_root_free\u003E:   ; {     34c0: f3 0f 1e fa                   endbr64     34c4: e8 00 00 00 00                callq   0x34c9 \u003Cbpf_rb_root_free\u002B0x9\u003E     34c9: 55                            pushq   %rbp     34ca: 48 89 e5                      movq    %rsp, %rbp   ...   ;       if (rec \u0026\u0026 rec-\u003Erefcount_off \u003E= 0 \u0026\u0026     36aa: 4d 85 ed                      testq   %r13, %r13     36ad: 74 a9                         je      0x3658 \u003Cbpf_rb_root_free\u002B0x198\u003E     36af: 49 8d 7d 10                   leaq    0x10(%r13), %rdi     36b3: e8 00 00 00 00                callq   0x36b8 \u003Cbpf_rb_root_free\u002B0x1f8\u003E                                         \u003C==== kasan function     36b8: 45 8b 7d 10                   movl    0x10(%r13), %r15d                                         \u003C==== use-after-free load     36bc: 45 85 ff                      testl   %r15d, %r15d     36bf: 78 8c                         js      0x364d \u003Cbpf_rb_root_free\u002B0x18d\u003E  So the problem  ---truncated---",
  "published": "2024-02-22T17:15:08Z",
  "severity": "high",
  "cvss": 7.8,
  "cvssVector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
  "epss": 0.00226,
  "epssPercentile": 0.13431,
  "priority": "High",
  "priorityTier": 3,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "6.6.15-1",
      "fix": "DEBIAN-CVE-2023-52446",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2023-52446",
      "released": "2024-02-22T17:15:08Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "6.6.15-1",
      "fix": "DEBIAN-CVE-2023-52446",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2023-52446",
      "released": "2024-02-22T17:15:08Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-09T01:18:40Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}