Ensuring we don't truncate loff_t when casting to sector_t is done in multiple places; factor it out. Signed-off-by: Martijn Coenen <maco@xxxxxxxxxxx> --- drivers/block/loop.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-) diff --git a/drivers/block/loop.c b/drivers/block/loop.c index f1754262fc94..396b8bd4d75c 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -228,15 +228,30 @@ static void __loop_update_dio(struct loop_device *lo, bool dio) blk_mq_unfreeze_queue(lo->lo_queue); } +/** + * loop_validate_size() - validates that the passed in size fits in a sector_t + * @size: size to validate + */ +static int +loop_validate_size(loff_t size) +{ + if ((loff_t)(sector_t)size != size) + return -EFBIG; + + return 0; +} + static int figure_loop_size(struct loop_device *lo, loff_t offset, loff_t sizelimit) { + int err; loff_t size = get_size(offset, sizelimit, lo->lo_backing_file); - sector_t x = (sector_t)size; struct block_device *bdev = lo->lo_device; - if (unlikely((loff_t)x != size)) - return -EFBIG; + err = loop_validate_size(size); + if (err) + return err; + if (lo->lo_offset != offset) lo->lo_offset = offset; if (lo->lo_sizelimit != sizelimit) @@ -1003,9 +1018,9 @@ static int loop_set_fd(struct loop_device *lo, fmode_t mode, !file->f_op->write_iter) lo_flags |= LO_FLAGS_READ_ONLY; - error = -EFBIG; size = get_loop_size(lo, file); - if ((loff_t)(sector_t)size != size) + error = loop_validate_size(size); + if (error) goto out_unlock; error = loop_prepare_queue(lo); if (error) -- 2.26.2.303.gf8c07b1a785-goog