cifs: Use file_dentry()

CIFS may be used as lower layer of overlayfs and accessing f_path.dentry can
lead to a crash.

Fix by replacing direct access of file->f_path.dentry with the
file_dentry() accessor, which will always return a native object.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Acked-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <smfrench@gmail.com>
This commit is contained in:
Goldwyn Rodrigues 2016-04-18 06:41:52 -05:00 committed by Steve French
parent 7f427d3a60
commit 1f1735cb75
2 changed files with 4 additions and 4 deletions

View File

@ -271,7 +271,7 @@ struct cifsFileInfo *
cifs_new_fileinfo(struct cifs_fid *fid, struct file *file,
struct tcon_link *tlink, __u32 oplock)
{
struct dentry *dentry = file->f_path.dentry;
struct dentry *dentry = file_dentry(file);
struct inode *inode = d_inode(dentry);
struct cifsInodeInfo *cinode = CIFS_I(inode);
struct cifsFileInfo *cfile;
@ -461,7 +461,7 @@ int cifs_open(struct inode *inode, struct file *file)
tcon = tlink_tcon(tlink);
server = tcon->ses->server;
full_path = build_path_from_dentry(file->f_path.dentry);
full_path = build_path_from_dentry(file_dentry(file));
if (full_path == NULL) {
rc = -ENOMEM;
goto out;

View File

@ -303,7 +303,7 @@ initiate_cifs_search(const unsigned int xid, struct file *file)
cifsFile->invalidHandle = true;
cifsFile->srch_inf.endOfSearch = false;
full_path = build_path_from_dentry(file->f_path.dentry);
full_path = build_path_from_dentry(file_dentry(file));
if (full_path == NULL) {
rc = -ENOMEM;
goto error_exit;
@ -762,7 +762,7 @@ static int cifs_filldir(char *find_entry, struct file *file,
*/
fattr.cf_flags |= CIFS_FATTR_NEED_REVAL;
cifs_prime_dcache(file->f_path.dentry, &name, &fattr);
cifs_prime_dcache(file_dentry(file), &name, &fattr);
ino = cifs_uniqueid_to_ino_t(fattr.cf_uniqueid);
return !dir_emit(ctx, name.name, name.len, ino, fattr.cf_dtype);