snprintf() does not return negative values on error. To know if the buffer was too small, the returned value should be compared with the length of the passed buffer. If it is bigger or equal, then the output has been truncated. Update the test for truncation accordingly. Also return -ENOMEM in such a case, as already done below in the same functions. Fixes: 8765c5ba1949 ("ACPI / scan: Rework modalias creation when "compatible" is present") Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx> --- drivers/acpi/device_sysfs.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/acpi/device_sysfs.c b/drivers/acpi/device_sysfs.c index 9d8e90744cb5..4deb36dccb73 100644 --- a/drivers/acpi/device_sysfs.c +++ b/drivers/acpi/device_sysfs.c @@ -158,8 +158,8 @@ static int create_pnp_modalias(const struct acpi_device *acpi_dev, char *modalia return 0; len = snprintf(modalias, size, "acpi:"); - if (len <= 0) - return len; + if (len >= size) + return -ENOMEM; size -= len; @@ -212,8 +212,8 @@ static int create_of_modalias(const struct acpi_device *acpi_dev, char *modalias len = snprintf(modalias, size, "of:N%sT", (char *)buf.pointer); ACPI_FREE(buf.pointer); - if (len <= 0) - return len; + if (len >= size) + return -ENOMEM; of_compatible = acpi_dev->data.of_compatible; if (of_compatible->type == ACPI_TYPE_PACKAGE) { -- 2.32.0