[PATCH 6.6 010/166] btrfs: tracepoints: get correct superblock from dentry in event btrfs_sync_file()

Greg Kroah-Hartman
2026-04-24T13:33:51Z

From: Goldwyn Rodrigues <rgoldwyn@suse.de>

[ Upstream commit a85b46db143fda5869e7d8df8f258ccef5fa1719 ]

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.

Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
include/trace/events/btrfs.h | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/include/trace/events/btrfs.h b/include/trace/events/btrfs.h
index eb762cc7bec53..2364c68df76c4 100644
--- a/include/trace/events/btrfs.h
+++ b/include/trace/events/btrfs.h
@@ -789,12 +789,15 @@ TRACE_EVENT(btrfs_sync_file,
),

TP_fast_assign(
- const struct dentry *dentry = file->f_path.dentry;
- const struct inode *inode = d_inode(dentry);
+ struct dentry *dentry = file_dentry(file);
+ struct inode *inode = file_inode(file);
+ struct dentry *parent = dget_parent(dentry);
+ struct inode *parent_inode = d_inode(parent);

- TP_fast_assign_fsid(btrfs_sb(file->f_path.dentry->d_sb));
+ dput(parent);
+ TP_fast_assign_fsid(btrfs_sb(inode->i_sb));
__entry->ino = btrfs_ino(BTRFS_I(inode));
- __entry->parent = btrfs_ino(BTRFS_I(d_inode(dentry->d_parent)));
+ __entry->parent = btrfs_ino(BTRFS_I(parent_inode));
__entry->datasync = datasync;
__entry->root_objectid =
BTRFS_I(inode)->root->root_key.objectid;
--
2.53.0