Re: [PATCH?] reiserfs: prevent panic: don't allow %-char in journal dev. name
From: Jan Kara
Date: Mon Apr 09 2018 - 10:25:24 EST
On Wed 04-04-18 21:48:53, Jeff Mahoney wrote:
> On 4/4/18 9:45 PM, Andrew Morton wrote:
> > On Wed, 4 Apr 2018 18:25:16 -0700 Randy Dunlap <rdunlap@xxxxxxxxxxxxx> wrote:
> >
> >> From: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
> >>
> >> If the reiserfs mount option's journal name contains a '%' character,
> >> it can lead to a WARN_ONCE() in lib/vsprintf.c::format_decode(),
> >> saying: "Please remove unsupported %/ in format string."
> >> That's OK until panic_on_warn is set, at which point it's dead, Jim.
> >>
> >> To placate this situation, check the journal name string for a '%'
> >> character and return an error if one is found. Also print a warning
> >> (one that won't panic the kernel) about the invalid journal name (e.g.):
> >>
> >> reiserfs: journal device name is invalid: %/file0
> >>
> >> (In this example, the caller app specified the journal device name as
> >> "%/file0".)
> >>
> >
> > Well, that is a valid filename and we should support it...
> >
> > Isn't the bug in journal_init_dev()?
>
> Yep. That's exactly it.
>
> Acked-by: Jeff Mahoney <jeffm@xxxxxxxx>
Thanks. I've picked up the patch from Andrew, added his Signed-off-by (OK,
Andrew?), wrote a proper changelog and pushed it to my tree. The result is
attached.
Honza
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR