cifs: clean up cifs_find_smb_ses (try #2)

This patch replaces the earlier patch by the same name. The only
difference is that MAX_PASSWORD_SIZE has been increased to attempt to
match the limits that windows enforces.

Do a better job of matching sessions by authtype. Matching by username
for a Kerberos session is incorrect, and anonymous sessions need special
handling.

Also, in the case where we do match by username, we also need to match
by password. That ensures that someone else doesn't "borrow" an existing
session without needing to know the password.

Finally, passwords can be longer than 16 bytes. Bump MAX_PASSWORD_SIZE
to 512 to match the size that the userspace mount helper allows.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 8fb1d10b8742bdf976bc5f9b7ad325ccfa33d4e7..7b91cb4f0da4e656f662c568293c2561cd5c8590 100644 (file)
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -37,7 +37,7 @@
 #define MAX_SHARE_SIZE  64     /* used to be 20, this should still be enough */
 #define MAX_USERNAME_SIZE 32   /* 32 is to allow for 15 char names + null
                                   termination then *2 for unicode versions */
-#define MAX_PASSWORD_SIZE 16
+#define MAX_PASSWORD_SIZE 512  /* max for windows seems to be 256 wide chars */
 
 #define CIFS_MIN_RCV_POOL 4
 

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index b24e4cea4e3c808288d3332a09e53efa18645f9f..b2063ce113ec9e14e973b4b4ea8d0ab863388bfe 100644 (file)
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -1644,17 +1644,27 @@ out_err:
 }
 
 static struct cifsSesInfo *
-cifs_find_smb_ses(struct TCP_Server_Info *server, char *username)
+cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb_vol *vol)
 {
-       struct list_head *tmp;
        struct cifsSesInfo *ses;
 
        write_lock(&cifs_tcp_ses_lock);
-       list_for_each(tmp, &server->smb_ses_list) {
-               ses = list_entry(tmp, struct cifsSesInfo, smb_ses_list);
-               if (strncmp(ses->userName, username, MAX_USERNAME_SIZE))
-                       continue;
-
+       list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
+               switch (server->secType) {
+               case Kerberos:
+                       if (vol->linux_uid != ses->linux_uid)
+                               continue;
+                       break;
+               default:
+                       /* anything else takes username/password */
+                       if (strncmp(ses->userName, vol->username,
+                                   MAX_USERNAME_SIZE))
+                               continue;
+                       if (strlen(vol->username) != 0 &&
+                           strncmp(ses->password, vol->password,
+                                   MAX_PASSWORD_SIZE))
+                               continue;
+               }
                ++ses->ses_count;
                write_unlock(&cifs_tcp_ses_lock);
                return ses;
@@ -1696,7 +1706,7 @@ cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb_vol *volume_info)
 
        xid = GetXid();
 
-       ses = cifs_find_smb_ses(server, volume_info->username);
+       ses = cifs_find_smb_ses(server, volume_info);
        if (ses) {
                cFYI(1, "Existing smb sess found (status=%d)", ses->status);