From: Colin Ian King <colin.k...@canonical.com> The shifting of the u8 integer buf[3] by 24 bits to the left will be promoted to a 32 bit signed int and then sign-extended to a u64. In the event that the top bit of buf[3] is set then all then all the upper 32 bits of the u64 end up as also being set because of the sign-extension. Fix this by casting buf[i] to a u64 before the shift.
Addresses-Coverity: ("Unintended sign extension") Fixes: 097eb1136ebb ("nvmem: core: Add functions to make number reading easy") Signed-off-by: Colin Ian King <colin.k...@canonical.com> Reviewed-by: Douglas Anderson <diand...@chromium.org> Signed-off-by: Srinivas Kandagatla <srinivas.kandaga...@linaro.org> --- drivers/nvmem/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c index 635e3131eb5f..bca671ff4e54 100644 --- a/drivers/nvmem/core.c +++ b/drivers/nvmem/core.c @@ -1693,7 +1693,7 @@ int nvmem_cell_read_variable_le_u64(struct device *dev, const char *cell_id, /* Copy w/ implicit endian conversion */ *val = 0; for (i = 0; i < len; i++) - *val |= buf[i] << (8 * i); + *val |= (uint64_t)buf[i] << (8 * i); kfree(buf); -- 2.21.0