From 8d9535b6efd86e6c07da59f97e68f44efb7fe080 Mon Sep 17 00:00:00 2001 From: Sachin Prabhu Date: Thu, 7 Jul 2016 21:28:27 +0100 Subject: cifs: Check for existing directory when opening file with O_CREAT When opening a file with O_CREAT flag, check to see if the file opened is an existing directory. This prevents the directory from being opened which subsequently causes a crash when the close function for directories cifs_closedir() is called which frees up the file->private_data memory while the file is still listed on the open file list for the tcon. Signed-off-by: Sachin Prabhu Signed-off-by: Steve French CC: Stable Reported-by: Xiaoli Feng --- fs/cifs/dir.c | 24 +++++++++++++++++++++--- 1 file changed, 21 insertions(+), 3 deletions(-) (limited to 'fs/cifs/dir.c') diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c index c3eb998a99bd..5089e426371a 100644 --- a/fs/cifs/dir.c +++ b/fs/cifs/dir.c @@ -229,6 +229,13 @@ cifs_do_create(struct inode *inode, struct dentry *direntry, unsigned int xid, goto cifs_create_get_file_info; } + if (S_ISDIR(newinode->i_mode)) { + CIFSSMBClose(xid, tcon, fid->netfid); + iput(newinode); + rc = -EISDIR; + goto out; + } + if (!S_ISREG(newinode->i_mode)) { /* * The server may allow us to open things like @@ -399,10 +406,14 @@ cifs_create_set_dentry: if (rc != 0) { cifs_dbg(FYI, "Create worked, get_inode_info failed rc = %d\n", rc); - if (server->ops->close) - server->ops->close(xid, tcon, fid); - goto out; + goto out_err; } + + if (S_ISDIR(newinode->i_mode)) { + rc = -EISDIR; + goto out_err; + } + d_drop(direntry); d_add(direntry, newinode); @@ -410,6 +421,13 @@ out: kfree(buf); kfree(full_path); return rc; + +out_err: + if (server->ops->close) + server->ops->close(xid, tcon, fid); + if (newinode) + iput(newinode); + goto out; } int -- cgit v1.2.1 From a6b5058fafdf508904bbf16c29b24042cef3c496 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 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 CC: Stable Reviewed-by: Pavel Shilovsky Signed-off-by: Steve French --- 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 5089e426371a..26a3b389a265 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 v1.2.1