CVE-2026-23036

{
  "id": "CVE-2026-23036",
  "cveTags": [],
  "metrics": {},
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "69673992b1aea5540199d9b8b658ede72f55a6cf",
              "lessThan": "65241e3ddda60b53a4ee3ae12721fc9ee21d5827",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "69673992b1aea5540199d9b8b658ede72f55a6cf",
              "lessThan": "1e1f2055ad5a7a5d548789b334a4473a7665c418",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "fs/btrfs/inode.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.13"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "6.13",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "6.18.7",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "status": "unaffected",
              "version": "6.19",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "fs/btrfs/inode.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-01-31T12:16:06.910",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/1e1f2055ad5a7a5d548789b334a4473a7665c418",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/65241e3ddda60b53a4ee3ae12721fc9ee21d5827",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Deferred",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: release path before iget_failed() in btrfs_read_locked_inode()\n\nIn btrfs_read_locked_inode() if we fail to lookup the inode, we jump to\nthe 'out' label with a path that has a read locked leaf and then we call\niget_failed(). This can result in a ABBA deadlock, since iget_failed()\ntriggers inode eviction and that causes the release of the delayed inode,\nwhich must lock the delayed inode's mutex, and a task updating a delayed\ninode starts by taking the node's mutex and then modifying the inode's\nsubvolume btree.\n\nSyzbot reported the following lockdep splat for this:\n\n   ======================================================\n   WARNING: possible circular locking dependency detected\n   syzkaller #0 Not tainted\n   ------------------------------------------------------\n   btrfs-cleaner/8725 is trying to acquire lock:\n   ffff0000d6826a48 (&delayed_node->mutex){+.+.}-{4:4}, at: __btrfs_release_delayed_node+0xa0/0x9b0 fs/btrfs/delayed-inode.c:290\n\n   but task is already holding lock:\n   ffff0000dbeba878 (btrfs-tree-00){++++}-{4:4}, at: btrfs_tree_read_lock_nested+0x44/0x2ec fs/btrfs/locking.c:145\n\n   which lock already depends on the new lock.\n\n   the existing dependency chain (in reverse order) is:\n\n   -> #1 (btrfs-tree-00){++++}-{4:4}:\n          __lock_release kernel/locking/lockdep.c:5574 [inline]\n          lock_release+0x198/0x39c kernel/locking/lockdep.c:5889\n          up_read+0x24/0x3c kernel/locking/rwsem.c:1632\n          btrfs_tree_read_unlock+0xdc/0x298 fs/btrfs/locking.c:169\n          btrfs_tree_unlock_rw fs/btrfs/locking.h:218 [inline]\n          btrfs_search_slot+0xa6c/0x223c fs/btrfs/ctree.c:2133\n          btrfs_lookup_inode+0xd8/0x38c fs/btrfs/inode-item.c:395\n          __btrfs_update_delayed_inode+0x124/0xed0 fs/btrfs/delayed-inode.c:1032\n          btrfs_update_delayed_inode fs/btrfs/delayed-inode.c:1118 [inline]\n          __btrfs_commit_inode_delayed_items+0x15f8/0x1748 fs/btrfs/delayed-inode.c:1141\n          __btrfs_run_delayed_items+0x1ac/0x514 fs/btrfs/delayed-inode.c:1176\n          btrfs_run_delayed_items_nr+0x28/0x38 fs/btrfs/delayed-inode.c:1219\n          flush_space+0x26c/0xb68 fs/btrfs/space-info.c:828\n          do_async_reclaim_metadata_space+0x110/0x364 fs/btrfs/space-info.c:1158\n          btrfs_async_reclaim_metadata_space+0x90/0xd8 fs/btrfs/space-info.c:1226\n          process_one_work+0x7e8/0x155c kernel/workqueue.c:3263\n          process_scheduled_works kernel/workqueue.c:3346 [inline]\n          worker_thread+0x958/0xed8 kernel/workqueue.c:3427\n          kthread+0x5fc/0x75c kernel/kthread.c:463\n          ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844\n\n   -> #0 (&delayed_node->mutex){+.+.}-{4:4}:\n          check_prev_add kernel/locking/lockdep.c:3165 [inline]\n          check_prevs_add kernel/locking/lockdep.c:3284 [inline]\n          validate_chain kernel/locking/lockdep.c:3908 [inline]\n          __lock_acquire+0x1774/0x30a4 kernel/locking/lockdep.c:5237\n          lock_acquire+0x14c/0x2e0 kernel/locking/lockdep.c:5868\n          __mutex_lock_common+0x1d0/0x2678 kernel/locking/mutex.c:598\n          __mutex_lock kernel/locking/mutex.c:760 [inline]\n          mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:812\n          __btrfs_release_delayed_node+0xa0/0x9b0 fs/btrfs/delayed-inode.c:290\n          btrfs_release_delayed_node fs/btrfs/delayed-inode.c:315 [inline]\n          btrfs_remove_delayed_node+0x68/0x84 fs/btrfs/delayed-inode.c:1326\n          btrfs_evict_inode+0x578/0xe28 fs/btrfs/inode.c:5587\n          evict+0x414/0x928 fs/inode.c:810\n          iput_final fs/inode.c:1914 [inline]\n          iput+0x95c/0xad4 fs/inode.c:1966\n          iget_failed+0xec/0x134 fs/bad_inode.c:248\n          btrfs_read_locked_inode+0xe1c/0x1234 fs/btrfs/inode.c:4101\n          btrfs_iget+0x1b0/0x264 fs/btrfs/inode.c:5837\n          btrfs_run_defrag_inode fs/btrfs/defrag.c:237 [inline]\n          btrfs_run_defrag_inodes+0x520/0xdc4 fs/btrf\n---truncated---"
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:  btrfs: liberar la ruta antes de iget_failed() en btrfs_read_locked_inode()  En btrfs_read_locked_inode() si no logramos buscar el inodo, saltamos a la etiqueta 'out' con una ruta que tiene una hoja bloqueada para lectura y luego llamamos a iget_failed(). Esto puede resultar en un interbloqueo ABBA, ya que iget_failed() activa el desalojo del inodo y eso causa la liberación del inodo retrasado, el cual debe bloquear el mutex del inodo retrasado, y una tarea que actualiza un inodo retrasado comienza tomando el mutex del nodo y luego modificando el btree del subvolumen del inodo.  Syzbot informó el siguiente splat de lockdep para esto: ADVERTENCIA: posible dependencia de bloqueo circular detectada    syzkaller #0 No contaminado btrfs-cleaner/8725 está intentando adquirir el bloqueo: ffff0000d6826a48 (&delayed_node->mutex){+.+.}-{4:4}, en: __btrfs_release_delayed_node+0xa0/0x9b0 fs/btrfs/delayed-inode.c:290 pero la tarea ya tiene el bloqueo: ffff0000dbeba878 (btrfs-tree-00){++++}-{4:4}, en: btrfs_tree_read_lock_nested+0x44/0x2ec fs/btrfs/locking.c:145     cuyo bloqueo ya depende del nuevo bloqueo.     la cadena de dependencia existente (en orden inverso) es:     -> #1 (btrfs-tree-00){++++}-{4:4}:           __lock_release kernel/locking/lockdep.c:5574 [en línea]           lock_release+0x198/0x39c kernel/locking/lockdep.c:5889           up_read+0x24/0x3c kernel/locking/rwsem.c:1632           btrfs_tree_read_unlock+0xdc/0x298 fs/btrfs/locking.c:169           btrfs_tree_unlock_rw fs/btrfs/locking.h:218 [en línea]           btrfs_search_slot+0xa6c/0x223c fs/btrfs/ctree.c:2133           btrfs_lookup_inode+0xd8/0x38c fs/btrfs/inode-item.c:395           __btrfs_update_delayed_inode+0x124/0xed0 fs/btrfs/delayed-inode.c:1032           btrfs_update_delayed_inode fs/btrfs/delayed-inode.c:1118 [en línea]           __btrfs_commit_inode_delayed_items+0x15f8/0x1748 fs/btrfs/delayed-inode.c:1141           __btrfs_run_delayed_items+0x1ac/0x514 fs/btrfs/delayed-inode.c:1176           btrfs_run_delayed_items_nr+0x28/0x38 fs/btrfs/delayed-inode.c:1219           flush_space+0x26c/0xb68 fs/btrfs/space-info.c:828           do_async_reclaim_metadata_space+0x110/0x364 fs/btrfs/space-info.c:1158           btrfs_async_reclaim_metadata_space+0x90/0xd8 fs/btrfs/space-info.c:1226           process_one_work+0x7e8/0x155c kernel/workqueue.c:3263 process_scheduled_works kernel/workqueue.c:3346 [en línea] worker_thread+0x958/0xed8 kernel/workqueue.c:3427           kthread+0x5fc/0x75c kernel/kthread.c:463 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844 -> #0 (&delayed_node->mutex){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3165 [en línea] check_prevs_add kernel/locking/lockdep.c:3284 [en línea] validate_chain kernel/locking/lockdep.c:3908 [en línea] __lock_acquire+0x1774/0x30a4 kernel/locking/lockdep.c:5237 lock_acquire+0x14c/0x2e0 kernel/locking/lockdep.c:5868 __mutex_lock_common+0x1d0/0x2678 kernel/locking/mutex.c:598 __mutex_lock kernel/locking/mutex.c:760 [en línea] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:812 __btrfs_release_delayed_node+0xa0/0x9b0 fs/btrfs/delayed-inode.c:290 btrfs_release_delayed_node fs/btrfs/delayed-inode.c:315 [en línea] btrfs_remove_delayed_node+0x68/0x84 fs/btrfs/delayed-inode.c:1326 btrfs_evict_inode+0x578/0xe28 fs/btrfs/inode.c:5587 evict+0x414/0x928 fs/inode.c:810 iput_final fs/inode.c:1914 [en línea] iput+0x95c/0xad4 fs/inode.c:1966 iget_failed+0xec/0x134 fs/bad_inode.c:248 btrfs_read_locked_inode+0xe1c/0x1234 fs/btrfs/inode.c:4101 btrfs_iget+0x1b0/0x264 fs/btrfs/inode.c:5837 trfs_run_defrag_inode fs/btrfs/defrag.c:237 [en línea] btrfs_run_defrag_inodes+0x520/0xdc4 fs/btrf ---truncado---"
    }
  ],
  "lastModified": "2026-06-17T10:20:45.143",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}