strncpy() is deprecated for use on NUL-terminated destination strings
[1] and as such we should prefer more robust and less ambiguous string
interfaces.

We don't need the NUL-padding behavior that strncpy() provides as vscsi
is NUL-allocated in ibmvscsis_probe() which proceeds to call
ibmvscsis_adapter_info():
|       vscsi = kzalloc(sizeof(*vscsi), GFP_KERNEL);

ibmvscsis_probe() -> ibmvscsis_handle_crq() -> ibmvscsis_parse_command()
-> ibmvscsis_mad() -> ibmvscsis_process_mad() -> ibmvscsis_adapter_info()

Following the same idea, `partition_name` is defiend as:
|       static char partition_name[PARTITION_NAMELEN] = "UNKNOWN";

... which is NUL-padded already, meaning strscpy() is the best option.

Considering the above, a suitable replacement is `strscpy` [2] due to
the fact that it guarantees NUL-termination on the destination buffer
without unnecessarily NUL-padding.

However, for cap->name let's use strscpy_pad as cap is allocated via
dma_alloc_coherent():
|       cap = dma_alloc_coherent(&vscsi->dma_dev->dev, olen, &token,
|                                GFP_ATOMIC);

Link: 
https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings
 [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: [email protected]
Signed-off-by: Justin Stitt <[email protected]>
---
Note: build-tested only.

Found with: $ rg "strncpy\("
---
 drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c 
b/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c
index 385f812b8793..cd223ef696e5 100644
--- a/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c
+++ b/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c
@@ -1551,17 +1551,17 @@ static long ibmvscsis_adapter_info(struct scsi_info 
*vscsi,
        if (vscsi->client_data.partition_number == 0)
                vscsi->client_data.partition_number =
                        be32_to_cpu(info->partition_number);
-       strncpy(vscsi->client_data.srp_version, info->srp_version,
+       strscpy(vscsi->client_data.srp_version, info->srp_version,
                sizeof(vscsi->client_data.srp_version));
-       strncpy(vscsi->client_data.partition_name, info->partition_name,
+       strscpy(vscsi->client_data.partition_name, info->partition_name,
                sizeof(vscsi->client_data.partition_name));
        vscsi->client_data.mad_version = be32_to_cpu(info->mad_version);
        vscsi->client_data.os_type = be32_to_cpu(info->os_type);
 
        /* Copy our info */
-       strncpy(info->srp_version, SRP_VERSION,
+       strscpy(info->srp_version, SRP_VERSION,
                sizeof(info->srp_version));
-       strncpy(info->partition_name, vscsi->dds.partition_name,
+       strscpy(info->partition_name, vscsi->dds.partition_name,
                sizeof(info->partition_name));
        info->partition_number = cpu_to_be32(vscsi->dds.partition_num);
        info->mad_version = cpu_to_be32(MAD_VERSION_1);
@@ -1645,8 +1645,8 @@ static int ibmvscsis_cap_mad(struct scsi_info *vscsi, 
struct iu_entry *iue)
                         be64_to_cpu(mad->buffer),
                         vscsi->dds.window[LOCAL].liobn, token);
        if (rc == H_SUCCESS) {
-               strncpy(cap->name, dev_name(&vscsi->dma_dev->dev),
-                       SRP_MAX_LOC_LEN);
+               strscpy_pad(cap->name, dev_name(&vscsi->dma_dev->dev),
+                       sizeof(cap->name));
 
                len = olen - min_len;
                status = VIOSRP_MAD_SUCCESS;
@@ -3650,7 +3650,7 @@ static int ibmvscsis_get_system_info(void)
 
        name = of_get_property(rootdn, "ibm,partition-name", NULL);
        if (name)
-               strncpy(partition_name, name, sizeof(partition_name));
+               strscpy(partition_name, name, sizeof(partition_name));
 
        num = of_get_property(rootdn, "ibm,partition-no", NULL);
        if (num)

---
base-commit: ffc253263a1375a65fa6c9f62a893e9767fbebfa
change-id: 
20231030-strncpy-drivers-scsi-ibmvscsi_tgt-ibmvscsi_tgt-c-8a9bd0e54666

Best regards,
--
Justin Stitt <[email protected]>


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