Unverified Commit a311a08a authored by Darrick J. Wong's avatar Darrick J. Wong Committed by Christian Brauner
Browse files

iomap: constrain the file range passed to iomap_file_unshare 



File contents can only be shared (i.e. reflinked) below EOF, so it makes
no sense to try to unshare ranges beyond EOF.  Constrain the file range
parameters here so that we don't have to do that in the callers.

Fixes: 5f4e5752 ("fs: add iomap_file_dirty")
Signed-off-by: default avatarDarrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20241002150213.GC21853@frogsfrogsfrogs


Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarBrian Foster <bfoster@redhat.com>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent f7a4874d

fs/dax.c

+5 −1
Original line number Diff line number Diff line
@@ -1305,11 +1305,15 @@ int dax_file_unshare(struct inode *inode, loff_t pos, loff_t len, 
	struct iomap_iter iter = {

		.inode		= inode,

		.pos		= pos,

		.len		= len,

		.flags		= IOMAP_WRITE | IOMAP_UNSHARE | IOMAP_DAX,

	};

	loff_t size = i_size_read(inode);

	int ret;



	if (pos < 0 || pos >= size)

		return 0;



	iter.len = min(len, size - pos);

	while ((ret = iomap_iter(&iter, ops)) > 0)

		iter.processed = dax_unshare_iter(&iter);

	return ret;

fs/iomap/buffered-io.c

+5 −1
Original line number Diff line number Diff line
@@ -1375,11 +1375,15 @@ iomap_file_unshare(struct inode *inode, loff_t pos, loff_t len, 
	struct iomap_iter iter = {

		.inode		= inode,

		.pos		= pos,

		.len		= len,

		.flags		= IOMAP_WRITE | IOMAP_UNSHARE,

	};

	loff_t size = i_size_read(inode);

	int ret;



	if (pos < 0 || pos >= size)

		return 0;



	iter.len = min(len, size - pos);

	while ((ret = iomap_iter(&iter, ops)) > 0)

		iter.processed = iomap_unshare_iter(&iter);

	return ret;