CVE-2026-99204

{
  "id": "CVE-2026-99204",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-10-28T11:17:41.633",
  "lastModified": "2026-10-28T11:17:41.633",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nocfs2/dlm: Protect the recovery list during debugfs reads\n\nRecovery participant records must remain alive while debug_state_print()\nwalks reco.node_data and formats their fields. The formatter holds\ndlm->spinlock, but the recovery participant list is protected by\ndlm_reco_state_lock. In particular, dlm_destroy_recovery_area() detaches\nthe list under dlm_reco_state_lock and frees the detached records after\nreleasing it. A concurrent debugfs open can therefore read freed memory.\n\nProtect the participant traversal and field reads in debug_state_print()\nwith dlm_reco_state_lock, matching the existing list writers. This also\nserializes the traversal against list_add_tail() during recovery-area\ninitialization. Make the existing lock available to the debug code\nthrough dlmcommon.h; the lock remains internal to the OCFS2 DLM module.\n\nRelease dlm->spinlock after formatting the other domain state and before\nacquiring dlm_reco_state_lock, so the debug reader does not nest the two\nlocks. Leave recovery list insertion, detachment and freeing unchanged.\n\nKASAN report as below:\n\n    BUG: KASAN: slab-use-after-free in debug_state_open+0x1169/0x12d0\n    Read of size 4 at addr ffff88810662ef80 by task dlm-state-stres/896\n\n    CPU: 1 UID: 0 PID: 896 Comm: dlm-state-stres Not tainted 7.3.0-rc4-next-20260921-pmb-ocfs2-functional-v1+ #1 PREEMPT(lazy)\n    Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\n    Call Trace:\n     <TASK>\n     dump_stack_lvl+0x93/0xd0\n     print_report+0xce/0x630\n     ? debug_state_open+0x1169/0x12d0\n     ? srso_alias_return_thunk+0x5/0xfbef5\n     ? __virt_addr_valid+0x20e/0x420\n     ? debug_state_open+0x1169/0x12d0\n     kasan_report+0xe0/0x110\n     ? debug_state_open+0x1169/0x12d0\n     debug_state_open+0x1169/0x12d0\n     ? __pfx_debug_state_open+0x10/0x10\n     full_proxy_open_regular+0x193/0x310\n     do_dentry_open+0x595/0x12d0\n     ? __pfx_full_proxy_open_regular+0x10/0x10\n     vfs_open_consume+0xd1/0x400\n     ? srso_alias_return_thunk+0x5/0xfbef5\n     path_openat+0x18d0/0x2020\n     ? __pfx_path_openat+0x10/0x10\n     do_file_open+0x21e/0x470\n     ? __pfx_do_file_open+0x10/0x10\n     ? _raw_spin_unlock+0x23/0x40\n     ? srso_alias_return_thunk+0x5/0xfbef5\n     ? alloc_fd+0x3a6/0x6b0\n     do_sys_openat2+0xf4/0x1b0\n     ? __pfx_do_sys_openat2+0x10/0x10\n     ? srso_alias_return_thunk+0x5/0xfbef5\n     ? __fput+0x5b5/0xa60\n     __x64_sys_openat+0x136/0x1e0\n     ? __pfx___x64_sys_openat+0x10/0x10\n     do_syscall_64+0x114/0x620\n     entry_SYSCALL_64_after_hwframe+0x77/0x7f\n    [Register dump omitted.]\n     </TASK>\n\n    Allocated by task 880:\n     kasan_save_stack+0x33/0x60\n     kasan_save_track+0x14/0x30\n     __kasan_kmalloc+0xaa/0xb0\n     __kmalloc_cache_noprof+0x28d/0x610\n     dlm_remaster_locks+0x147/0x1d90\n     dlm_do_recovery+0xde1/0x1580\n     dlm_recovery_thread+0x109/0x300\n     kthread+0x351/0x460\n     ret_from_fork+0x659/0x940\n     ret_from_fork_asm+0x1a/0x30\n\n    Freed by task 880:\n     kasan_save_stack+0x33/0x60\n     kasan_save_track+0x14/0x30\n     kasan_save_free_info+0x3b/0x60\n     __kasan_slab_free+0x5f/0x80\n     kfree+0x308/0x580\n     dlm_destroy_recovery_area+0x285/0x460\n     dlm_remaster_locks+0x17c4/0x1d90\n     dlm_do_recovery+0xde1/0x1580\n     dlm_recovery_thread+0x109/0x300\n     kthread+0x351/0x460\n     ret_from_fork+0x659/0x940\n     ret_from_fork_asm+0x1a/0x30\n\n    The buggy address belongs to the object at ffff88810662ef80\n     which belongs to the cache kmalloc-32 of size 32\n    The buggy address is located 0 bytes inside of\n     freed 32-byte region [ffff88810662ef80, ffff88810662efa0)\n\n    [Page and memory-state dumps omitted.]"
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "fs/ocfs2/dlm/dlmcommon.h",
            "fs/ocfs2/dlm/dlmdebug.c",
            "fs/ocfs2/dlm/dlmrecovery.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "007dce53a29ccffc000ab5373d188f73881390fd",
              "lessThan": "04d4571c00db61a9664f387752fa05cb3c08a537",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "007dce53a29ccffc000ab5373d188f73881390fd",
              "lessThan": "2bc426a32bfb78868c7f76d9547132837b6b5284",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "007dce53a29ccffc000ab5373d188f73881390fd",
              "lessThan": "4c435828932bf46f29860e4a0375bcae101b778a",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "fs/ocfs2/dlm/dlmcommon.h",
            "fs/ocfs2/dlm/dlmdebug.c",
            "fs/ocfs2/dlm/dlmrecovery.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "2.6.26",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "2.6.26",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.59",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.13",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/04d4571c00db61a9664f387752fa05cb3c08a537",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/2bc426a32bfb78868c7f76d9547132837b6b5284",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/4c435828932bf46f29860e4a0375bcae101b778a",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}