5.15-stable review patch. If anyone has any objections, please let me know.
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From: Atte Heikkilä atteh.mailbox@gmail.com
[ 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@gmail.com Acked-by: Namjae Jeon linkinjeon@kernel.org Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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 */