From: Colin Ian King <colin.king@xxxxxxxxxxxxx> Shifting a u8 left will cause the value to be promoted to an integer. If the top bit of the u8 is set then the following conversion to a 64 bit resource_size_t will sign extend the value causing the upper 32 bits to be set in the result. Fix this by casting the u8 value to a resource_size_t before the shift. Original commit is pre-git history. Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx> --- drivers/pnp/isapnp/core.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/drivers/pnp/isapnp/core.c b/drivers/pnp/isapnp/core.c index 179b737280e1..c947b1673041 100644 --- a/drivers/pnp/isapnp/core.c +++ b/drivers/pnp/isapnp/core.c @@ -511,10 +511,14 @@ static void __init isapnp_parse_mem32_resource(struct pnp_dev *dev, unsigned char flags; isapnp_peek(tmp, size); - min = (tmp[4] << 24) | (tmp[3] << 16) | (tmp[2] << 8) | tmp[1]; - max = (tmp[8] << 24) | (tmp[7] << 16) | (tmp[6] << 8) | tmp[5]; - align = (tmp[12] << 24) | (tmp[11] << 16) | (tmp[10] << 8) | tmp[9]; - len = (tmp[16] << 24) | (tmp[15] << 16) | (tmp[14] << 8) | tmp[13]; + min = ((resource_size_t)tmp[4] << 24) | (tmp[3] << 16) | + (tmp[2] << 8) | tmp[1]; + max = ((resource_size_t)tmp[8] << 24) | (tmp[7] << 16) | + (tmp[6] << 8) | tmp[5]; + align = ((resource_size_t)tmp[12] << 24) | (tmp[11] << 16) | + (tmp[10] << 8) | tmp[9]; + len = ((resource_size_t)tmp[16] << 24) | (tmp[15] << 16) | + (tmp[14] << 8) | tmp[13]; flags = tmp[0]; pnp_register_mem_resource(dev, option_flags, min, max, align, len, flags); @@ -532,8 +536,10 @@ static void __init isapnp_parse_fixed_mem32_resource(struct pnp_dev *dev, unsigned char flags; isapnp_peek(tmp, size); - base = (tmp[4] << 24) | (tmp[3] << 16) | (tmp[2] << 8) | tmp[1]; - len = (tmp[8] << 24) | (tmp[7] << 16) | (tmp[6] << 8) | tmp[5]; + base = ((resource_size_t)tmp[4] << 24) | (tmp[3] << 16) | + (tmp[2] << 8) | tmp[1]; + len = ((resource_size_t)tmp[8] << 24) | (tmp[7] << 16) | + (tmp[6] << 8) | tmp[5]; flags = tmp[0]; pnp_register_mem_resource(dev, option_flags, base, base, 0, len, flags); } -- 2.20.1
