From a636a9b1306587bbfab54b1e435461289a4c2c35 Mon Sep 17 00:00:00 2001 From: Aurelien Aptel Date: Wed, 25 May 2016 19:59:09 +0200 Subject: fs/cifs: make share unaccessible at root level mountable commit a6b5058fafdf508904bbf16c29b24042cef3c496 upstream. if, when mounting //HOST/share/sub/dir/foo we can query /sub/dir/foo but not any of the path components above: - store the /sub/dir/foo prefix in the cifs super_block info - in the superblock, set root dentry to the subpath dentry (instead of the share root) - set a flag in the superblock to remember it - use prefixpath when building path from a dentry fixes bso#8950 Signed-off-by: Aurelien Aptel Reviewed-by: Pavel Shilovsky Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman --- fs/cifs/dir.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) (limited to 'fs/cifs/dir.c') diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c index c3eb998a99bd..b95bffcee8aa 100644 --- a/fs/cifs/dir.c +++ b/fs/cifs/dir.c @@ -84,6 +84,7 @@ build_path_from_dentry(struct dentry *direntry) struct dentry *temp; int namelen; int dfsplen; + int pplen = 0; char *full_path; char dirsep; struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb); @@ -95,8 +96,12 @@ build_path_from_dentry(struct dentry *direntry) dfsplen = strnlen(tcon->treeName, MAX_TREE_SIZE + 1); else dfsplen = 0; + + if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) + pplen = cifs_sb->prepath ? strlen(cifs_sb->prepath) + 1 : 0; + cifs_bp_rename_retry: - namelen = dfsplen; + namelen = dfsplen + pplen; seq = read_seqbegin(&rename_lock); rcu_read_lock(); for (temp = direntry; !IS_ROOT(temp);) { @@ -137,7 +142,7 @@ cifs_bp_rename_retry: } } rcu_read_unlock(); - if (namelen != dfsplen || read_seqretry(&rename_lock, seq)) { + if (namelen != dfsplen + pplen || read_seqretry(&rename_lock, seq)) { cifs_dbg(FYI, "did not end path lookup where expected. namelen=%ddfsplen=%d\n", namelen, dfsplen); /* presumably this is only possible if racing with a rename @@ -153,6 +158,17 @@ cifs_bp_rename_retry: those safely to '/' if any are found in the middle of the prepath */ /* BB test paths to Windows with '/' in the midst of prepath */ + if (pplen) { + int i; + + cifs_dbg(FYI, "using cifs_sb prepath <%s>\n", cifs_sb->prepath); + memcpy(full_path+dfsplen+1, cifs_sb->prepath, pplen-1); + full_path[dfsplen] = '\\'; + for (i = 0; i < pplen-1; i++) + if (full_path[dfsplen+1+i] == '/') + full_path[dfsplen+1+i] = CIFS_DIR_SEP(cifs_sb); + } + if (dfsplen) { strncpy(full_path, tcon->treeName, dfsplen); if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS) { -- cgit v1.2.3