fs: move the bdex_statx call to vfs_getattr_nosec

Currently bdex_statx is only called from the very high-level
vfs_statx_path function, and thus bypassing it for in-kernel calls
to vfs_getattr or vfs_getattr_nosec.

This breaks querying the block ѕize of the underlying device in the
loop driver and also is a pitfall for any other new kernel caller.

Move the call into the lowest level helper to ensure all callers get
the right results.

Fixes: 2d985f8c6b91 ("vfs: support STATX_DIOALIGN on block devices")
Fixes: f4774e92aab8 ("loop: take the file system minimum dio alignment into account")
Reported-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/20250417064042.712140-1-hch@lst.de
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/block/bdev.c b/block/bdev.c
index 4844d1e27b6fbc2535dda62d2c2b2be67803c5bd..6a34179192c913c7cc475c7286c6884cf0261fb8 100644 (file)
--- a/block/bdev.c
+++ b/block/bdev.c
@@ -1272,8 +1272,7 @@ void sync_bdevs(bool wait)
 /*
  * Handle STATX_{DIOALIGN, WRITE_ATOMIC} for block devices.
  */
-void bdev_statx(struct path *path, struct kstat *stat,
-               u32 request_mask)
+void bdev_statx(const struct path *path, struct kstat *stat, u32 request_mask)
 {
        struct inode *backing_inode;
        struct block_device *bdev;

diff --git a/fs/stat.c b/fs/stat.c
index f13308bfdc983a1670f83ec23f235c17fb19adfc..3d9222807214a7102e7c5fc494d27fb9b205f27c 100644 (file)
--- a/fs/stat.c
+++ b/fs/stat.c
@@ -204,12 +204,25 @@ int vfs_getattr_nosec(const struct path *path, struct kstat *stat,
                                  STATX_ATTR_DAX);
 
        idmap = mnt_idmap(path->mnt);
-       if (inode->i_op->getattr)
-               return inode->i_op->getattr(idmap, path, stat,
-                                           request_mask,
-                                           query_flags);
+       if (inode->i_op->getattr) {
+               int ret;
+
+               ret = inode->i_op->getattr(idmap, path, stat, request_mask,
+                               query_flags);
+               if (ret)
+                       return ret;
+       } else {
+               generic_fillattr(idmap, request_mask, inode, stat);
+       }
+
+       /*
+        * If this is a block device inode, override the filesystem attributes
+        * with the block device specific parameters that need to be obtained
+        * from the bdev backing inode.
+        */
+       if (S_ISBLK(stat->mode))
+               bdev_statx(path, stat, request_mask);
 
-       generic_fillattr(idmap, request_mask, inode, stat);
        return 0;
 }
 EXPORT_SYMBOL(vfs_getattr_nosec);
@@ -295,15 +308,6 @@ static int vfs_statx_path(struct path *path, int flags, struct kstat *stat,
        if (path_mounted(path))
                stat->attributes |= STATX_ATTR_MOUNT_ROOT;
        stat->attributes_mask |= STATX_ATTR_MOUNT_ROOT;
-
-       /*
-        * If this is a block device inode, override the filesystem
-        * attributes with the block device specific parameters that need to be
-        * obtained from the bdev backing inode.
-        */
-       if (S_ISBLK(stat->mode))
-               bdev_statx(path, stat, request_mask);
-
        return 0;
 }
 

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index e39c45bc0a97ee18e532b0d2520fa93762fc0fe3..678dc38442bfddaa2d3c947a2fb8e0b069680381 100644 (file)
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1685,7 +1685,7 @@ int sync_blockdev(struct block_device *bdev);
 int sync_blockdev_range(struct block_device *bdev, loff_t lstart, loff_t lend);
 int sync_blockdev_nowait(struct block_device *bdev);
 void sync_bdevs(bool wait);
-void bdev_statx(struct path *, struct kstat *, u32);
+void bdev_statx(const struct path *path, struct kstat *stat, u32 request_mask);
 void printk_all_partitions(void);
 int __init early_lookup_bdev(const char *pathname, dev_t *dev);
 #else
@@ -1703,8 +1703,8 @@ static inline int sync_blockdev_nowait(struct block_device *bdev)
 static inline void sync_bdevs(bool wait)
 {
 }
-static inline void bdev_statx(struct path *path, struct kstat *stat,
-                               u32 request_mask)
+static inline void bdev_statx(const struct path *path, struct kstat *stat,
+               u32 request_mask)
 {
 }
 static inline void printk_all_partitions(void)