diff options
| author | Sachin Prabhu <sprabhu@redhat.com> | 2016-07-07 21:28:27 +0100 |
|---|---|---|
| committer | Jiri Slaby <jslaby@suse.cz> | 2016-08-19 09:51:14 +0200 |
| commit | 856101261eaa4e9da8ba71ce0252df551a170a0c (patch) | |
| tree | e4667759d864a9971922e074fc50620ca22f7a6f /fs | |
| parent | f01e595635c55d732fba1b0d2542994fb7c5b9ce (diff) | |
| download | lwn-856101261eaa4e9da8ba71ce0252df551a170a0c.tar.gz lwn-856101261eaa4e9da8ba71ce0252df551a170a0c.zip | |
cifs: Check for existing directory when opening file with O_CREAT
commit 8d9535b6efd86e6c07da59f97e68f44efb7fe080 upstream.
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 <sprabhu@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reported-by: Xiaoli Feng <xifeng@redhat.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/cifs/dir.c | 24 |
1 files changed, 21 insertions, 3 deletions
diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c index f039c23d003d..7347f1678fa7 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 |