locking.c: Added fix for race condition in slow share mode code.

lsaparse.c: #ifdef'ed out code so this will compile - LUKE PLEASE CHECK THIS.
pipes.c: #ifdef'ed out code so this will compile - LUKE PLEASE CHECK THIS.
server.c: Fixed last known oplock race condition.
smb.h: Re-removed USE_OPLOCK defines - someone checked in an old version.
smbparse.c: #ifdef'ed out code so this will compile - LUKE PLEASE CHECK THIS.
Jeremy (jallison@whistle.com)

6 files changed, 93 insertions, 30 deletions

diff --git a/source/include/smb.h b/source/include/smb.h
index 3adb3e5a4cb..c347202743c 100644
--- a/source/include/smb.h
+++ b/source/include/smb.h
@@ -1042,10 +1042,8 @@ typedef struct
 {
   smb_shm_offset_t next_share_mode_entry;
   int pid;
-#ifdef USE_OPLOCKS
   uint16 op_port;
   uint16 op_type;
-#endif /* USE_OPLOCKS */
   int share_mode;
   struct timeval time;
 } share_mode_entry;
@@ -1054,10 +1052,8 @@ typedef struct
 typedef struct
 {
   int pid;
-#ifdef USE_OPLOCKS
   uint16 op_port;
   uint16 op_type;
-#endif /* USE_OPLOCKS */
   int share_mode;
   struct timeval time;
 } min_share_mode_entry;
@@ -1083,11 +1079,7 @@ struct connect_record
 };
 
 #ifndef LOCKING_VERSION
-#ifdef USE_OPLOCKS
 #define LOCKING_VERSION 4
-#else /* USE_OPLOCKS */
-#define LOCKING_VERSION 3
-#endif /* USE_OPLOCKS */
 #endif /* LOCKING_VERSION */
 
 #if !defined(FAST_SHARE_MODES)
@@ -1103,11 +1095,7 @@ struct connect_record
 #define SMF_FILENAME_LEN_OFFSET 8
 #define SMF_HEADER_LENGTH 10
 
-#ifdef USE_OPLOCKS
 #define SMF_ENTRY_LENGTH 20
-#else /* USE_OPLOCKS */
-#define SMF_ENTRY_LENGTH 16
-#endif /* USE_OPLOCKS */
 
 /*
  * Share mode record offsets.
@@ -1117,11 +1105,8 @@ struct connect_record
 #define SME_USEC_OFFSET 4
 #define SME_SHAREMODE_OFFSET 8
 #define SME_PID_OFFSET 12
-
-#ifdef USE_OPLOCKS
 #define SME_PORT_OFFSET 16
 #define SME_OPLOCK_TYPE_OFFSET 18
-#endif /* USE_OPLOCKS */
 
 #endif /* FAST_SHARE_MODES */
 
diff --git a/source/locking/locking.c b/source/locking/locking.c
index 6e321d0626e..639bc7be0ba 100644
--- a/source/locking/locking.c
+++ b/source/locking/locking.c
@@ -25,6 +25,10 @@
 
    May 1997. Jeremy Allison (jallison@whistle.com). Modified share mode
    locking to deal with multiple share modes per open file.
+
+   September 1997. Jeremy Allison (jallison@whistle.com). Added oplock
+   support.
+
 */
 
 #include "includes.h"
@@ -726,13 +730,60 @@ BOOL lock_share_entry(int cnum, uint32 dev, uint32 inode, share_lock_token *ptok
 
   {
     int old_umask;
+    BOOL gotlock = False;
     unbecome_user();
     old_umask = umask(0);
+
+    /*
+     * There was a race condition in the original slow share mode code.
+     * A smbd could open a share mode file, and before getting
+     * the lock, another smbd could delete the last entry for
+     * the share mode file and delete the file entry from the
+     * directory. Thus this smbd would be left with a locked
+     * share mode fd attached to a file that no longer had a
+     * directory entry. Thus another smbd would think that
+     * there were no outstanding opens on the file. To fix
+     * this we now check we can do a stat() call on the filename
+     * before allowing the lock to proceed, and back out completely
+     * and try the open again if we cannot.
+     * Jeremy Allison (jallison@whistle.com).
+     */
+
+    do
+    {
+      struct stat dummy_stat;
+
 #ifdef SECURE_SHARE_MODES
-    fd = (share_lock_token)open(fname,O_RDWR|O_CREAT,0600);
+      fd = (share_lock_token)open(fname,O_RDWR|O_CREAT,0600);
 #else /* SECURE_SHARE_MODES */
-    fd = (share_lock_token)open(fname,O_RDWR|O_CREAT,0666);
+      fd = (share_lock_token)open(fname,O_RDWR|O_CREAT,0666);
 #endif /* SECURE_SHARE_MODES */
+
+       /* At this point we have an open fd to the share mode file. 
+         Lock the first byte exclusively to signify a lock. */
+      if(fcntl_lock(fd, F_SETLKW, 0, 1, F_WRLCK) == False)
+      {
+        DEBUG(0,("ERROR lock_share_entry: fcntl_lock on file %s failed with %s\n",
+                  fname, strerror(errno)));   
+        close(fd);
+        return False;
+      }
+
+      /* 
+       * If we cannot stat the filename, the file was deleted between
+       * the open and the lock call. Back out and try again.
+       */
+
+      if(stat(fname, &dummy_stat)!=0)
+      {
+        DEBUG(2,("lock_share_entry: Re-issuing open on %s to fix race. Error was %s\n",
+                fname, strerror(errno)));
+        close(fd);
+      }
+      else
+        gotlock = True;
+    } while(!gotlock);
+
     umask(old_umask);
     if(!become_user(cnum,Connections[cnum].vuid))
     {
@@ -750,18 +801,8 @@ BOOL lock_share_entry(int cnum, uint32 dev, uint32 inode, share_lock_token *ptok
     }
   }
 
-  /* At this point we have an open fd to the share mode file. 
-     Lock the first byte exclusively to signify a lock. */
-  if(fcntl_lock(fd, F_SETLKW, 0, 1, F_WRLCK) == False)
-   {
-      DEBUG(0,("ERROR lock_share_entry: fcntl_lock failed with %s\n",
-                  strerror(errno)));   
-      close(fd);
-      return False;
-   }
-
-   *ptok = (share_lock_token)fd;
-   return True;
+  *ptok = (share_lock_token)fd;
+  return True;
 }
 
 /*******************************************************************
@@ -781,7 +822,7 @@ BOOL unlock_share_entry(int cnum, uint32 dev, uint32 inode, share_lock_token tok
       ret = False;
    }
  
-  close((int)token);
+  close(fd);
   return ret;
 }
 
diff --git a/source/lsaparse.c b/source/lsaparse.c
index 2113b19cd33..b1d9d739240 100644
--- a/source/lsaparse.c
+++ b/source/lsaparse.c
@@ -24,6 +24,7 @@
 extern int DEBUGLEVEL;
 
 
+#if 0 /* NEED TO DO THIS TO GET A COMPILE - LUKE PLEASE CHECK THIS !!! */
 /*******************************************************************
 reads or writes an LSA_R_OPEN_POL structure.
 ********************************************************************/
@@ -446,6 +447,7 @@ char* lsa_io_r_sam_logoff(BOOL io, LSA_R_SAM_LOGOFF *r_l, char *q, char *base, i
 	return q;
 }
 
+#endif /* 0 LUKE PLEASE CHECK !! */
 #if 0
 /*******************************************************************
 reads or writes a structure.
diff --git a/source/smbd/pipes.c b/source/smbd/pipes.c
index 95b69ef4d97..ffa64a4e808 100644
--- a/source/smbd/pipes.c
+++ b/source/smbd/pipes.c
@@ -364,6 +364,8 @@ BOOL api_LsarpcTNP(int cnum,int uid, char *param,char *data,
   return(True);
 }
 
+#if 0 /* HAVING TO DO THIS TO GET THINGS TO COMPILE - LUKE PLEASE CHECK THIS !!! */
+
 /*
    PAXX: Someone fix above.
    The above API is indexing RPC calls based on RPC flags and 
@@ -757,3 +759,5 @@ static int lsa_reply_sam_logoff(LSA_Q_SAM_LOGOFF *q_s, char *q, char *base,
 	/* return length of SMB data stored */
 	return q - start; 
 }
+
+#endif /* LUKE PLEASE CHECK THIS !! */
diff --git a/source/smbd/server.c b/source/smbd/server.c
index 4f5b01ba91e..92c219c71b3 100644
--- a/source/smbd/server.c
+++ b/source/smbd/server.c
@@ -2455,6 +2455,9 @@ address %x. Error was %s\n", htonl(INADDR_LOOPBACK), strerror(errno)));
   }
   oplock_port = ntohs(sock_name.sin_port);
 
+  DEBUG(3,("open_oplock ipc: pid = %d, oplock_port = %u\n", 
+            getpid(), oplock_port));
+
   return True;
 }
 
@@ -2545,6 +2548,31 @@ pid %d, port %d, for file dev = %x, inode = %x\n", remotepid,
 
       }
       break;
+    /* 
+     * Keep this as a debug case - eventually we can remove it.
+     */
+    case 0x8001:
+      DEBUG(0,("process_local_message: Received unsolicited break \
+reply - dumping info.\n"));
+
+      if(msg_len != OPLOCK_BREAK_MSG_LEN)
+      {
+        DEBUG(0,("process_local_message: ubr: incorrect length for reply \
+(was %d, should be %d).\n", msg_len, OPLOCK_BREAK_MSG_LEN));
+        return False;
+      }
+
+      {
+        uint32 remotepid = IVAL(msg_start,OPLOCK_BREAK_PID_OFFSET);
+        uint32 dev = IVAL(msg_start,OPLOCK_BREAK_DEV_OFFSET);
+        uint32 inode = IVAL(msg_start, OPLOCK_BREAK_INODE_OFFSET);
+
+        DEBUG(0,("process_local_message: unsolicited oplock break reply from \
+pid %d, port %d, dev = %x, inode = %x\n", remotepid, from_port, dev, inode));
+
+       }
+       return False;
+
     default:
       DEBUG(0,("process_local_message: unknown UDP message command code (%x) - ignoring.\n",
                 (unsigned int)SVAL(msg_start,0)));
@@ -2860,6 +2888,7 @@ oplock break response from pid %d on port %d for dev = %x, inode = %x.\n",
              share_entry->pid, share_entry->op_port, dev, inode));
       if(push_local_message(op_break_reply, sizeof(op_break_reply)) == False)
         return False;
+      continue;
     }
 
     break;
diff --git a/source/smbparse.c b/source/smbparse.c
index 7ea140f7cb7..ae1f4f4b253 100644
--- a/source/smbparse.c
+++ b/source/smbparse.c
@@ -456,7 +456,9 @@ char* smb_io_dom_query(BOOL io, DOM_QUERY *d_q, char *q, char *base, int align)
 
 	if (d_q->buffer_dom_name != 0)
 	{
+#if 0 /* REMOVED AS WON'T COMPILE AS IS - LUKE PLEASE CHECK !!!!! */
 		q = smb_io_unistr(io, &(d_q->uni_domain_name), q, base, align); /* domain name (unicode string) */
+#endif
 	}
 	if (d_q->buffer_dom_sid != 0)
 	{