Re: [PATCH] fs: Use CHECK_DATA_CORRUPTION() when kernel bugs are detected

[Kees Cook]

On Fri, Jan 27, 2023 at 11:58:15AM +0100, Christian Brauner wrote:
> On Thu, Jan 26, 2023 at 08:35:49AM -0800, Kees Cook wrote:
> > On Mon, Jan 16, 2023 at 08:14:25PM +0100, Jann Horn wrote:
> > > Currently, filp_close() and generic_shutdown_super() use printk() to log
> > > messages when bugs are detected. This is problematic because infrastructure
> > > like syzkaller has no idea that this message indicates a bug.
> > > In addition, some people explicitly want their kernels to BUG() when kernel
> > > data corruption has been detected (CONFIG_BUG_ON_DATA_CORRUPTION).
> > > And finally, when generic_shutdown_super() detects remaining inodes on a
> > > system without CONFIG_BUG_ON_DATA_CORRUPTION, it would be nice if later
> > > accesses to a busy inode would at least crash somewhat cleanly rather than
> > > walking through freed memory.
> > > 
> > > To address all three, use CHECK_DATA_CORRUPTION() when kernel bugs are
> > > detected.
> > 
> > Seems reasonable to me. I'll carry this unless someone else speaks up.
> 
> I've already picked this into a branch with other fs changes for coming cycle.

Okay, great! I'll drop it from my tree.

Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>

-- 
Kees Cook