scsi: bnx2fc: Replace deprecated strncpy() with strscpy()

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 expect hba->chip_num to be NUL-terminated based on its usage with format
strings:

	snprintf(fc_host_symbolic_name(lport->host), 256,
		 "%s (QLogic %s) v%s over %s",
		BNX2FC_NAME, hba->chip_num, BNX2FC_VERSION,
		interface->netdev->name);

Moreover, NUL-padding is not required as hba is zero-allocated from its
callsite:

	hba = kzalloc(sizeof(*hba), GFP_KERNEL);

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.

Regarding stats_addr->version, I've opted to also use strscpy() instead of
strscpy_pad() as I typically see these XYZ_get_strings() pass
zero-allocated data. I couldn't track all of where bnx2fc_ulp_get_stats()
is used and if required, we could opt for strscpy_pad().

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Link: https://lore.kernel.org/r/20231023-strncpy-drivers-scsi-bnx2fc-bnx2fc_fcoe-c-v1-1-a3736943cde2@google.com
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/bnx2fc/bnx2fc_fcoe.c b/drivers/scsi/bnx2fc/bnx2fc_fcoe.c
index 05ddbb9bb7d8aa2ca269e738d93e18f2e2899f01..3ebfb09329ad8875208a9760cde5c4fa0da8499e 100644 (file)
--- a/drivers/scsi/bnx2fc/bnx2fc_fcoe.c
+++ b/drivers/scsi/bnx2fc/bnx2fc_fcoe.c
@@ -1737,32 +1737,32 @@ static int bnx2fc_bind_pcidev(struct bnx2fc_hba *hba)
 
        switch (pdev->device) {
        case PCI_DEVICE_ID_NX2_57710:
-               strncpy(hba->chip_num, "BCM57710", BCM_CHIP_LEN);
+               strscpy(hba->chip_num, "BCM57710", sizeof(hba->chip_num));
                break;
        case PCI_DEVICE_ID_NX2_57711:
-               strncpy(hba->chip_num, "BCM57711", BCM_CHIP_LEN);
+               strscpy(hba->chip_num, "BCM57711", sizeof(hba->chip_num));
                break;
        case PCI_DEVICE_ID_NX2_57712:
        case PCI_DEVICE_ID_NX2_57712_MF:
        case PCI_DEVICE_ID_NX2_57712_VF:
-               strncpy(hba->chip_num, "BCM57712", BCM_CHIP_LEN);
+               strscpy(hba->chip_num, "BCM57712", sizeof(hba->chip_num));
                break;
        case PCI_DEVICE_ID_NX2_57800:
        case PCI_DEVICE_ID_NX2_57800_MF:
        case PCI_DEVICE_ID_NX2_57800_VF:
-               strncpy(hba->chip_num, "BCM57800", BCM_CHIP_LEN);
+               strscpy(hba->chip_num, "BCM57800", sizeof(hba->chip_num));
                break;
        case PCI_DEVICE_ID_NX2_57810:
        case PCI_DEVICE_ID_NX2_57810_MF:
        case PCI_DEVICE_ID_NX2_57810_VF:
-               strncpy(hba->chip_num, "BCM57810", BCM_CHIP_LEN);
+               strscpy(hba->chip_num, "BCM57810", sizeof(hba->chip_num));
                break;
        case PCI_DEVICE_ID_NX2_57840:
        case PCI_DEVICE_ID_NX2_57840_MF:
        case PCI_DEVICE_ID_NX2_57840_VF:
        case PCI_DEVICE_ID_NX2_57840_2_20:
        case PCI_DEVICE_ID_NX2_57840_4_10:
-               strncpy(hba->chip_num, "BCM57840", BCM_CHIP_LEN);
+               strscpy(hba->chip_num, "BCM57840", sizeof(hba->chip_num));
                break;
        default:
                pr_err(PFX "Unknown device id 0x%x\n", pdev->device);
@@ -1800,7 +1800,7 @@ static int bnx2fc_ulp_get_stats(void *handle)
        if (!stats_addr)
                return -EINVAL;
 
-       strncpy(stats_addr->version, BNX2FC_VERSION,
+       strscpy(stats_addr->version, BNX2FC_VERSION,
                sizeof(stats_addr->version));
        stats_addr->txq_size = BNX2FC_SQ_WQES_MAX;
        stats_addr->rxq_size = BNX2FC_CQ_WQES_MAX;