5.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: Atte Heikkilä <atteh.mailbox@xxxxxxxxx>
[ Upstream commit dbab80e2071ad8c702e50dab43326608a127d27b ]
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>
Acked-by: Namjae Jeon <linkinjeon@xxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/ksmbd/connection.h | 1 +
fs/ksmbd/vfs.c | 20 +++++++++++++++++---
fs/ksmbd/vfs.h | 2 ++
3 files changed, 20 insertions(+), 3 deletions(-)
--- 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"
--- a/fs/ksmbd/vfs.c
+++ b/fs/ksmbd/vfs.c
@@ -1144,12 +1144,23 @@ static int __caseless_lookup(struct dir_
unsigned int d_type)
{
struct ksmbd_readdir_data *buf;
+ int cmp = -EINVAL;
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 (cmp < 0)
+ cmp = strncasecmp((char *)buf->private, name, namlen);
+ if (!cmp) {
memcpy((char *)buf->private, name, namlen);
buf->dirent_count = 1;
return -EEXIST;
@@ -1165,7 +1176,8 @@ static int __caseless_lookup(struct dir_
*
* 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;
@@ -1175,6 +1187,7 @@ static int ksmbd_vfs_lookup_in_dir(const
.private = name,
.used = namelen,
.dirent_count = 0,
+ .um = um,
};
dfilp = dentry_open(dir, flags, current_cred());
@@ -1237,7 +1250,8 @@ int ksmbd_vfs_kern_path(struct ksmbd_wor
break;
err = ksmbd_vfs_lookup_in_dir(&parent, filename,
- filename_len);
+ filename_len,
+ work->conn->um);
path_put(&parent);
if (err)
goto out;
--- 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"
@@ -99,6 +100,7 @@ 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 */
