From: Joao Martins <joao.m.martins@xxxxxxxxxx> Subject: device-dax: use struct_size() Use the struct_size() helper for the size of a struct with variable array member at the end, rather than manually calculating it. Link: https://lkml.kernel.org/r/20211202204422.26777-7-joao.m.martins@xxxxxxxxxx Suggested-by: Dan Williams <dan.j.williams@xxxxxxxxx> Signed-off-by: Joao Martins <joao.m.martins@xxxxxxxxxx> Cc: Christoph Hellwig <hch@xxxxxx> Cc: Dave Jiang <dave.jiang@xxxxxxxxx> Cc: Jane Chu <jane.chu@xxxxxxxxxx> Cc: Jason Gunthorpe <jgg@xxxxxxxxxx> Cc: Jason Gunthorpe <jgg@xxxxxxxx> Cc: John Hubbard <jhubbard@xxxxxxxxxx> Cc: Jonathan Corbet <corbet@xxxxxxx> Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Cc: Muchun Song <songmuchun@xxxxxxxxxxxxx> Cc: Naoya Horiguchi <naoya.horiguchi@xxxxxxx> Cc: Vishal Verma <vishal.l.verma@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/dax/device.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/drivers/dax/device.c~device-dax-use-struct_size +++ a/drivers/dax/device.c @@ -404,8 +404,9 @@ int dev_dax_probe(struct dev_dax *dev_da return -EINVAL; if (!pgmap) { - pgmap = devm_kzalloc(dev, sizeof(*pgmap) + sizeof(struct range) - * (dev_dax->nr_range - 1), GFP_KERNEL); + pgmap = devm_kzalloc(dev, + struct_size(pgmap, ranges, dev_dax->nr_range - 1), + GFP_KERNEL); if (!pgmap) return -ENOMEM; pgmap->nr_range = dev_dax->nr_range; _