Fedora kernel-2.6.17-1.2142_FC4 patched with stable patch-2.6.17.4-vs2.0.2-rc26.diff
[linux-2.6.git] / fs / cifs / misc.c
index 072b4ee..fafd056 100644 (file)
@@ -1,7 +1,7 @@
 /*
  *   fs/cifs/misc.c
  *
- *   Copyright (C) International Business Machines  Corp., 2002,2004
+ *   Copyright (C) International Business Machines  Corp., 2002,2005
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
  *   This library is free software; you can redistribute it and/or modify
@@ -34,8 +34,6 @@ extern mempool_t *cifs_sm_req_poolp;
 extern mempool_t *cifs_req_poolp;
 extern struct task_struct * oplockThread;
 
-static __u16 GlobalMid;                /* multiplex id - rotating counter */
-
 /* The xid serves as a useful identifier for each incoming vfs request, 
    in a similar way to the mid which is useful to track each sent smb, 
    and CurrentXid can also provide a running counter (although it 
@@ -51,6 +49,8 @@ _GetXid(void)
        GlobalTotalActiveXid++;
        if (GlobalTotalActiveXid > GlobalMaxActiveXid)
                GlobalMaxActiveXid = GlobalTotalActiveXid;      /* keep high water mark for number of simultaneous vfs ops in our filesystem */
+       if(GlobalTotalActiveXid > 65000)
+               cFYI(1,("warning: more than 65000 requests active"));
        xid = GlobalCurrentXid++;
        spin_unlock(&GlobalMid_Lock);
        return xid;
@@ -72,10 +72,9 @@ sesInfoAlloc(void)
        struct cifsSesInfo *ret_buf;
 
        ret_buf =
-           (struct cifsSesInfo *) kmalloc(sizeof (struct cifsSesInfo),
+           (struct cifsSesInfo *) kzalloc(sizeof (struct cifsSesInfo),
                                           GFP_KERNEL);
        if (ret_buf) {
-               memset(ret_buf, 0, sizeof (struct cifsSesInfo));
                write_lock(&GlobalSMBSeslock);
                atomic_inc(&sesInfoAllocCount);
                ret_buf->status = CifsNew;
@@ -98,14 +97,10 @@ sesInfoFree(struct cifsSesInfo *buf_to_free)
        atomic_dec(&sesInfoAllocCount);
        list_del(&buf_to_free->cifsSessionList);
        write_unlock(&GlobalSMBSeslock);
-       if (buf_to_free->serverOS)
-               kfree(buf_to_free->serverOS);
-       if (buf_to_free->serverDomain)
-               kfree(buf_to_free->serverDomain);
-       if (buf_to_free->serverNOS)
-               kfree(buf_to_free->serverNOS);
-       if (buf_to_free->password)
-               kfree(buf_to_free->password);
+       kfree(buf_to_free->serverOS);
+       kfree(buf_to_free->serverDomain);
+       kfree(buf_to_free->serverNOS);
+       kfree(buf_to_free->password);
        kfree(buf_to_free);
 }
 
@@ -114,10 +109,9 @@ tconInfoAlloc(void)
 {
        struct cifsTconInfo *ret_buf;
        ret_buf =
-           (struct cifsTconInfo *) kmalloc(sizeof (struct cifsTconInfo),
+           (struct cifsTconInfo *) kzalloc(sizeof (struct cifsTconInfo),
                                            GFP_KERNEL);
        if (ret_buf) {
-               memset(ret_buf, 0, sizeof (struct cifsTconInfo));
                write_lock(&GlobalSMBSeslock);
                atomic_inc(&tconInfoAllocCount);
                list_add(&ret_buf->cifsConnectionList,
@@ -144,8 +138,7 @@ tconInfoFree(struct cifsTconInfo *buf_to_free)
        atomic_dec(&tconInfoAllocCount);
        list_del(&buf_to_free->cifsConnectionList);
        write_unlock(&GlobalSMBSeslock);
-       if (buf_to_free->nativeFileSystem)
-               kfree(buf_to_free->nativeFileSystem);
+       kfree(buf_to_free->nativeFileSystem);
        kfree(buf_to_free);
 }
 
@@ -166,6 +159,9 @@ cifs_buf_get(void)
        if (ret_buf) {
                memset(ret_buf, 0, sizeof(struct smb_hdr) + 3);
                atomic_inc(&bufAllocCount);
+#ifdef CONFIG_CIFS_STATS2
+               atomic_inc(&totBufAllocCount);
+#endif /* CONFIG_CIFS_STATS2 */
        }
 
        return ret_buf;
@@ -200,6 +196,10 @@ cifs_small_buf_get(void)
        /* No need to clear memory here, cleared in header assemble */
        /*      memset(ret_buf, 0, sizeof(struct smb_hdr) + 27);*/
                atomic_inc(&smBufAllocCount);
+#ifdef CONFIG_CIFS_STATS2
+               atomic_inc(&totSmBufAllocCount);
+#endif /* CONFIG_CIFS_STATS2 */
+
        }
        return ret_buf;
 }
@@ -218,6 +218,76 @@ cifs_small_buf_release(void *buf_to_free)
        return;
 }
 
+/* 
+       Find a free multiplex id (SMB mid). Otherwise there could be
+       mid collisions which might cause problems, demultiplexing the
+       wrong response to this request. Multiplex ids could collide if
+       one of a series requests takes much longer than the others, or
+       if a very large number of long lived requests (byte range
+       locks or FindNotify requests) are pending.  No more than
+       64K-1 requests can be outstanding at one time.  If no 
+       mids are available, return zero.  A future optimization
+       could make the combination of mids and uid the key we use
+       to demultiplex on (rather than mid alone).  
+       In addition to the above check, the cifs demultiplex
+       code already used the command code as a secondary
+       check of the frame and if signing is negotiated the
+       response would be discarded if the mid were the same
+       but the signature was wrong.  Since the mid is not put in the
+       pending queue until later (when it is about to be dispatched)
+       we do have to limit the number of outstanding requests 
+       to somewhat less than 64K-1 although it is hard to imagine
+       so many threads being in the vfs at one time.
+*/
+__u16 GetNextMid(struct TCP_Server_Info *server)
+{
+       __u16 mid = 0;
+       __u16 last_mid;
+       int   collision;  
+
+       if(server == NULL)
+               return mid;
+
+       spin_lock(&GlobalMid_Lock);
+       last_mid = server->CurrentMid; /* we do not want to loop forever */
+       server->CurrentMid++;
+       /* This nested loop looks more expensive than it is.
+       In practice the list of pending requests is short, 
+       fewer than 50, and the mids are likely to be unique
+       on the first pass through the loop unless some request
+       takes longer than the 64 thousand requests before it
+       (and it would also have to have been a request that
+        did not time out) */
+       while(server->CurrentMid != last_mid) {
+               struct list_head *tmp;
+               struct mid_q_entry *mid_entry;
+
+               collision = 0;
+               if(server->CurrentMid == 0)
+                       server->CurrentMid++;
+
+               list_for_each(tmp, &server->pending_mid_q) {
+                       mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
+
+                       if ((mid_entry->mid == server->CurrentMid) &&
+                           (mid_entry->midState == MID_REQUEST_SUBMITTED)) {
+                               /* This mid is in use, try a different one */
+                               collision = 1;
+                               break;
+                       }
+               }
+               if(collision == 0) {
+                       mid = server->CurrentMid;
+                       break;
+               }
+               server->CurrentMid++;
+       }
+       spin_unlock(&GlobalMid_Lock);
+       return mid;
+}
+
+/* NB: MID can not be set if treeCon not passed in, in that
+   case it is responsbility of caller to set the mid */
 void
 header_assemble(struct smb_hdr *buffer, char smb_command /* command */ ,
                const struct cifsTconInfo *treeCon, int word_count
@@ -227,13 +297,14 @@ header_assemble(struct smb_hdr *buffer, char smb_command /* command */ ,
        struct cifsSesInfo * ses;
        char *temp = (char *) buffer;
 
-       memset(temp,0,MAX_CIFS_HDR_SIZE);
+       memset(temp,0,256); /* bigger than MAX_CIFS_HDR_SIZE */
 
        buffer->smb_buf_length =
            (2 * word_count) + sizeof (struct smb_hdr) -
            4 /*  RFC 1001 length field does not count */  +
            2 /* for bcc field itself */ ;
-       /* Note that this is the only network field that has to be converted to big endian and it is done just before we send it */
+       /* Note that this is the only network field that has to be converted
+          to big endian and it is done just before we send it */
 
        buffer->Protocol[0] = 0xFF;
        buffer->Protocol[1] = 'S';
@@ -245,8 +316,6 @@ header_assemble(struct smb_hdr *buffer, char smb_command /* command */ ,
        buffer->Pid = cpu_to_le16((__u16)current->tgid);
        buffer->PidHigh = cpu_to_le16((__u16)(current->tgid >> 16));
        spin_lock(&GlobalMid_Lock);
-       GlobalMid++;
-       buffer->Mid = GlobalMid;
        spin_unlock(&GlobalMid_Lock);
        if (treeCon) {
                buffer->Tid = treeCon->tid;
@@ -256,8 +325,9 @@ header_assemble(struct smb_hdr *buffer, char smb_command /* command */ ,
                        if (treeCon->ses->capabilities & CAP_STATUS32) {
                                buffer->Flags2 |= SMBFLG2_ERR_STATUS;
                        }
-
-                       buffer->Uid = treeCon->ses->Suid;       /* always in LE format */
+                       /* Uid is not converted */
+                       buffer->Uid = treeCon->ses->Suid;
+                       buffer->Mid = GetNextMid(treeCon->ses->server);
                        if(multiuser_mount != 0) {
                /* For the multiuser case, there are few obvious technically  */
                /* possible mechanisms to match the local linux user (uid)    */
@@ -283,12 +353,12 @@ header_assemble(struct smb_hdr *buffer, char smb_command /* command */ ,
                /*  BB Add support for establishing new tCon and SMB Session  */
                /*      with userid/password pairs found on the smb session   */ 
                /*      for other target tcp/ip addresses               BB    */
-                               if(current->uid != treeCon->ses->linux_uid) {
-                                       cFYI(1,("Multiuser mode and UID did not match tcon uid "));
+                               if(current->fsuid != treeCon->ses->linux_uid) {
+                                       cFYI(1,("Multiuser mode and UID did not match tcon uid"));
                                        read_lock(&GlobalSMBSeslock);
                                        list_for_each(temp_item, &GlobalSMBSessionList) {
                                                ses = list_entry(temp_item, struct cifsSesInfo, cifsSessionList);
-                                               if(ses->linux_uid == current->uid) {
+                                               if(ses->linux_uid == current->fsuid) {
                                                        if(ses->server == treeCon->ses->server) {
                                                                cFYI(1,("found matching uid substitute right smb_uid"));  
                                                                buffer->Uid = ses->Suid;
@@ -305,6 +375,8 @@ header_assemble(struct smb_hdr *buffer, char smb_command /* command */ ,
                }
                if (treeCon->Flags & SMB_SHARE_IS_IN_DFS)
                        buffer->Flags2 |= SMBFLG2_DFS;
+               if (treeCon->nocase)
+                       buffer->Flags  |= SMBFLG_CASELESS;
                if((treeCon->ses) && (treeCon->ses->server))
                        if(treeCon->ses->server->secMode & 
                          (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
@@ -330,12 +402,12 @@ checkSMBhdr(struct smb_hdr *smb, __u16 mid)
                        if(smb->Command == SMB_COM_LOCKING_ANDX)
                                return 0;
                        else
-                               cERROR(1, ("Rcvd Request not response "));         
+                               cERROR(1, ("Rcvd Request not response"));         
                }
        } else { /* bad signature or mid */
                if (*(__le32 *) smb->Protocol != cpu_to_le32(0x424d53ff))
                        cERROR(1,
-                              ("Bad protocol string signature header %x ",
+                              ("Bad protocol string signature header %x",
                                *(unsigned int *) smb->Protocol));
                if (mid != smb->Mid)
                        cERROR(1, ("Mids do not match"));
@@ -347,10 +419,9 @@ checkSMBhdr(struct smb_hdr *smb, __u16 mid)
 int
 checkSMB(struct smb_hdr *smb, __u16 mid, int length)
 {
-       __u32 len = be32_to_cpu(smb->smb_buf_length);
-       cFYI(0,
-            ("Entering checkSMB with Length: %x, smb_buf_length: %x ",
-             length, len));
+       __u32 len = smb->smb_buf_length;
+       __u32 clc_len;  /* calculated length */
+       cFYI(0, ("checkSMB Length: 0x%x, smb_buf_length: 0x%x", length, len));
        if (((unsigned int)length < 2 + sizeof (struct smb_hdr)) ||
            (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4)) {
                if ((unsigned int)length < 2 + sizeof (struct smb_hdr)) {
@@ -358,36 +429,59 @@ checkSMB(struct smb_hdr *smb, __u16 mid, int length)
                                sizeof (struct smb_hdr) - 1)
                            && (smb->Status.CifsError != 0)) {
                                smb->WordCount = 0;
-                               return 0;       /* some error cases do not return wct and bcc */
+                               /* some error cases do not return wct and bcc */
+                               return 0;
                        } else {
                                cERROR(1, ("Length less than smb header size"));
                        }
-
                }
                if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4)
-                       cERROR(1,
-                              ("smb_buf_length greater than MaxBufSize"));
-               cERROR(1,
-                      ("bad smb detected. Illegal length. The mid=%d",
-                       smb->Mid));
+                       cERROR(1, ("smb length greater than MaxBufSize, mid=%d",
+                                  smb->Mid));
                return 1;
        }
 
        if (checkSMBhdr(smb, mid))
                return 1;
+       clc_len = smbCalcSize_LE(smb);
 
-       if ((4 + len != smbCalcSize(smb))
-           || (4 + len != (unsigned int)length)) {
-               return 0;
-       } else {
-               cERROR(1, ("smbCalcSize %x ", smbCalcSize(smb)));
-               cERROR(1,
-                      ("bad smb size detected. The Mid=%d", smb->Mid));
+       if(4 + len != (unsigned int)length) {
+               cERROR(1, ("Length read does not match RFC1001 length %d",len));
                return 1;
        }
+
+       if (4 + len != clc_len) {
+               /* check if bcc wrapped around for large read responses */
+               if((len > 64 * 1024) && (len > clc_len)) {
+                       /* check if lengths match mod 64K */
+                       if(((4 + len) & 0xFFFF) == (clc_len & 0xFFFF))
+                               return 0; /* bcc wrapped */                     
+               }
+               cFYI(1, ("Calculated size %d vs length %d mismatch for mid %d",
+                               clc_len, 4 + len, smb->Mid));
+               /* Windows XP can return a few bytes too much, presumably
+               an illegal pad, at the end of byte range lock responses 
+               so we allow for that three byte pad, as long as actual
+               received length is as long or longer than calculated length */
+               /* We have now had to extend this more, since there is a 
+               case in which it needs to be bigger still to handle a
+               malformed response to transact2 findfirst from WinXP when
+               access denied is returned and thus bcc and wct are zero
+               but server says length is 0x21 bytes too long as if the server
+               forget to reset the smb rfc1001 length when it reset the
+               wct and bcc to minimum size and drop the t2 parms and data */
+               if((4+len > clc_len) && (len <= clc_len + 512))
+                       return 0;
+               else {
+                       cERROR(1, ("RFC1001 size %d bigger than SMB for Mid=%d",
+                                       len, smb->Mid));
+                       return 1;
+               }
+       }
+       return 0;
 }
 int
-is_valid_oplock_break(struct smb_hdr *buf)
+is_valid_oplock_break(struct smb_hdr *buf, struct TCP_Server_Info *srv)
 {    
        struct smb_com_lock_req * pSMB = (struct smb_com_lock_req *)buf;
        struct list_head *tmp;
@@ -447,10 +541,8 @@ is_valid_oplock_break(struct smb_hdr *buf)
        read_lock(&GlobalSMBSeslock);
        list_for_each(tmp, &GlobalTreeConnectionList) {
                tcon = list_entry(tmp, struct cifsTconInfo, cifsConnectionList);
-               if (tcon->tid == buf->Tid) {
-#ifdef CONFIG_CIFS_STATS
-                       atomic_inc(&tcon->num_oplock_brks);
-#endif
+               if ((tcon->tid == buf->Tid) && (srv == tcon->ses->server)) {
+                       cifs_stats_inc(&tcon->num_oplock_brks);
                        list_for_each(tmp1,&tcon->openFileList){
                                netfile = list_entry(tmp1,struct cifsFileInfo,
                                                     tlist);
@@ -603,14 +695,16 @@ cifsConvertToUCS(__le16 * target, const char *source, int maxlen,
        int i,j,charlen;
        int len_remaining = maxlen;
        char src_char;
+       __u16 temp;
 
        if(!mapChars) 
-               return cifs_strtoUCS((wchar_t *) target, source, PATH_MAX, cp);
+               return cifs_strtoUCS(target, source, PATH_MAX, cp);
 
        for(i = 0, j = 0; i < maxlen; j++) {
                src_char = source[i];
                switch (src_char) {
                        case 0:
+                               target[j] = 0;
                                goto ctoUCS_out;
                        case ':':
                                target[j] = cpu_to_le16(UNI_COLON);
@@ -638,13 +732,14 @@ cifsConvertToUCS(__le16 * target, const char *source, int maxlen,
                                break;*/
                        default:
                                charlen = cp->char2uni(source+i,
-                                       len_remaining, target+j);
+                                       len_remaining, &temp);
                                /* if no match, use question mark, which
                                at least in some cases servers as wild card */
                                if(charlen < 1) {
                                        target[j] = cpu_to_le16(0x003f);
                                        charlen = 1;
-                               }
+                               } else
+                                       target[j] = cpu_to_le16(temp);
                                len_remaining -= charlen;
                                /* character may take more than one byte in the
                                   the source string, but will take exactly two