Re: [PATCH v2] scsi: hpsa: Replace deprecated strncpy() with strscpy()

[Bart Van Assche]

On 2/13/25 11:53 AM, Thorsten Blum wrote:

diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
index 84d8de07b7ae..c7ebae24b09f 100644
--- a/drivers/scsi/hpsa.c
+++ b/drivers/scsi/hpsa.c
@@ -460,9 +460,8 @@ static ssize_t host_store_hp_ssd_smart_path_status(struct 
device *dev,

if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))

                return -EACCES;
-       len = count > sizeof(tmpbuf) - 1 ? sizeof(tmpbuf) - 1 : count;
-       strncpy(tmpbuf, buf, len);
-       tmpbuf[len] = '\0';
+       len = min(count + 1, sizeof(tmpbuf));
+       strscpy(tmpbuf, buf, len);
        if (sscanf(tmpbuf, "%d", &status) != 1)
                return -EINVAL;
        h = shost_to_hba(shost);
@@ -484,9 +483,8 @@ static ssize_t host_store_raid_offload_debug(struct device 
*dev,

if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))

                return -EACCES;
-       len = count > sizeof(tmpbuf) - 1 ? sizeof(tmpbuf) - 1 : count;
-       strncpy(tmpbuf, buf, len);
-       tmpbuf[len] = '\0';
+       len = min(count + 1, sizeof(tmpbuf));
+       strscpy(tmpbuf, buf, len);
        if (sscanf(tmpbuf, "%d", &debug_level) != 1)
                return -EINVAL;
        if (debug_level < 0)

Something I should have noticed earlier: this code occurs inside sysfs
write callbacks. The strings passed to sysfs write callbacks are
0-terminated. Hence, 'buf' can be passed directly to sscanf() and
tmpbuf[] can be removed. From kernfs_fop_write_iter() in fs/kernfs.c:

        buf[len] = '\0';        /* guarantee string termination */

Thanks,

Bart.