diff options
Diffstat (limited to 'fs/open.c')
| -rw-r--r-- | fs/open.c | 35 |
1 files changed, 29 insertions, 6 deletions
diff --git a/fs/open.c b/fs/open.c index 48afc5c139d2..14a51de01f54 100644 --- a/fs/open.c +++ b/fs/open.c @@ -669,11 +669,16 @@ static struct file *__dentry_open(struct dentry *dentry, struct vfsmount *mnt, int (*open)(struct inode *, struct file *), const struct cred *cred) { + static const struct file_operations empty_fops = {}; struct inode *inode; int error; f->f_mode = OPEN_FMODE(f->f_flags) | FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE; + + if (unlikely(f->f_flags & O_PATH)) + f->f_mode = FMODE_PATH; + inode = dentry->d_inode; if (f->f_mode & FMODE_WRITE) { error = __get_file_write_access(inode, mnt); @@ -687,9 +692,15 @@ static struct file *__dentry_open(struct dentry *dentry, struct vfsmount *mnt, f->f_path.dentry = dentry; f->f_path.mnt = mnt; f->f_pos = 0; - f->f_op = fops_get(inode->i_fop); file_sb_list_add(f, inode->i_sb); + if (unlikely(f->f_mode & FMODE_PATH)) { + f->f_op = &empty_fops; + return f; + } + + f->f_op = fops_get(inode->i_fop); + error = security_dentry_open(f, cred); if (error) goto cleanup_all; @@ -911,9 +922,18 @@ static inline int build_open_flags(int flags, int mode, struct open_flags *op) if (flags & __O_SYNC) flags |= O_DSYNC; - op->open_flag = flags; + /* + * If we have O_PATH in the open flag. Then we + * cannot have anything other than the below set of flags + */ + if (flags & O_PATH) { + flags &= O_DIRECTORY | O_NOFOLLOW | O_PATH; + acc_mode = 0; + } else { + acc_mode = MAY_OPEN | ACC_MODE(flags); + } - acc_mode = MAY_OPEN | ACC_MODE(flags); + op->open_flag = flags; /* O_TRUNC implies we need access checks for write permissions */ if (flags & O_TRUNC) @@ -926,7 +946,8 @@ static inline int build_open_flags(int flags, int mode, struct open_flags *op) op->acc_mode = acc_mode; - op->intent = LOOKUP_OPEN; + op->intent = flags & O_PATH ? 0 : LOOKUP_OPEN; + if (flags & O_CREAT) { op->intent |= LOOKUP_CREATE; if (flags & O_EXCL) @@ -1053,8 +1074,10 @@ int filp_close(struct file *filp, fl_owner_t id) if (filp->f_op && filp->f_op->flush) retval = filp->f_op->flush(filp, id); - dnotify_flush(filp, id); - locks_remove_posix(filp, id); + if (likely(!(filp->f_mode & FMODE_PATH))) { + dnotify_flush(filp, id); + locks_remove_posix(filp, id); + } fput(filp); return retval; } |