Re: [mic:next 4/9] fs/open.c:191: undefined reference to `security_file_truncate'

[Mickaël Salaün]

This build error arises when CONFIG_SECURITY_PATH is disabled. Indeed, 
security_file_truncate() is only defined in security/security.c for such 
option.

I have pushed the (rebased) fix in my next branch. FYI, you can keep the 
current Acked-by.

Original patch: 
https://lore.kernel.org/all/20220908195805.128252-2-gnoack3000@xxxxxxxxx/


On 30/09/2022 04:57, kernel test robot wrote:
> tree:   git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux.git next
> head:   054fdc359167ae7c17a5fb47c0edbf5cb4b737b0
> commit: 0052f28b7cba97cefa48623ef087d1c1cc06078f [4/9] security: create file_truncate hook from path_truncate hook
> config: x86_64-rhel-8.3-func
> compiler: gcc-11 (Debian 11.3.0-5) 11.3.0
> reproduce (this is a W=1 build):
>          # https://git.kernel.org/pub/scm/linux/kernel/git/mic/linux.git/commit/?id=0052f28b7cba97cefa48623ef087d1c1cc06078f
>          git remote add mic git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux.git
>          git fetch --no-tags mic next
>          git checkout 0052f28b7cba97cefa48623ef087d1c1cc06078f
>          # save the config file
>          mkdir build_dir && cp config build_dir/.config
>          make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash
>
> If you fix the issue, kindly add following tag where applicable
> | Reported-by: kernel test robot <lkp@xxxxxxxxx>
>
> All errors (new ones prefixed by >>):
>
>     ld: fs/open.o: in function `do_sys_ftruncate':
> > > fs/open.c:191: undefined reference to `security_file_truncate'
>     ld: fs/namei.o: in function `handle_truncate':
> > > fs/namei.c:3214: undefined reference to `security_file_truncate'
>
>
> vim +191 fs/open.c
>
>     155	
>     156	long do_sys_ftruncate(unsigned int fd, loff_t length, int small)
>     157	{
>     158		struct inode *inode;
>     159		struct dentry *dentry;
>     160		struct fd f;
>     161		int error;
>     162	
>     163		error = -EINVAL;
>     164		if (length < 0)
>     165			goto out;
>     166		error = -EBADF;
>     167		f = fdget(fd);
>     168		if (!f.file)
>     169			goto out;
>     170	
>     171		/* explicitly opened as large or we are on 64-bit box */
>     172		if (f.file->f_flags & O_LARGEFILE)
>     173			small = 0;
>     174	
>     175		dentry = f.file->f_path.dentry;
>     176		inode = dentry->d_inode;
>     177		error = -EINVAL;
>     178		if (!S_ISREG(inode->i_mode) || !(f.file->f_mode & FMODE_WRITE))
>     179			goto out_putf;
>     180	
>     181		error = -EINVAL;
>     182		/* Cannot ftruncate over 2^31 bytes without large file support */
>     183		if (small && length > MAX_NON_LFS)
>     184			goto out_putf;
>     185	
>     186		error = -EPERM;
>     187		/* Check IS_APPEND on real upper inode */
>     188		if (IS_APPEND(file_inode(f.file)))
>     189			goto out_putf;
>     190		sb_start_write(inode->i_sb);
>   > 191		error = security_file_truncate(f.file);
>     192		if (!error)
>     193			error = do_truncate(file_mnt_user_ns(f.file), dentry, length,
>     194					    ATTR_MTIME | ATTR_CTIME, f.file);
>     195		sb_end_write(inode->i_sb);
>     196	out_putf:
>     197		fdput(f);
>     198	out:
>     199		return error;
>     200	}
>     201