4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Toshi Kani <toshi.kani@xxxxxxx> commit 4e3f0701f25ab194c5362576b1146a1e6cc6c2e7 upstream. __add_badblock_range() does not account sector alignment when it sets 'num_sectors'. Therefore, an ARS error record range spanning across two sectors is set to a single sector length, which leaves the 2nd sector unprotected. Change __add_badblock_range() to set 'num_sectors' properly. Fixes: 0caeef63e6d2 ("libnvdimm: Add a poison list and export badblocks") Signed-off-by: Toshi Kani <toshi.kani@xxxxxxx> Reviewed-by: Vishal Verma <vishal.l.verma@xxxxxxxxx> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/nvdimm/core.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) --- a/drivers/nvdimm/core.c +++ b/drivers/nvdimm/core.c @@ -450,14 +450,15 @@ static void set_badblock(struct badblock static void __add_badblock_range(struct badblocks *bb, u64 ns_offset, u64 len) { const unsigned int sector_size = 512; - sector_t start_sector; + sector_t start_sector, end_sector; u64 num_sectors; u32 rem; start_sector = div_u64(ns_offset, sector_size); - num_sectors = div_u64_rem(len, sector_size, &rem); + end_sector = div_u64_rem(ns_offset + len, sector_size, &rem); if (rem) - num_sectors++; + end_sector++; + num_sectors = end_sector - start_sector; if (unlikely(num_sectors > (u64)INT_MAX)) { u64 remaining = num_sectors;