[PATCH RESEND] autofs: replace manual symlink buffer allocation in autofs_dir_symlink

[Thorsten Blum <thorsten.blum@linux.dev>]

The symlink name was previously duplicated using an explicit kmalloc()
followed by strcpy(), which is deprecated [1]. Replace this open-coded
string duplication with kstrdup(), which allocates and copies the
symlink name with a single helper function.

Remove the local variable 'size' and set 'i_size' directly using
strlen(cp), which is equivalent to the previous value of 'size'.

This simplifies the code, uses common string-handling helpers, and
removes the deprecated use of strcpy().

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strcpy [1]
Acked-by: Ian Kent <raven@themaw.net>
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
---
 fs/autofs/root.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/fs/autofs/root.c b/fs/autofs/root.c
index 2c31002b314a..186e960f1e23 100644
--- a/fs/autofs/root.c
+++ b/fs/autofs/root.c
@@ -7,6 +7,7 @@
 
 #include <linux/capability.h>
 #include <linux/compat.h>
+#include <linux/string.h>
 
 #include "autofs_i.h"
 
@@ -578,7 +579,6 @@ static int autofs_dir_symlink(struct mnt_idmap *idmap,
 	struct autofs_info *ino = autofs_dentry_ino(dentry);
 	struct autofs_info *p_ino;
 	struct inode *inode;
-	size_t size = strlen(symname);
 	char *cp;
 
 	pr_debug("%s <- %pd\n", symname, dentry);
@@ -589,19 +589,17 @@ static int autofs_dir_symlink(struct mnt_idmap *idmap,
 
 	autofs_del_active(dentry);
 
-	cp = kmalloc(size + 1, GFP_KERNEL);
+	cp = kstrdup(symname, GFP_KERNEL);
 	if (!cp)
 		return -ENOMEM;
 
-	strcpy(cp, symname);
-
 	inode = autofs_get_inode(dir->i_sb, S_IFLNK | 0555);
 	if (!inode) {
 		kfree(cp);
 		return -ENOMEM;
 	}
 	inode->i_private = cp;
-	inode->i_size = size;
+	inode->i_size = strlen(cp);
 
 	d_make_persistent(dentry, inode);
 	p_ino = autofs_dentry_ino(dentry->d_parent);