[CIFS] When mandatory encryption on share, fail mount
When mandatory encryption is configured in samba server on a
share (smb.conf parameter "smb encrypt = mandatory") the
server will hang up the tcp session when we try to send
the first frame after the tree connect if it is not a
QueryFSUnixInfo, this causes cifs mount to hang (it must
be killed with ctl-c). Move the QueryFSUnixInfo call
earlier in the mount sequence, and check whether the SetFSUnixInfo
fails due to mandatory encryption so we can return a sensible
error (EACCES) on mount.
In a future patch (for 2.6.40) we will support mandatory
encryption.
CC: Stable <stable@kernel.org>
Reviewed-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 2e7a79c..581654f 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -2530,7 +2530,7 @@
if (!CIFSSMBQFSUnixInfo(xid, tcon)) {
__u64 cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
-
+ cFYI(1, "unix caps which server supports %lld", cap);
/* check for reconnect case in which we do not
want to change the mount behavior if we can avoid it */
if (vol_info == NULL) {
@@ -2548,6 +2548,9 @@
}
}
+ if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
+ cERROR(1, "per-share encryption not supported yet");
+
cap &= CIFS_UNIX_CAP_MASK;
if (vol_info && vol_info->no_psx_acl)
cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
@@ -2596,6 +2599,10 @@
cFYI(1, "very large read cap");
if (cap & CIFS_UNIX_LARGE_WRITE_CAP)
cFYI(1, "very large write cap");
+ if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_CAP)
+ cFYI(1, "transport encryption cap");
+ if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
+ cFYI(1, "mandatory transport encryption cap");
#endif /* CIFS_DEBUG2 */
if (CIFSSMBSetFSUnixInfo(xid, tcon, cap)) {
if (vol_info == NULL) {
@@ -3022,20 +3029,26 @@
goto remote_path_check;
}
+ /* tell server which Unix caps we support */
+ if (tcon->ses->capabilities & CAP_UNIX) {
+ /* reset of caps checks mount to see if unix extensions
+ disabled for just this mount */
+ reset_cifs_unix_caps(xid, tcon, sb, volume_info);
+ if ((tcon->ses->server->tcpStatus == CifsNeedReconnect) &&
+ (le64_to_cpu(tcon->fsUnixInfo.Capability) &
+ CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)) {
+ rc = -EACCES;
+ goto mount_fail_check;
+ }
+ } else
+ tcon->unix_ext = 0; /* server does not support them */
+
/* do not care if following two calls succeed - informational */
if (!tcon->ipc) {
CIFSSMBQFSDeviceInfo(xid, tcon);
CIFSSMBQFSAttributeInfo(xid, tcon);
}
- /* tell server which Unix caps we support */
- if (tcon->ses->capabilities & CAP_UNIX)
- /* reset of caps checks mount to see if unix extensions
- disabled for just this mount */
- reset_cifs_unix_caps(xid, tcon, sb, volume_info);
- else
- tcon->unix_ext = 0; /* server does not support them */
-
/* convert forward to back slashes in prepath here if needed */
if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS) == 0)
convert_delimiter(cifs_sb->prepath, CIFS_DIR_SEP(cifs_sb));