[CIFS] Allow disabling CIFS Unix Extensions as mount option

Previously the only way to do this was to umount all mounts to that server,
turn off a proc setting (/proc/fs/cifs/LinuxExtensionsEnabled).

Fixes Samba bugzilla bug number: 4582 (and also 2008)

Signed-off-by: Steve French <sfrench@us.ibm.com>

diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index a0a2f31..1cebb7e 100644 (file)
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -316,10 +316,10 @@ cifs_show_options(struct seq_file *s, struct vfsmount *m)
                if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS)
                        seq_printf(s, ",posixpaths");
                if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_UID) ||
-                  !(cifs_sb->tcon->ses->capabilities & CAP_UNIX))
+                  !(cifs_sb->tcon->unix_ext))
                        seq_printf(s, ",uid=%d", cifs_sb->mnt_uid);
                if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_GID) ||
-                  !(cifs_sb->tcon->ses->capabilities & CAP_UNIX))
+                  !(cifs_sb->tcon->unix_ext))
                        seq_printf(s, ",gid=%d", cifs_sb->mnt_gid);
                seq_printf(s, ",rsize=%d", cifs_sb->rsize);
                seq_printf(s, ",wsize=%d", cifs_sb->wsize);

diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 0a78131..b98742f 100644 (file)
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -281,7 +281,9 @@ struct cifsTconInfo {
        FILE_SYSTEM_UNIX_INFO fsUnixInfo;
        unsigned retry:1;
        unsigned nocase:1;
-       /* BB add field for back pointer to sb struct? */
+       unsigned unix_ext:1; /* if off disable Linux extensions to CIFS protocol
+                               for this mount even if server would support */
+       /* BB add field for back pointer to sb struct(s)? */
 };
 
 /*

diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index a6ff406..8eb102f 100644 (file)
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -132,10 +132,10 @@ small_smb_init(int smb_command, int wct, struct cifsTconInfo *tcon,
                                /* Give Demultiplex thread up to 10 seconds to
                                   reconnect, should be greater than cifs socket
                                   timeout which is 7 seconds */
-                       while(tcon->ses->server->tcpStatus ==
+                       while (tcon->ses->server->tcpStatus ==
                                                         CifsNeedReconnect) {
                                wait_event_interruptible_timeout(tcon->ses->server->response_q,
-                                       (tcon->ses->server->tcpStatus == 
+                                       (tcon->ses->server->tcpStatus ==
                                                        CifsGood), 10 * HZ);
                                if (tcon->ses->server->tcpStatus ==
                                                        CifsNeedReconnect) {
@@ -213,7 +213,7 @@ small_smb_init(int smb_command, int wct, struct cifsTconInfo *tcon,
        }
 
        header_assemble((struct smb_hdr *) *request_buf, smb_command,
-                       tcon,wct);
+                       tcon, wct);
 
        if (tcon != NULL)
                cifs_stats_inc(&tcon->num_smbs_sent);
@@ -387,7 +387,7 @@ static int validate_t2(struct smb_t2_rsp *pSMB)
                        /* check that bcc is less than negotiated smb buffer */
                        total_size = le16_to_cpu(pSMB->t2_rsp.ParameterCount);
                        if (total_size < 512) {
-                               total_size += 
+                               total_size +=
                                        le16_to_cpu(pSMB->t2_rsp.DataCount);
                                /* BCC le converted in SendReceive */
                                pBCC = (pSMB->hdr.WordCount * 2) +
@@ -2758,7 +2758,7 @@ static __u16 ACL_to_cifs_posix(char *parm_data, const char *pACL,
                return 0;
 
        count = posix_acl_xattr_count((size_t)buflen);
-       cFYI(1,("setting acl with %d entries from buf of length %d and "
+       cFYI(1, ("setting acl with %d entries from buf of length %d and "
                "version of %d",
                count, buflen, le32_to_cpu(local_acl->a_version)));
        if (le32_to_cpu(local_acl->a_version) != 2) {
@@ -3638,15 +3638,6 @@ int CIFSFindNext(const int xid, struct cifsTconInfo *tcon,
        pSMB->SearchHandle = searchHandle;      /* always kept as le */
        pSMB->SearchCount =
                cpu_to_le16(CIFSMaxBufSize / sizeof (FILE_UNIX_INFO));
-       /* test for Unix extensions */
-/*     if (tcon->ses->capabilities & CAP_UNIX) {
-               pSMB->InformationLevel = cpu_to_le16(SMB_FIND_FILE_UNIX);
-               psrch_inf->info_level = SMB_FIND_FILE_UNIX;
-       } else {
-               pSMB->InformationLevel =
-                  cpu_to_le16(SMB_FIND_FILE_DIRECTORY_INFO);
-               psrch_inf->info_level = SMB_FIND_FILE_DIRECTORY_INFO;
-       } */
        pSMB->InformationLevel = cpu_to_le16(psrch_inf->info_level);
        pSMB->ResumeKey = psrch_inf->resume_key;
        pSMB->SearchFlags =
@@ -3966,7 +3957,7 @@ getDFSRetry:
                                        (8 /* sizeof start of data block */ +
                                        data_offset +
                                        (char *) &pSMBr->hdr.Protocol);
-                       cFYI(1,("num_referrals: %d dfs flags: 0x%x ... \n"
+                       cFYI(1, ("num_referrals: %d dfs flags: 0x%x ... \n"
                                "for referral one refer size: 0x%x srv "
                                "type: 0x%x refer flags: 0x%x ttl: 0x%x",
                                le16_to_cpu(pSMBr->NumberOfReferrals),

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 8b341a8..e93da7a 100644 (file)
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -85,6 +85,7 @@ struct smb_vol {
        unsigned direct_io:1;
        unsigned remap:1;   /* set to remap seven reserved chars in filenames */
        unsigned posix_paths:1;   /* unset to not ask for posix pathnames. */
+       unsigned no_linux_ext:1;
        unsigned sfu_emul:1;
        unsigned nullauth:1; /* attempt to authenticate with null user */
        unsigned nocase;     /* request case insensitive filenames */
@@ -1192,6 +1193,10 @@ cifs_parse_mount_options(char *options, const char *devname,
                        vol->posix_paths = 1;
                } else if (strnicmp(data, "noposixpaths", 12) == 0) {
                        vol->posix_paths = 0;
+               } else if (strnicmp(data, "nounix", 6) == 0) {
+                       vol->no_linux_ext = 1;
+               } else if (strnicmp(data, "nolinux", 7) == 0) {
+                       vol->no_linux_ext = 1;
                } else if ((strnicmp(data, "nocase", 6) == 0) ||
                           (strnicmp(data, "ignorecase", 10)  == 0)) {
                        vol->nocase = 1;
@@ -1665,6 +1670,18 @@ void reset_cifs_unix_caps(int xid, struct cifsTconInfo *tcon,
         * and once without posixacls or posix paths? */
        __u64 saved_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
 
+       if (vol_info && vol_info->no_linux_ext) {
+               tcon->fsUnixInfo.Capability = 0;
+               tcon->unix_ext = 0; /* Unix Extensions disabled */
+               cFYI(1, ("Linux protocol extensions disabled"));
+               return;
+       } else if (vol_info)
+               tcon->unix_ext = 1; /* Unix Extensions supported */
+
+       if (tcon->unix_ext == 0) {
+               cFYI(1, ("Unix extensions disabled so not set on reconnect"));
+               return;
+       }
 
        if (!CIFSSMBQFSUnixInfo(xid, tcon)) {
                __u64 cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
@@ -1678,10 +1695,6 @@ void reset_cifs_unix_caps(int xid, struct cifsTconInfo *tcon,
                                cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
                        if ((saved_cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0)
                                cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
-
-
-
-
                }
 
                cap &= CIFS_UNIX_CAP_MASK;
@@ -2176,13 +2189,17 @@ cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb,
 
                /* 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 if (cifs_sb->rsize > (1024 * 127)) {
+               else
+                       tcon->unix_ext = 0; /* server does not support them */
+
+               if ((tcon->unix_ext == 0) && (cifs_sb->rsize > (1024 * 127))) {
                        cifs_sb->rsize = 1024 * 127;
 #ifdef CONFIG_CIFS_DEBUG2
-                       cFYI(1, ("no very large read support, rsize 127K"));
+                       cFYI(1, ("no very large read support, rsize now 127K"));
 #endif
-
                }
                if (!(tcon->ses->capabilities & CAP_LARGE_WRITE_X))
                        cifs_sb->wsize = min(cifs_sb->wsize,

diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c
index def89f2..4830acc 100644 (file)
--- a/fs/cifs/dir.c
+++ b/fs/cifs/dir.c
@@ -207,8 +207,7 @@ cifs_create(struct inode *inode, struct dentry *direntry, int mode,
        } else {
                /* If Open reported that we actually created a file
                then we now have to set the mode if possible */
-               if ((cifs_sb->tcon->ses->capabilities & CAP_UNIX) &&
-                       (oplock & CIFS_CREATE_ACTION)) {
+               if ((pTcon->unix_ext) && (oplock & CIFS_CREATE_ACTION)) {
                        mode &= ~current->fs->umask;
                        if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
                                CIFSSMBUnixSetPerms(xid, pTcon, full_path, mode,
@@ -235,8 +234,8 @@ cifs_create(struct inode *inode, struct dentry *direntry, int mode,
                        /* Could set r/o dos attribute if mode & 0222 == 0 */
                }
 
-       /* BB server might mask mode so we have to query for Unix case*/
-               if (pTcon->ses->capabilities & CAP_UNIX)
+               /* server might mask mode so we have to query for it */
+               if (pTcon->unix_ext)
                        rc = cifs_get_inode_info_unix(&newinode, full_path,
                                                 inode->i_sb, xid);
                else {
@@ -337,7 +336,7 @@ int cifs_mknod(struct inode *inode, struct dentry *direntry, int mode,
        full_path = build_path_from_dentry(direntry);
        if (full_path == NULL)
                rc = -ENOMEM;
-       else if (pTcon->ses->capabilities & CAP_UNIX) {
+       else if (pTcon->unix_ext) {
                mode &= ~current->fs->umask;
                if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
                        rc = CIFSSMBUnixSetPerms(xid, pTcon, full_path,
@@ -491,7 +490,7 @@ cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
        cFYI(1,
             (" Full path: %s inode = 0x%p", full_path, direntry->d_inode));
 
-       if (pTcon->ses->capabilities & CAP_UNIX)
+       if (pTcon->unix_ext)
                rc = cifs_get_inode_info_unix(&newInode, full_path,
                                              parent_dir_inode->i_sb, xid);
        else

diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 0a39491..e13592a 100644 (file)
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -138,7 +138,7 @@ static inline int cifs_open_inode_helper(struct inode *inode, struct file *file,
        }
 
 client_can_cache:
-       if (pTcon->ses->capabilities & CAP_UNIX)
+       if (pTcon->unix_ext)
                rc = cifs_get_inode_info_unix(&file->f_path.dentry->d_inode,
                        full_path, inode->i_sb, xid);
        else
@@ -303,7 +303,7 @@ int cifs_open(struct inode *inode, struct file *file)
        if (oplock & CIFS_CREATE_ACTION) {
                /* time to set mode which we can not set earlier due to
                   problems creating new read-only files */
-               if (cifs_sb->tcon->ses->capabilities & CAP_UNIX) {
+               if (pTcon->unix_ext) {
                        CIFSSMBUnixSetPerms(xid, pTcon, full_path,
                                            inode->i_mode,
                                            (__u64)-1, (__u64)-1, 0 /* dev */,
@@ -430,7 +430,7 @@ reopen_error_exit:
                           go to server to get inode info */
                                pCifsInode->clientCanCacheAll = FALSE;
                                pCifsInode->clientCanCacheRead = FALSE;
-                               if (pTcon->ses->capabilities & CAP_UNIX)
+                               if (pTcon->unix_ext)
                                        rc = cifs_get_inode_info_unix(&inode,
                                                full_path, inode->i_sb, xid);
                                else

diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 3482879..dd41677 100644 (file)
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -583,7 +583,8 @@ void cifs_read_inode(struct inode *inode)
 
        cifs_sb = CIFS_SB(inode->i_sb);
        xid = GetXid();
-       if (cifs_sb->tcon->ses->capabilities & CAP_UNIX)
+
+       if (cifs_sb->tcon->unix_ext)
                cifs_get_inode_info_unix(&inode, "", inode->i_sb, xid);
        else
                cifs_get_inode_info(&inode, "", NULL, inode->i_sb, xid);
@@ -981,7 +982,7 @@ int cifs_mkdir(struct inode *inode, struct dentry *direntry, int mode)
        } else {
 mkdir_get_info:
                inc_nlink(inode);
-               if (pTcon->ses->capabilities & CAP_UNIX)
+               if (pTcon->unix_ext)
                        rc = cifs_get_inode_info_unix(&newinode, full_path,
                                                      inode->i_sb, xid);
                else
@@ -997,7 +998,7 @@ mkdir_get_info:
                  * failed to get it from the server or was set bogus */
                if ((direntry->d_inode) && (direntry->d_inode->i_nlink < 2))
                                direntry->d_inode->i_nlink = 2;
-               if (cifs_sb->tcon->ses->capabilities & CAP_UNIX) {
+               if (pTcon->unix_ext) {
                        mode &= ~current->fs->umask;
                        if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
                                CIFSSMBUnixSetPerms(xid, pTcon, full_path,
@@ -1130,7 +1131,7 @@ int cifs_rename(struct inode *source_inode, struct dentry *source_direntry,
                        kmalloc(2 * sizeof(FILE_UNIX_BASIC_INFO), GFP_KERNEL);
                if (info_buf_source != NULL) {
                        info_buf_target = info_buf_source + 1;
-                       if (pTcon->ses->capabilities & CAP_UNIX)
+                       if (pTcon->unix_ext)
                                rc = CIFSSMBUnixQPathInfo(xid, pTcon, fromName,
                                        info_buf_source,
                                        cifs_sb_source->local_nls,
@@ -1258,7 +1259,7 @@ int cifs_revalidate(struct dentry *direntry)
        local_mtime = direntry->d_inode->i_mtime;
        local_size = direntry->d_inode->i_size;
 
-       if (cifs_sb->tcon->ses->capabilities & CAP_UNIX) {
+       if (cifs_sb->tcon->unix_ext) {
                rc = cifs_get_inode_info_unix(&direntry->d_inode, full_path,
                                              direntry->d_sb, xid);
                if (rc) {
@@ -1542,7 +1543,7 @@ int cifs_setattr(struct dentry *direntry, struct iattr *attrs)
                mode = attrs->ia_mode;
        }
 
-       if ((cifs_sb->tcon->ses->capabilities & CAP_UNIX)
+       if ((pTcon->unix_ext)
            && (attrs->ia_valid & (ATTR_MODE | ATTR_GID | ATTR_UID)))
                rc = CIFSSMBUnixSetPerms(xid, pTcon, full_path, mode, uid, gid,
                                         0 /* dev_t */, cifs_sb->local_nls,

diff --git a/fs/cifs/link.c b/fs/cifs/link.c
index 7da755c..6a85ef7 100644 (file)
--- a/fs/cifs/link.c
+++ b/fs/cifs/link.c
@@ -55,7 +55,8 @@ cifs_hardlink(struct dentry *old_file, struct inode *inode,
                goto cifs_hl_exit;
        }
 
-       if (cifs_sb_target->tcon->ses->capabilities & CAP_UNIX)
+/*     if (cifs_sb_target->tcon->ses->capabilities & CAP_UNIX)*/
+       if (pTcon->unix_ext)
                rc = CIFSUnixCreateHardLink(xid, pTcon, fromName, toName,
                                            cifs_sb_target->local_nls,
                                            cifs_sb_target->mnt_cifs_flags &
@@ -129,14 +130,19 @@ cifs_follow_link(struct dentry *direntry, struct nameidata *nd)
                goto out;
        }
 
-       /* BB add read reparse point symlink code and Unix extensions
-          symlink code here BB */
+       /* We could change this to:
+               if (pTcon->unix_ext)
+          but there does not seem any point in refusing to
+          get symlink info if we can, even if unix extensions
+          turned off for this mount */
+
        if (pTcon->ses->capabilities & CAP_UNIX)
                rc = CIFSSMBUnixQuerySymLink(xid, pTcon, full_path,
                                             target_path,
                                             PATH_MAX-1,
                                             cifs_sb->local_nls);
        else {
+               /* BB add read reparse point symlink code here */
                /* rc = CIFSSMBQueryReparseLinkInfo */
                /* BB Add code to Query ReparsePoint info */
                /* BB Add MAC style xsymlink check here if enabled */
@@ -186,7 +192,7 @@ cifs_symlink(struct inode *inode, struct dentry *direntry, const char *symname)
        cFYI(1, ("symname is %s", symname));
 
        /* BB what if DFS and this volume is on different share? BB */
-       if (cifs_sb->tcon->ses->capabilities & CAP_UNIX)
+       if (pTcon->unix_ext)
                rc = CIFSUnixCreateSymLink(xid, pTcon, full_path, symname,
                                           cifs_sb->local_nls);
        /* else
@@ -194,7 +200,7 @@ cifs_symlink(struct inode *inode, struct dentry *direntry, const char *symname)
                                        cifs_sb_target->local_nls); */
 
        if (rc == 0) {
-               if (pTcon->ses->capabilities & CAP_UNIX)
+               if (pTcon->unix_ext)
                        rc = cifs_get_inode_info_unix(&newinode, full_path,
                                                      inode->i_sb, xid);
                else
@@ -266,6 +272,7 @@ cifs_readlink(struct dentry *direntry, char __user *pBuffer, int buflen)
 
 /* BB add read reparse point symlink code and
        Unix extensions symlink code here BB */
+/* We could disable this based on pTcon->unix_ext flag instead ... but why? */
        if (cifs_sb->tcon->ses->capabilities & CAP_UNIX)
                rc = CIFSSMBUnixQuerySymLink(xid, pTcon, full_path,
                                tmpbuffer,

diff --git a/fs/cifs/readdir.c b/fs/cifs/readdir.c
index 07f9253..916df94 100644 (file)
--- a/fs/cifs/readdir.c
+++ b/fs/cifs/readdir.c
@@ -463,7 +463,9 @@ static int initiate_cifs_search(const int xid, struct file *file)
 
 ffirst_retry:
        /* test for Unix extensions */
-       if (pTcon->ses->capabilities & CAP_UNIX) {
+       /* but now check for them on the share/mount not on the SMB session */
+/*     if (pTcon->ses->capabilities & CAP_UNIX) { */
+       if (pTcon->unix_ext) {
                cifsFile->srch_inf.info_level = SMB_FIND_FILE_UNIX;
        } else if ((pTcon->ses->capabilities &
                        (CAP_NT_SMBS | CAP_NT_FIND)) == 0) {