From 93310053663ba647e402ef67e4bb18ec06ff8dc4 Mon Sep 17 00:00:00 2001 From: Philipp Kerling Date: Sun, 8 Jun 2025 20:59:00 +0200 Subject: [PATCH] smb: client: disable path remapping with POSIX extensions If SMB 3.1.1 POSIX Extensions are available and negotiated, the client should be able to use all characters and not remap anything. Currently, the user has to explicitly request this behavior by specifying the "nomapposix" mount option. Link: https://lore.kernel.org/4195bb677b33d680e77549890a4f4dd3b474ceaf.camel@rx2.rx-server.de Signed-off-by: Philipp Kerling Reviewed-by: Namjae Jeon Signed-off-by: Steve French --- Documentation/admin-guide/cifs/usage.rst | 2 ++ fs/smb/client/connect.c | 10 ++++++++-- 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/Documentation/admin-guide/cifs/usage.rst b/Documentation/admin-guide/cifs/usage.rst index c09674a75a9e..d989ae5778ba 100644 --- a/Documentation/admin-guide/cifs/usage.rst +++ b/Documentation/admin-guide/cifs/usage.rst @@ -270,6 +270,8 @@ configured for Unix Extensions (and the client has not disabled illegal Windows/NTFS/SMB characters to a remap range (this mount parameter is the default for SMB3). This remap (``mapposix``) range is also compatible with Mac (and "Services for Mac" on some older Windows). +When POSIX Extensions for SMB 3.1.1 are negotiated, remapping is automatically +disabled. CIFS VFS Mount Options ====================== diff --git a/fs/smb/client/connect.c b/fs/smb/client/connect.c index 28bc33496623..c4fb80b37738 100644 --- a/fs/smb/client/connect.c +++ b/fs/smb/client/connect.c @@ -3718,9 +3718,15 @@ int cifs_mount_get_tcon(struct cifs_mount_ctx *mnt_ctx) goto out; } - /* if new SMB3.11 POSIX extensions are supported do not remap / and \ */ - if (tcon->posix_extensions) + /* + * if new SMB3.11 POSIX extensions are supported, do not change anything in the + * path (i.e., do not remap / and \ and do not map any special characters) + */ + if (tcon->posix_extensions) { cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_POSIX_PATHS; + cifs_sb->mnt_cifs_flags &= ~(CIFS_MOUNT_MAP_SFM_CHR | + CIFS_MOUNT_MAP_SPECIAL_CHR); + } #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY /* tell server which Unix caps we support */ -- 2.50.1