| Message ID | 20231030-strncpy-drivers-scsi-ibmvscsi-ibmvscsi-c-v1-1-f8b06ae9e3d5@google.com |
|---|---|
| State | New |
| Headers | show |
| Series | scsi: ibmvscsi: replace deprecated strncpy with strscpy | expand |
On Mon, Oct 30, 2023 at 08:40:48PM +0000, Justin Stitt wrote: > 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 partition_name to be NUL-terminated based on its usage with > format strings: > | dev_info(hostdata->dev, "host srp version: %s, " > | "host partition %s (%d), OS %d, max io %u\n", > | hostdata->madapter_info.srp_version, > | hostdata->madapter_info.partition_name, > | be32_to_cpu(hostdata->madapter_info.partition_number), > | be32_to_cpu(hostdata->madapter_info.os_type), > | be32_to_cpu(hostdata->madapter_info.port_max_txu[0])); > ... > | len = snprintf(buf, PAGE_SIZE, "%s\n", > | hostdata->madapter_info.partition_name); > > Moreover, NUL-padding is not required as madapter_info is explicitly > memset to 0: > | memset(&hostdata->madapter_info, 0x00, > | sizeof(hostdata->madapter_info)); > > 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. > > 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: linux-hardening@vger.kernel.org > Signed-off-by: Justin Stitt <justinstitt@google.com> Agreed; this conversion looks correct to me too. Reviewed-by: Kees Cook <keescook@chromium.org>
On Mon, 30 Oct 2023 20:40:48 +0000, Justin Stitt wrote: > 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 partition_name to be NUL-terminated based on its usage with > format strings: > | dev_info(hostdata->dev, "host srp version: %s, " > | "host partition %s (%d), OS %d, max io %u\n", > | hostdata->madapter_info.srp_version, > | hostdata->madapter_info.partition_name, > | be32_to_cpu(hostdata->madapter_info.partition_number), > | be32_to_cpu(hostdata->madapter_info.os_type), > | be32_to_cpu(hostdata->madapter_info.port_max_txu[0])); > ... > | len = snprintf(buf, PAGE_SIZE, "%s\n", > | hostdata->madapter_info.partition_name); > > [...] Applied to 6.8/scsi-queue, thanks! [1/1] scsi: ibmvscsi: replace deprecated strncpy with strscpy https://git.kernel.org/mkp/scsi/c/712b3f43ba0e
diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c index 59599299615d..71f3e9563520 100644 --- a/drivers/scsi/ibmvscsi/ibmvscsi.c +++ b/drivers/scsi/ibmvscsi/ibmvscsi.c @@ -266,7 +266,7 @@ static void set_adapter_info(struct ibmvscsi_host_data *hostdata) dev_info(hostdata->dev, "SRP_VERSION: %s\n", SRP_VERSION); strcpy(hostdata->madapter_info.srp_version, SRP_VERSION); - strncpy(hostdata->madapter_info.partition_name, partition_name, + strscpy(hostdata->madapter_info.partition_name, partition_name, sizeof(hostdata->madapter_info.partition_name)); hostdata->madapter_info.partition_number =
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 partition_name to be NUL-terminated based on its usage with format strings: | dev_info(hostdata->dev, "host srp version: %s, " | "host partition %s (%d), OS %d, max io %u\n", | hostdata->madapter_info.srp_version, | hostdata->madapter_info.partition_name, | be32_to_cpu(hostdata->madapter_info.partition_number), | be32_to_cpu(hostdata->madapter_info.os_type), | be32_to_cpu(hostdata->madapter_info.port_max_txu[0])); ... | len = snprintf(buf, PAGE_SIZE, "%s\n", | hostdata->madapter_info.partition_name); Moreover, NUL-padding is not required as madapter_info is explicitly memset to 0: | memset(&hostdata->madapter_info, 0x00, | sizeof(hostdata->madapter_info)); 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. 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: linux-hardening@vger.kernel.org Signed-off-by: Justin Stitt <justinstitt@google.com> --- Note: build-tested only. Found with: $ rg "strncpy\(" --- drivers/scsi/ibmvscsi/ibmvscsi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- base-commit: ffc253263a1375a65fa6c9f62a893e9767fbebfa change-id: 20231030-strncpy-drivers-scsi-ibmvscsi-ibmvscsi-c-3b5019ce50ad Best regards, -- Justin Stitt <justinstitt@google.com>