From: Walter Alejandro Iglesias <wai@roquesor.com>
Subject: Re: Message when moving file to ext2
To: Martijn van Duren <openbsd+tech@list.imperialat.at>
Cc: tech@openbsd.org
Date: Thu, 23 Oct 2025 10:13:48 +0200

Hi Martijn,

On Thu, Oct 23, 2025 at 02:14:41AM +0200, Martijn van Duren wrote:
> On Wed, 2025-10-22 at 21:35 +0200, Walter Alejandro Iglesias wrote:
> > Hello list,
> > 
> > Is the message below expected when moving a file to an ext2 file system?
> > 
> >   $ doas mount -t ext2fs /dev/sd1i /mnt
> >   $ mv file /mnt
> >   mv: /mnt/file: set flags: Operation not permitted
> > 
> Moving to tech@
> 
> I ran into this issue some time ago with install(1). Back then I fixed
> it by making sure that install(1) doesn't call chflags(2) when the flags
> are identical.
> 
> The culprit for this warning is the following diff[0], which now always
> returns EPERM when a user tries to change flags (which we clearly aren't
> trying to do). Since I can't tell which other tools might bite us I
> think it might be wise to implement the logic I put into install(1) into
> the ext2fs driver.
> 
> The diff below works on my machine(tm). Could you give it a spin?

I applied your diff, compiled and installed the kernel, reboot (did I do
it right, or am I missing a step?), but the message is still appearing.


> 
> martijn@
> 
> ps. ext2 has a few more flags than our tools support[1]. But we could
> add nodump to the mapping, if only for a bit more complete insight.
> pps. Maybe it's a good idea to return EINVAL for UF_IMMUTABLE,
> UF_APPEND, and SF_ARCHIVED. That way it will be clear for the
> admin that certain flags aren't supported and won't be dropped
> silently. 
> 
> [0] https://marc.info/?l=openbsd-tech&m=174499208717194&w=2
> [1] https://wiki.osdev.org/Ext2#Inode_Flags
> 
> diff /usr/src
> path + /usr/src
> commit - 243c12c31b603d599722a28305b1c1bab6ea9d19
> blob - c0ffdeb9166c32d67d308129cd4c7c5b535cc620
> file + sys/ufs/ext2fs/ext2fs_vnops.c
> --- sys/ufs/ext2fs/ext2fs_vnops.c
> +++ sys/ufs/ext2fs/ext2fs_vnops.c
> @@ -210,6 +210,7 @@ ext2fs_setattr(void *v)
>  	struct vnode *vp = ap->a_vp;
>  	struct inode *ip = VTOI(vp);
>  	struct ucred *cred = ap->a_cred;
> +	u_long e2flags;
>  	int error;
>  
>  	/*
> @@ -227,16 +228,17 @@ ext2fs_setattr(void *v)
>  		if (cred->cr_uid != ip->i_e2fs_uid &&
>  			(error = suser_ucred(cred)))
>  			return (error);
> +		e2flags = (vap->va_flags & SF_APPEND) ? EXT2_APPEND : 0 |
> +		    (vap->va_flags & SF_IMMUTABLE) ? EXT2_IMMUTABLE: 0;
>  		if (cred->cr_uid == 0) {
>  			if ((ip->i_e2fs_flags &
>  			    (EXT2_APPEND | EXT2_IMMUTABLE)) && securelevel > 0)
>  				return (EPERM);
>  			ip->i_e2fs_flags &= ~(EXT2_APPEND | EXT2_IMMUTABLE);
> -			ip->i_e2fs_flags |=
> -			    (vap->va_flags & SF_APPEND) ? EXT2_APPEND : 0 |
> -			    (vap->va_flags & SF_IMMUTABLE) ? EXT2_IMMUTABLE: 0;
> +			ip->i_e2fs_flags |= e2flags;
>  		} else {
> -			return (EPERM);
> +			if (e2flags != ip->i_e2fs_flags)
> +				return (EPERM);
>  		}
>  		ip->i_flag |= IN_CHANGE;
>  		if (vap->va_flags & (IMMUTABLE | APPEND))
> 

-- 
Amar: cambiar de casa el alma.
		-- Constancio C. Vigil.