Various files: strncpy()->sprintf(), reduce strlen()'s

strncpy may not be very efficient for short strings copied into
a large buffer: If the length of src is less than n,
strncpy() writes additional null bytes to dest to ensure
that a total of n bytes are written.

Instead, use snprintf(). Check for truncated output
where applicable.

Also:
- save the result of strlen() and re-use it when possible.
- move from strlen to SLEN (sizeof() ) for const strings.

Compile-tested only!

Change-Id: I54e80d4f4a80e98d3775e376efe05c51af0b29eb
updates: bz#1193929
Signed-off-by: Yaniv Kaul <ykaul@redhat.com>

3 files changed, 15 insertions, 4 deletions

diff --git a/xlators/features/locks/src/posix.c b/xlators/features/locks/src/posix.c
index c4ca71cfd7f..22d5990275d 100644
--- a/xlators/features/locks/src/posix.c
+++ b/xlators/features/locks/src/posix.c
@@ -1062,7 +1062,7 @@ pl_getxattr (call_frame_t *frame, xlator_t *this, loc_t *loc,
         if (!name)
                 goto usual;
 
-        if (strncmp (name, GF_XATTR_CLRLK_CMD, strlen (GF_XATTR_CLRLK_CMD)))
+        if (strncmp (name, GF_XATTR_CLRLK_CMD, SLEN (GF_XATTR_CLRLK_CMD)))
                 goto usual;
 
         if (clrlk_parse_args (name, &args)) {
@@ -1136,7 +1136,10 @@ pl_getxattr (call_frame_t *frame, xlator_t *this, loc_t *loc,
                 goto out;
         }
 
-        strncpy (key, name, strlen (name));
+        if (snprintf (key, sizeof (key), "%s", name) >= sizeof (key)) {
+                op_ret = -1;
+                goto out;
+        }
         if (dict_set_dynstr (dict, key, lk_summary)) {
                 op_ret = -1;
                 op_errno = ENOMEM;
diff --git a/xlators/features/marker/src/marker-quota-helper.c b/xlators/features/marker/src/marker-quota-helper.c
index e3e218f8af5..92d4094e7f8 100644
--- a/xlators/features/marker/src/marker-quota-helper.c
+++ b/xlators/features/marker/src/marker-quota-helper.c
@@ -297,7 +297,11 @@ mq_dict_set_contribution (xlator_t *this, dict_t *dict, loc_t *loc,
                 goto out;
 
         if (contri_key)
-                strncpy (contri_key, key, QUOTA_KEY_MAX);
+                if (snprintf(contri_key, QUOTA_KEY_MAX, "%s", key)
+                    >= QUOTA_KEY_MAX) {
+                        ret = -1;
+                        goto out;
+                }
 
 out:
         if (ret < 0)
diff --git a/xlators/features/marker/src/marker-quota.c b/xlators/features/marker/src/marker-quota.c
index f6a0df810bc..620201d616e 100644
--- a/xlators/features/marker/src/marker-quota.c
+++ b/xlators/features/marker/src/marker-quota.c
@@ -2169,7 +2169,11 @@ mq_req_xattr (xlator_t *this, loc_t *loc, dict_t *dict,
         if (ret < 0)
                 goto out;
         if (size_key)
-                strncpy (size_key, key, QUOTA_KEY_MAX);
+                if (snprintf (size_key, QUOTA_KEY_MAX, "%s", key)
+                    >= QUOTA_KEY_MAX) {
+                        ret = -1;
+                        goto out;
+                }
 
         ret = dict_set_uint64 (dict, key, 0);
         if (ret < 0)