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

Based on the deliberate `sizeof(dest) ... - 1` pattern we can see that
both dump_info->dev_human_readable and dump_info->bus_human_readable are
intended to be NUL-terminated.

Moreover, since this seems to cross the file boundary let's NUL-pad to
ensure no behavior change.

strscpy_pad() covers both the NUL-termination and NUL-padding, let's use
it.

Link: 
https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings
 [1]
Link: https://github.com/KSPP/linux/issues/90
Cc: [email protected]
Signed-off-by: Justin Stitt <[email protected]>
---
Changes in v2:
- prefer strscpy_pad (thanks Kees)
- Link to v1: 
https://lore.kernel.org/r/20231017-strncpy-drivers-net-wireless-intel-iwlwifi-fw-dbg-c-v1-1-bf69ec7d1...@google.com
---
Note: build-tested only.

Found with: $ rg "strncpy\("
---
 drivers/net/wireless/intel/iwlwifi/fw/dbg.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/fw/dbg.c 
b/drivers/net/wireless/intel/iwlwifi/fw/dbg.c
index 3ab6a68f1e9f..7aa282592cdc 100644
--- a/drivers/net/wireless/intel/iwlwifi/fw/dbg.c
+++ b/drivers/net/wireless/intel/iwlwifi/fw/dbg.c
@@ -880,10 +880,10 @@ iwl_fw_error_dump_file(struct iwl_fw_runtime *fwrt,
                        cpu_to_le32(fwrt->trans->hw_rev_step);
                memcpy(dump_info->fw_human_readable, fwrt->fw->human_readable,
                       sizeof(dump_info->fw_human_readable));
-               strncpy(dump_info->dev_human_readable, fwrt->trans->name,
-                       sizeof(dump_info->dev_human_readable) - 1);
-               strncpy(dump_info->bus_human_readable, fwrt->dev->bus->name,
-                       sizeof(dump_info->bus_human_readable) - 1);
+               strscpy_pad(dump_info->dev_human_readable, fwrt->trans->name,
+                       sizeof(dump_info->dev_human_readable));
+               strscpy_pad(dump_info->bus_human_readable, fwrt->dev->bus->name,
+                       sizeof(dump_info->bus_human_readable));
                dump_info->num_of_lmacs = fwrt->smem_cfg.num_lmacs;
                dump_info->lmac_err_id[0] =
                        cpu_to_le32(fwrt->dump.lmac_err_id[0]);

---
base-commit: 58720809f52779dc0f08e53e54b014209d13eebb
change-id: 
20231017-strncpy-drivers-net-wireless-intel-iwlwifi-fw-dbg-c-1f49f00b8a2e

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


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