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

Ian Kent
2026-01-27T02:14:12Z

On 27/1/26 09:36, Thorsten Blum wrote:
> 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]
> 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);

Looks fine to me.

Acked by: Ian Kent <raven@themaw.net>

Christian, is there anything else I need to do for this?

Ian