2022-09-24 11:23 GMT+09:00, Atte Heikkilä <atteh.mailbox@xxxxxxxxx>:
> Case-insensitive file name lookups with __caseless_lookup() use
> strncasecmp() for file name comparison. strncasecmp() assumes an
> ISO8859-1-compatible encoding, which is not the case here as UTF-8
> is always used. As such, use of strncasecmp() here produces correct
> results only if both strings use characters in the ASCII range only.
> Fix this by using utf8_strncasecmp() if CONFIG_UNICODE is set. On
> failure or if CONFIG_UNICODE is not set, fallback to strncasecmp().
> Also, as we are adding an include for `linux/unicode.h', include it
> in `fs/ksmbd/connection.h' as well since it should be explicit there.
>
> Signed-off-by: Atte Heikkilä <atteh.mailbox@xxxxxxxxx>
> ---
> fs/ksmbd/connection.h | 1 +
> fs/ksmbd/vfs.c | 20 +++++++++++++++++---
> fs/ksmbd/vfs.h | 2 ++
> 3 files changed, 20 insertions(+), 3 deletions(-)
>
> diff --git a/fs/ksmbd/connection.h b/fs/ksmbd/connection.h
> index 41d96f5cef06..3643354a3fa7 100644
> --- a/fs/ksmbd/connection.h
> +++ b/fs/ksmbd/connection.h
> @@ -14,6 +14,7 @@
> #include <net/request_sock.h>
> #include <linux/kthread.h>
> #include <linux/nls.h>
> +#include <linux/unicode.h>
>
> #include "smb_common.h"
> #include "ksmbd_work.h"
> diff --git a/fs/ksmbd/vfs.c b/fs/ksmbd/vfs.c
> index 4fcf96a01c16..a3269df7c7b3 100644
> --- a/fs/ksmbd/vfs.c
> +++ b/fs/ksmbd/vfs.c
> @@ -1145,12 +1145,23 @@ static int __caseless_lookup(struct dir_context
> *ctx, const char *name,
> unsigned int d_type)
> {
> struct ksmbd_readdir_data *buf;
> + int cmp;
cmp should be initialized with -EINVAL to fallback strncasecmp() ?
>
> buf = container_of(ctx, struct ksmbd_readdir_data, ctx);
>
> if (buf->used != namlen)
> return 0;
> - if (!strncasecmp((char *)buf->private, name, namlen)) {
> + if (IS_ENABLED(CONFIG_UNICODE) && buf->um) {
> + const struct qstr q_buf = {.name = buf->private,
> + .len = buf->used};
> + const struct qstr q_name = {.name = name,
> + .len = namlen};
> +
> + cmp = utf8_strncasecmp(buf->um, &q_buf, &q_name);
> + }
> + if (!(IS_ENABLED(CONFIG_UNICODE) && buf->um) || cmp < 0)
I wonder why ->um is checked with CONFIG_UNICODE.
Thanks.
> + cmp = strncasecmp((char *)buf->private, name, namlen);
> + if (!cmp) {
> memcpy((char *)buf->private, name, namlen);
> buf->dirent_count = 1;
> return -EEXIST;
> @@ -1166,7 +1177,8 @@ static int __caseless_lookup(struct dir_context *ctx,
> const char *name,
> *
> * Return: 0 on success, otherwise error
> */
> -static int ksmbd_vfs_lookup_in_dir(const struct path *dir, char *name,
> size_t namelen)
> +static int ksmbd_vfs_lookup_in_dir(const struct path *dir, char *name,
> + size_t namelen, struct unicode_map *um)
> {
> int ret;
> struct file *dfilp;
> @@ -1176,6 +1188,7 @@ static int ksmbd_vfs_lookup_in_dir(const struct path
> *dir, char *name, size_t na
> .private = name,
> .used = namelen,
> .dirent_count = 0,
> + .um = um,
> };
>
> dfilp = dentry_open(dir, flags, current_cred());
> @@ -1238,7 +1251,8 @@ int ksmbd_vfs_kern_path(struct ksmbd_work *work, char
> *name,
> break;
>
> err = ksmbd_vfs_lookup_in_dir(&parent, filename,
> - filename_len);
> + filename_len,
> + work->conn->um);
> path_put(&parent);
> if (err)
> goto out;
> diff --git a/fs/ksmbd/vfs.h b/fs/ksmbd/vfs.h
> index d7542a2dab52..593059ca8511 100644
> --- a/fs/ksmbd/vfs.h
> +++ b/fs/ksmbd/vfs.h
> @@ -12,6 +12,7 @@
> #include <linux/namei.h>
> #include <uapi/linux/xattr.h>
> #include <linux/posix_acl.h>
> +#include <linux/unicode.h>
>
> #include "smbacl.h"
> #include "xattr.h"
> @@ -60,6 +61,7 @@ struct ksmbd_readdir_data {
> unsigned int used;
> unsigned int dirent_count;
> unsigned int file_attr;
> + struct unicode_map *um;
> };
>
> /* ksmbd kstat wrapper to get valid create time when reading dir entry */
> --
> 2.37.3
>
>
