nvmet: don't report 0-bytes in serial number

The NVME standard mandates that the SN, MN, and FR fields of the Identify
Controller Data Structure be "ASCII strings".  That means that they may
not contain 0-bytes, not even string terminators.

Signed-off-by: Martin Wilck <mwilck@suse.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
[hch: fixed for the move of the serial field, updated description]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Martin Wilck 2017-07-14 00:25:31 +02:00 committed by Jens Axboe
parent fcbc545959
commit 42de82a8b5

View File

@ -168,11 +168,21 @@ static void nvmet_execute_get_log_page(struct nvmet_req *req)
nvmet_req_complete(req, status);
}
static void copy_and_pad(char *dst, int dst_len, const char *src, int src_len)
{
int len = min(src_len, dst_len);
memcpy(dst, src, len);
if (dst_len > len)
memset(dst + len, ' ', dst_len - len);
}
static void nvmet_execute_identify_ctrl(struct nvmet_req *req)
{
struct nvmet_ctrl *ctrl = req->sq->ctrl;
struct nvme_id_ctrl *id;
u16 status = 0;
const char model[] = "Linux";
id = kzalloc(sizeof(*id), GFP_KERNEL);
if (!id) {
@ -184,8 +194,10 @@ static void nvmet_execute_identify_ctrl(struct nvmet_req *req)
id->vid = 0;
id->ssvid = 0;
memset(id->sn, ' ', sizeof(id->sn));
snprintf(id->sn, sizeof(id->sn), "%llx", ctrl->subsys->serial);
bin2hex(id->sn, &ctrl->subsys->serial,
min(sizeof(ctrl->subsys->serial), sizeof(id->sn) / 2));
copy_and_pad(id->mn, sizeof(id->mn), model, sizeof(model) - 1);
copy_and_pad(id->fr, sizeof(id->fr), UTS_RELEASE, strlen(UTS_RELEASE));
memset(id->mn, ' ', sizeof(id->mn));
strncpy((char *)id->mn, "Linux", sizeof(id->mn));