ksmbd-tools: don't add global default `read only = yes'

Since share parameters are applied in the non-descript hash table
iteration order, a share parameter should never undo the effect of an
another. For example, `force user' checks `share->force_gid' such that
it doesn't undo `force group' applied earlier. However, `read only'
does not follow this convention since it may undo `writeable' (and so
may its aliases). Since the hash table iteration order is non-descript,
this means that a share with `read only = yes' and `writeable = yes'
may or may not allow read-write access. With the 3.5.0 release, due to
the default global `read only = yes' added in commit 54d2a02, this
effect is always in play for shares that give `writeable = yes' (or
its aliases) instead of `read only = no'. Fix this by not adding
global default `read only = yes'.

Note that not setting `KSMBD_SHARE_FLAG_READONLY' for initial shares is
fine as it is only used to set `KSMBD_TREE_CONN_FLAG_READ_ONLY' which
itself is unused (and was broken until commit 3f88fbe).

Note also that the use of the IPC$ share is guarded by checking for
`KSMBD_SHARE_FLAG_PIPE'. So if it's given `KSMBD_SHARE_FLAG_WRITEABLE'
through the global section or a user-defined section, the code paths
for its use should not change.

Signed-off-by: Atte Heikkilä <[email protected]>
Signed-off-by: Namjae Jeon <[email protected]>

ksmbd.conf.5.in

@@ -224,7 +224,7 @@ Default: \fBread list = \fR
 Users are allowed read-only access to the share.
 With \fBread only = no\fR, the effect is the same as with \fBwriteable = yes\fR.
 
-Default: \fBread only = yes\fR
+Default: \fBread only = ; yes\fR
 .TP
 \fBrestrict anonymous\fR (G)
 How to restrict connections to any share as the user given with \fBguest account\fR.
@@ -353,7 +353,7 @@ Default: \fBworkgroup = WORKGROUP\fR
 Users are allowed read-write access to the share.
 With \fBwritable = yes\fR, the effect is the same as with \fBread only = no\fR.
 
-Default: \fBwritable = no\fR
+Default: \fBwritable = \fR
 .TP
 \fBwriteable\fR (S)
 Synonym for \fBwritable\fP.

ksmbd.conf.example

@@ -49,7 +49,7 @@
 	oplocks = yes
 	path = 
 	read list = 
-	read only = yes
+	read only = ; yes
 	store dos attributes = yes
 	valid users = 
 	veto files = 

tools/config_parser.c

@@ -564,7 +564,6 @@ static void add_group_ipc_share_conf(void)
 {
 	add_group_key_value("comment = IPC share");
 	add_group_key_value("guest ok = yes");
-	add_group_key_value("read only = yes");
 }
 
 static int finalize_smbconf_parser(void)

tools/management/share.c

@@ -73,7 +73,7 @@ const char *KSMBD_SHARE_DEFCONF[KSMBD_SHARE_CONF_MAX] = {
 	"",
 	"no",
 	"",
-	"yes",
+	"; yes",
 /*5*/	"yes",
 	"",
 	"",