lkml.org 
[lkml]   [2018]   [Apr]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: [PATCH?] reiserfs: prevent panic: don't allow %-char in journal dev. name
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@infradead.org> wrote:
> >
> >> From: Randy Dunlap <rdunlap@infradead.org>
> >>
> >> 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@suse.com>

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@suse.com>
SUSE Labs, CR
From 121724c8bb9d5c07ee12718520f6f99b0da0a275 Mon Sep 17 00:00:00 2001
From: Andrew Morton <akpm@linux-foundation.org>
Date: Mon, 9 Apr 2018 16:17:44 +0200
Subject: [PATCH] reiserfs: Fix warning for non-existing journal devices

When a journal device specified as part of mount options does not exist,
reiserfs issues a warking like:

reiserfs_warning(super,
"journal_init_dev: Cannot open '%s': %i",
jdev_name, result);

Now this misses a parameter 'id' of reiserfs_warning() which comes
second. As such, the format string is interpreted as an ID and jdev_name as
a format string resulting in funny issues.

Fix the problem by adding missing 'id' argument.

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Jan Kara <jack@suse.cz>
---
fs/reiserfs/journal.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/reiserfs/journal.c b/fs/reiserfs/journal.c
index 70057359fbaf..23148c3ed675 100644
--- a/fs/reiserfs/journal.c
+++ b/fs/reiserfs/journal.c
@@ -2643,7 +2643,7 @@ static int journal_init_dev(struct super_block *super,
if (IS_ERR(journal->j_dev_bd)) {
result = PTR_ERR(journal->j_dev_bd);
journal->j_dev_bd = NULL;
- reiserfs_warning(super,
+ reiserfs_warning(super, "sh-457",
"journal_init_dev: Cannot open '%s': %i",
jdev_name, result);
return result;
--
2.13.6
\
 
 \ /
  Last update: 2018-04-09 16:25    [W:0.120 / U:0.020 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site