diff options
| -rw-r--r-- | fs/namei.c | 109 |
1 files changed, 56 insertions, 53 deletions
@@ -1444,69 +1444,52 @@ int may_open(struct path *path, int acc_mode, int flag) if (error) return error; - error = ima_path_check(path, acc_mode ? - acc_mode & (MAY_READ | MAY_WRITE | MAY_EXEC) : - ACC_MODE(flag) & (MAY_READ | MAY_WRITE), - IMA_COUNT_UPDATE); - - if (error) - return error; /* * An append-only file must be opened in append mode for writing. */ if (IS_APPEND(inode)) { - error = -EPERM; if ((flag & FMODE_WRITE) && !(flag & O_APPEND)) - goto err_out; + return -EPERM; if (flag & O_TRUNC) - goto err_out; + return -EPERM; } /* O_NOATIME can only be set by the owner or superuser */ - if (flag & O_NOATIME) - if (!is_owner_or_cap(inode)) { - error = -EPERM; - goto err_out; - } + if (flag & O_NOATIME && !is_owner_or_cap(inode)) + return -EPERM; /* * Ensure there are no outstanding leases on the file. */ error = break_lease(inode, flag); if (error) - goto err_out; - - if (flag & O_TRUNC) { - error = get_write_access(inode); - if (error) - goto err_out; - - /* - * Refuse to truncate files with mandatory locks held on them. - */ - error = locks_verify_locked(inode); - if (!error) - error = security_path_truncate(path, 0, - ATTR_MTIME|ATTR_CTIME|ATTR_OPEN); - if (!error) { - vfs_dq_init(inode); + return error; - error = do_truncate(dentry, 0, - ATTR_MTIME|ATTR_CTIME|ATTR_OPEN, - NULL); - } - put_write_access(inode); - if (error) - goto err_out; - } else - if (flag & FMODE_WRITE) - vfs_dq_init(inode); + return ima_path_check(path, acc_mode ? + acc_mode & (MAY_READ | MAY_WRITE | MAY_EXEC) : + ACC_MODE(flag) & (MAY_READ | MAY_WRITE), + IMA_COUNT_UPDATE); +} - return 0; -err_out: - ima_counts_put(path, acc_mode ? - acc_mode & (MAY_READ | MAY_WRITE | MAY_EXEC) : - ACC_MODE(flag) & (MAY_READ | MAY_WRITE)); +static int handle_truncate(struct path *path) +{ + struct inode *inode = path->dentry->d_inode; + int error = get_write_access(inode); + if (error) + return error; + /* + * Refuse to truncate files with mandatory locks held on them. + */ + error = locks_verify_locked(inode); + if (!error) + error = security_path_truncate(path, 0, + ATTR_MTIME|ATTR_CTIME|ATTR_OPEN); + if (!error) { + error = do_truncate(path->dentry, 0, + ATTR_MTIME|ATTR_CTIME|ATTR_OPEN, + NULL); + } + put_write_access(inode); return error; } @@ -1561,7 +1544,7 @@ static inline int open_to_namei_flags(int flag) return flag; } -static int open_will_write_to_fs(int flag, struct inode *inode) +static int open_will_truncate(int flag, struct inode *inode) { /* * We'll never write to the fs underlying @@ -1586,7 +1569,7 @@ struct file *do_filp_open(int dfd, const char *pathname, struct path path, save; struct dentry *dir; int count = 0; - int will_write; + int will_truncate; int flag = open_to_namei_flags(open_flag); /* @@ -1752,28 +1735,48 @@ ok: * be avoided. Taking this mnt write here * ensures that (2) can not occur. */ - will_write = open_will_write_to_fs(flag, nd.path.dentry->d_inode); - if (will_write) { + will_truncate = open_will_truncate(flag, nd.path.dentry->d_inode); + if (will_truncate) { error = mnt_want_write(nd.path.mnt); if (error) goto exit; } error = may_open(&nd.path, acc_mode, flag); if (error) { - if (will_write) + if (will_truncate) mnt_drop_write(nd.path.mnt); goto exit; } filp = nameidata_to_filp(&nd, open_flag); - if (IS_ERR(filp)) + if (IS_ERR(filp)) { ima_counts_put(&nd.path, acc_mode & (MAY_READ | MAY_WRITE | MAY_EXEC)); + if (will_truncate) + mnt_drop_write(nd.path.mnt); + if (nd.root.mnt) + path_put(&nd.root); + return filp; + } + + if (acc_mode & MAY_WRITE) + vfs_dq_init(nd.path.dentry->d_inode); + + if (will_truncate) { + error = handle_truncate(&nd.path); + if (error) { + mnt_drop_write(nd.path.mnt); + fput(filp); + if (nd.root.mnt) + path_put(&nd.root); + return ERR_PTR(error); + } + } /* * It is now safe to drop the mnt write * because the filp has had a write taken * on its behalf. */ - if (will_write) + if (will_truncate) mnt_drop_write(nd.path.mnt); if (nd.root.mnt) path_put(&nd.root); |
