Unverified Commit 777d0961 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Christian Brauner
Browse files

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: 2d985f8c ("vfs: support STATX_DIOALIGN on block devices")
Fixes: f4774e92 ("loop: take the file system minimum dio alignment into account")
Reported-by: default avatar"Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/20250417064042.712140-1-hch@lst.de


Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 58db1c3c

block/bdev.c

+1 −2
Original line number Diff line number Diff line
@@ -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;

fs/stat.c

+18 −14
Original line number Diff line number Diff line
@@ -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);



	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;

}

include/linux/blkdev.h

+3 −3
Original line number Diff line number Diff line
@@ -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
@@ -1703,7 +1703,7 @@ 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,

static inline void bdev_statx(const struct path *path, struct kstat *stat,

		u32 request_mask)

{

}