CVE-2026-43117: kernel: btrfs: tracepoints: get correct superblock from dentry in event btrfs_sync_file()

Severity: Critical

CVSS Score: 9.1

In the Linux kernel, the following vulnerability has been resolved: btrfs: tracepoints: get correct superblock from dentry in event btrfs_sync_file() If overlay is used on top of btrfs, dentry->d_sb translates to overlay's super block and fsid assignment will lead to a crash. Use file_inode(file)->i_sb to always get btrfs_sb.