[PATCH v2] btrfs: rcu_string: Replace strncpy() with strscpy()

[Artem Chernyshev]

Using strncpy() on NUL-terminated strings are deprecated.
To avoid possible forming of non-terminated string
strscpy() could be used.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 606686eeac45 ("Btrfs: use rcu to protect device->name")
Signed-off-by: Artem Chernyshev <artem.chernyshev@xxxxxxxxxxx>
---
V1->V2 Fixed typo in subject

 fs/btrfs/rcu-string.h | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/rcu-string.h b/fs/btrfs/rcu-string.h
index 5c1a617eb25d..d9894da7a05a 100644
--- a/fs/btrfs/rcu-string.h
+++ b/fs/btrfs/rcu-string.h
@@ -18,7 +18,10 @@ static inline struct rcu_string *rcu_string_strdup(const char *src, gfp_t mask)
 					 (len * sizeof(char)), mask);
 	if (!ret)
 		return ret;
-	strncpy(ret->str, src, len);
+	if (WARN_ON(strscpy(ret->str, src, len) < 0)) {
+		kfree(ret);
+		return NULL;
+	}
 	return ret;
 }
 
-- 
2.30.3