CVE-2026-23036

*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> btrfs: release path before iget_failed() in btrfs_read_locked_inode()<br /> <br /> In btrfs_read_locked_inode() if we fail to lookup the inode, we jump to<br /> the &amp;#39;out&amp;#39; label with a path that has a read locked leaf and then we call<br /> iget_failed(). This can result in a ABBA deadlock, since iget_failed()<br /> triggers inode eviction and that causes the release of the delayed inode,<br /> which must lock the delayed inode&amp;#39;s mutex, and a task updating a delayed<br /> inode starts by taking the node&amp;#39;s mutex and then modifying the inode&amp;#39;s<br /> subvolume btree.<br /> <br /> Syzbot reported the following lockdep splat for this:<br /> <br /> ======================================================<br /> WARNING: possible circular locking dependency detected<br /> syzkaller #0 Not tainted<br /> ------------------------------------------------------<br /> btrfs-cleaner/8725 is trying to acquire lock:<br /> ffff0000d6826a48 (&amp;delayed_node-&gt;mutex){+.+.}-{4:4}, at: __btrfs_release_delayed_node+0xa0/0x9b0 fs/btrfs/delayed-inode.c:290<br /> <br /> but task is already holding lock:<br /> ffff0000dbeba878 (btrfs-tree-00){++++}-{4:4}, at: btrfs_tree_read_lock_nested+0x44/0x2ec fs/btrfs/locking.c:145<br /> <br /> which lock already depends on the new lock.<br /> <br /> the existing dependency chain (in reverse order) is:<br /> <br /> -&gt; #1 (btrfs-tree-00){++++}-{4:4}:<br /> __lock_release kernel/locking/lockdep.c:5574 [inline]<br /> lock_release+0x198/0x39c kernel/locking/lockdep.c:5889<br /> up_read+0x24/0x3c kernel/locking/rwsem.c:1632<br /> btrfs_tree_read_unlock+0xdc/0x298 fs/btrfs/locking.c:169<br /> btrfs_tree_unlock_rw fs/btrfs/locking.h:218 [inline]<br /> btrfs_search_slot+0xa6c/0x223c fs/btrfs/ctree.c:2133<br /> btrfs_lookup_inode+0xd8/0x38c fs/btrfs/inode-item.c:395<br /> __btrfs_update_delayed_inode+0x124/0xed0 fs/btrfs/delayed-inode.c:1032<br /> btrfs_update_delayed_inode fs/btrfs/delayed-inode.c:1118 [inline]<br /> __btrfs_commit_inode_delayed_items+0x15f8/0x1748 fs/btrfs/delayed-inode.c:1141<br /> __btrfs_run_delayed_items+0x1ac/0x514 fs/btrfs/delayed-inode.c:1176<br /> btrfs_run_delayed_items_nr+0x28/0x38 fs/btrfs/delayed-inode.c:1219<br /> flush_space+0x26c/0xb68 fs/btrfs/space-info.c:828<br /> do_async_reclaim_metadata_space+0x110/0x364 fs/btrfs/space-info.c:1158<br /> btrfs_async_reclaim_metadata_space+0x90/0xd8 fs/btrfs/space-info.c:1226<br /> process_one_work+0x7e8/0x155c kernel/workqueue.c:3263<br /> process_scheduled_works kernel/workqueue.c:3346 [inline]<br /> worker_thread+0x958/0xed8 kernel/workqueue.c:3427<br /> kthread+0x5fc/0x75c kernel/kthread.c:463<br /> ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844<br /> <br /> -&gt; #0 (&amp;delayed_node-&gt;mutex){+.+.}-{4:4}:<br /> check_prev_add kernel/locking/lockdep.c:3165 [inline]<br /> check_prevs_add kernel/locking/lockdep.c:3284 [inline]<br /> validate_chain kernel/locking/lockdep.c:3908 [inline]<br /> __lock_acquire+0x1774/0x30a4 kernel/locking/lockdep.c:5237<br /> lock_acquire+0x14c/0x2e0 kernel/locking/lockdep.c:5868<br /> __mutex_lock_common+0x1d0/0x2678 kernel/locking/mutex.c:598<br /> __mutex_lock kernel/locking/mutex.c:760 [inline]<br /> mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:812<br /> __btrfs_release_delayed_node+0xa0/0x9b0 fs/btrfs/delayed-inode.c:290<br /> btrfs_release_delayed_node fs/btrfs/delayed-inode.c:315 [inline]<br /> btrfs_remove_delayed_node+0x68/0x84 fs/btrfs/delayed-inode.c:1326<br /> btrfs_evict_inode+0x578/0xe28 fs/btrfs/inode.c:5587<br /> evict+0x414/0x928 fs/inode.c:810<br /> iput_final fs/inode.c:1914 [inline]<br /> iput+0x95c/0xad4 fs/inode.c:1966<br /> iget_failed+0xec/0x134 fs/bad_inode.c:248<br /> btrfs_read_locked_inode+0xe1c/0x1234 fs/btrfs/inode.c:4101<br /> btrfs_iget+0x1b0/0x264 fs/btrfs/inode.c:5837<br /> btrfs_run_defrag_inode fs/btrfs/defrag.c:237 [inline]<br /> btrfs_run_defrag_inodes+0x520/0xdc4 fs/btrf<br /> ---truncated---