[PATCH 1/4] nvmet: change sn size and check validity
Max Gurtovoy
mgurtovoy at nvidia.com
Tue Apr 20 10:09:00 BST 2021
From: Noam Gottlieb <ngottlieb at nvidia.com>
According to the NVM specification, the serial_number should be 20 bytes
(bytes 23:04 of the Identify Controller data structure), and should
contain only ASCII characters.
In accordance, the serial_number size is changed to 20 bytes and before
any attempt to store a new value in serial_number we check that the
input is valid - i.e. contains only ASCII characters, is not empty and
does not exceed 20 bytes.
Reviewed-by: Max Gurtovoy <mgurtovoy at nvidia.com>
Signed-off-by: Noam Gottlieb <ngottlieb at nvidia.com>
---
drivers/nvme/target/admin-cmd.c | 4 +---
drivers/nvme/target/configfs.c | 36 ++++++++++++++++++++++++---------
drivers/nvme/target/core.c | 4 +++-
drivers/nvme/target/discovery.c | 4 +---
drivers/nvme/target/nvmet.h | 3 ++-
5 files changed, 33 insertions(+), 18 deletions(-)
diff --git a/drivers/nvme/target/admin-cmd.c b/drivers/nvme/target/admin-cmd.c
index d2a26ff3f7b3..91eb7562a88a 100644
--- a/drivers/nvme/target/admin-cmd.c
+++ b/drivers/nvme/target/admin-cmd.c
@@ -357,9 +357,7 @@ static void nvmet_execute_identify_ctrl(struct nvmet_req *req)
id->vid = 0;
id->ssvid = 0;
- memset(id->sn, ' ', sizeof(id->sn));
- bin2hex(id->sn, &ctrl->subsys->serial,
- min(sizeof(ctrl->subsys->serial), sizeof(id->sn) / 2));
+ memcpy(id->sn, ctrl->subsys->serial, NVMET_SN_MAX_SIZE);
memcpy_and_pad(id->mn, sizeof(id->mn), subsys->model_number,
strlen(subsys->model_number), ' ');
memcpy_and_pad(id->fr, sizeof(id->fr),
diff --git a/drivers/nvme/target/configfs.c b/drivers/nvme/target/configfs.c
index 65a0cf99f557..576540fdba73 100644
--- a/drivers/nvme/target/configfs.c
+++ b/drivers/nvme/target/configfs.c
@@ -1030,24 +1030,46 @@ static ssize_t nvmet_subsys_attr_version_store(struct config_item *item,
}
CONFIGFS_ATTR(nvmet_subsys_, attr_version);
+/* See Section 1.5 of NVMe 1.4 */
+static bool nvmet_is_ascii(const char c)
+{
+ return c >= 0x20 && c <= 0x7e;
+}
+
static ssize_t nvmet_subsys_attr_serial_show(struct config_item *item,
char *page)
{
struct nvmet_subsys *subsys = to_subsys(item);
- return snprintf(page, PAGE_SIZE, "%llx\n", subsys->serial);
+ return snprintf(page, PAGE_SIZE, "%s\n", subsys->serial);
}
static ssize_t nvmet_subsys_attr_serial_store(struct config_item *item,
const char *page, size_t count)
{
- u64 serial;
+ struct nvmet_subsys *subsys;
+ int pos, len;
+
+ subsys = to_subsys(item);
+ len = strcspn(page, "\n");
- if (sscanf(page, "%llx\n", &serial) != 1)
+ if (len == 0 || len > NVMET_SN_MAX_SIZE) {
+ pr_err("Serial Number can not be empty or exceed %d Bytes\n",
+ NVMET_SN_MAX_SIZE);
return -EINVAL;
+ }
+
+ for (pos = 0; pos < len; pos++) {
+ if (!nvmet_is_ascii(page[pos])) {
+ pr_err("Serial Number must contain only ASCII strings\n");
+ return -EINVAL;
+ }
+ }
down_write(&nvmet_config_sem);
- to_subsys(item)->serial = serial;
+ mutex_lock(&subsys->lock);
+ memcpy_and_pad(subsys->serial, NVMET_SN_MAX_SIZE, page, len, ' ');
+ mutex_unlock(&subsys->lock);
up_write(&nvmet_config_sem);
return count;
@@ -1128,12 +1150,6 @@ static ssize_t nvmet_subsys_attr_model_show(struct config_item *item,
return ret;
}
-/* See Section 1.5 of NVMe 1.4 */
-static bool nvmet_is_ascii(const char c)
-{
- return c >= 0x20 && c <= 0x7e;
-}
-
static ssize_t nvmet_subsys_attr_model_store_locked(struct nvmet_subsys *subsys,
const char *page, size_t count)
{
diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c
index adbede9ab7f3..3efd48b0a34e 100644
--- a/drivers/nvme/target/core.c
+++ b/drivers/nvme/target/core.c
@@ -1482,6 +1482,7 @@ struct nvmet_subsys *nvmet_subsys_alloc(const char *subsysnqn,
enum nvme_subsys_type type)
{
struct nvmet_subsys *subsys;
+ char serial[NVMET_SN_MAX_SIZE / 2];
subsys = kzalloc(sizeof(*subsys), GFP_KERNEL);
if (!subsys)
@@ -1489,7 +1490,8 @@ struct nvmet_subsys *nvmet_subsys_alloc(const char *subsysnqn,
subsys->ver = NVMET_DEFAULT_VS;
/* generate a random serial number as our controllers are ephemeral: */
- get_random_bytes(&subsys->serial, sizeof(subsys->serial));
+ get_random_bytes(&serial, sizeof(serial));
+ bin2hex(subsys->serial, &serial, sizeof(serial));
switch (type) {
case NVME_NQN_NVME:
diff --git a/drivers/nvme/target/discovery.c b/drivers/nvme/target/discovery.c
index 4845d12e374a..f39946615fd6 100644
--- a/drivers/nvme/target/discovery.c
+++ b/drivers/nvme/target/discovery.c
@@ -262,9 +262,7 @@ static void nvmet_execute_disc_identify(struct nvmet_req *req)
goto out;
}
- memset(id->sn, ' ', sizeof(id->sn));
- bin2hex(id->sn, &ctrl->subsys->serial,
- min(sizeof(ctrl->subsys->serial), sizeof(id->sn) / 2));
+ memcpy(id->sn, ctrl->subsys->serial, NVMET_SN_MAX_SIZE);
memset(id->fr, ' ', sizeof(id->fr));
memcpy_and_pad(id->mn, sizeof(id->mn), model, sizeof(model) - 1, ' ');
memcpy_and_pad(id->fr, sizeof(id->fr),
diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
index 5566ed403576..53999bd259ed 100644
--- a/drivers/nvme/target/nvmet.h
+++ b/drivers/nvme/target/nvmet.h
@@ -28,6 +28,7 @@
#define NVMET_NO_ERROR_LOC ((u16)-1)
#define NVMET_DEFAULT_CTRL_MODEL "Linux"
#define NVMET_MN_MAX_SIZE 40
+#define NVMET_SN_MAX_SIZE 20
/*
* Supported optional AENs:
@@ -229,7 +230,7 @@ struct nvmet_subsys {
u16 max_qid;
u64 ver;
- u64 serial;
+ char serial[NVMET_SN_MAX_SIZE];
char *subsysnqn;
bool pi_support;
--
2.25.4
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