Building arm:allmodconfig may fail with the following error. In function 'fortify_memcpy_chk', inlined from 'bitmap_copy' at include/linux/bitmap.h:261:2, inlined from 'bitmap_copy_clear_tail' at include/linux/bitmap.h:270:2, inlined from 'bitmap_from_u64' at include/linux/bitmap.h:622:2, inlined from 'check_populated_dimms' at drivers/hwmon/peci/dimmtemp.c:284:2: include/linux/fortify-string.h:344:25: error: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter) The problematic code is bitmap_from_u64(priv->dimm_mask, dimm_mask); dimm_mask is declared as u64, but the bitmap in priv->dimm_mask is only 24 bit wide. On 32-bit systems, this results in writes over the end of the bitmap. Fix the problem by using u32 instead of u64 for dimm_mask. This is currently sufficient, and a compile time check to ensure that the number of dimms does not exceed the bit map size is already in place. Fixes: 73bc1b885dae ("hwmon: peci: Add dimmtemp driver") Cc: Iwona Winiarska <iwona.winiarska@xxxxxxxxx> Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx> --- drivers/hwmon/peci/dimmtemp.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/hwmon/peci/dimmtemp.c b/drivers/hwmon/peci/dimmtemp.c index 3c71b5546bcb..0a633bda3668 100644 --- a/drivers/hwmon/peci/dimmtemp.c +++ b/drivers/hwmon/peci/dimmtemp.c @@ -220,7 +220,7 @@ static int check_populated_dimms(struct peci_dimmtemp *priv) int chan_rank_max = priv->gen_info->chan_rank_max; int dimm_idx_max = priv->gen_info->dimm_idx_max; u32 chan_rank_empty = 0; - u64 dimm_mask = 0; + u32 dimm_mask = 0; int chan_rank, dimm_idx, ret; u32 pcs; @@ -279,9 +279,9 @@ static int check_populated_dimms(struct peci_dimmtemp *priv) return -EAGAIN; } - dev_dbg(priv->dev, "Scanned populated DIMMs: %#llx\n", dimm_mask); + dev_dbg(priv->dev, "Scanned populated DIMMs: %#x\n", dimm_mask); - bitmap_from_u64(priv->dimm_mask, dimm_mask); + bitmap_from_arr32(priv->dimm_mask, &dimm_mask, DIMM_NUMS_MAX); return 0; } -- 2.35.1