[PATCH] vfs: Replace all non-returning strlcpy with strscpy

[Azeem Shaikh]

strlcpy() reads the entire source buffer first.
This read may exceed the destination size limit.
This is both inefficient and can lead to linear read
overflows if a source string is not NUL-terminated [1].
In an effort to remove strlcpy() completely [2], replace
strlcpy() here with strscpy().
No return values were used, so direct replacement is safe.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89

Signed-off-by: Azeem Shaikh <azeemshaikh38@xxxxxxxxx>
---
 fs/char_dev.c |    2 +-
 fs/super.c    |    4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/char_dev.c b/fs/char_dev.c
index 13deb45f1ec6..950b6919fb87 100644
--- a/fs/char_dev.c
+++ b/fs/char_dev.c
@@ -150,7 +150,7 @@ __register_chrdev_region(unsigned int major, unsigned int baseminor,
 	cd->major = major;
 	cd->baseminor = baseminor;
 	cd->minorct = minorct;
-	strlcpy(cd->name, name, sizeof(cd->name));
+	strscpy(cd->name, name, sizeof(cd->name));
 
 	if (!prev) {
 		cd->next = curr;
diff --git a/fs/super.c b/fs/super.c
index 34afe411cf2b..8d8d68799b34 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -595,7 +595,7 @@ struct super_block *sget_fc(struct fs_context *fc,
 	fc->s_fs_info = NULL;
 	s->s_type = fc->fs_type;
 	s->s_iflags |= fc->s_iflags;
-	strlcpy(s->s_id, s->s_type->name, sizeof(s->s_id));
+	strscpy(s->s_id, s->s_type->name, sizeof(s->s_id));
 	list_add_tail(&s->s_list, &super_blocks);
 	hlist_add_head(&s->s_instances, &s->s_type->fs_supers);
 	spin_unlock(&sb_lock);
@@ -674,7 +674,7 @@ struct super_block *sget(struct file_system_type *type,
 		return ERR_PTR(err);
 	}
 	s->s_type = type;
-	strlcpy(s->s_id, type->name, sizeof(s->s_id));
+	strscpy(s->s_id, type->name, sizeof(s->s_id));
 	list_add_tail(&s->s_list, &super_blocks);
 	hlist_add_head(&s->s_instances, &type->fs_supers);
 	spin_unlock(&sb_lock);