From: "Vlastimil Babka (SUSE)" <vbabka@kernel.org>
To: Matthew Wilcox <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>, Chao Yu <chao@kernel.org>,
Linux MM <linux-mm@kvack.org>,
Andrew Morton <akpm@linux-foundation.org>,
linux-kernel@vger.kernel.org, jaegeuk@kernel.org,
Chao Yu <chao.yu@oppo.com>,
stable@kernel.org,
syzbot+81684812ea68216e08c5@syzkaller.appspotmail.com,
David Rientjes <rientjes@google.com>,
Hyeonggon Yoo <42.hyeyoo@gmail.com>,
Christoph Lameter <cl@linux.com>,
Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Subject: Re: [PATCH] mm/slub: fix to return errno if kmalloc() fails
Date: Fri, 9 Sep 2022 22:21:41 +0200 [thread overview]
Message-ID: <8abfed2c-2499-b2da-1e06-ecc188f7c7b0@kernel.org> (raw)
In-Reply-To: <Yxucs30FNkbWQHVh@casper.infradead.org>
On 9/9/22 22:06, Matthew Wilcox wrote:
> On Thu, Sep 08, 2022 at 11:25:08PM +0200, Vlastimil Babka (SUSE) wrote:
>> > I tend to agree with you. A mount operation shouldn’t panic the
>> > kernel.
>>
>> Hmm kmalloc(64) shouldn't normally due that due to the the underlying page
>> allocation falling into the "too small to fail" category, wonder if
>> syzkaller was doing anything special here?
>
> Here's the repro:
>
> https://syzkaller.appspot.com/x/repro.c?x=17cd7fa3080000
>
> you can see it does:
>
> fd = open("/proc/thread-self/fail-nth", O_RDWR);
> if (fd == -1)
> exit(1);
> char buf[16];
> sprintf(buf, "%d", nth);
> if (write(fd, buf, strlen(buf)) != (ssize_t)strlen(buf))
>
> so this is the kind of stupid nitpicky bug that we shouldn't be
> reporting, let alone fixing, IMO.
Ah, thanks.
Well I'm ok with eventually removing all such BUG_ONs including what
Christophe Jaillet suggested, but it certainly isn't urgent nor deserves Cc:
stable then.
next prev parent reply other threads:[~2022-09-09 20:21 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-08-30 14:10 [PATCH] mm/slub: fix to return errno if kmalloc() fails Chao Yu
2022-08-31 3:09 ` Muchun Song
2022-09-08 21:25 ` Vlastimil Babka (SUSE)
2022-09-09 20:06 ` Matthew Wilcox
2022-09-09 20:21 ` Vlastimil Babka (SUSE) [this message]
2022-09-13 3:27 ` Chao Yu
2022-08-31 13:33 ` Hyeonggon Yoo
2022-09-06 21:33 ` David Rientjes
2022-09-09 16:47 ` Christophe JAILLET
2022-09-13 3:42 ` Chao Yu
2022-09-13 5:26 ` Marion & Christophe JAILLET
2022-09-16 22:58 ` Vlastimil Babka (SUSE)
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=8abfed2c-2499-b2da-1e06-ecc188f7c7b0@kernel.org \
--to=vbabka@kernel.org \
--cc=42.hyeyoo@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=chao.yu@oppo.com \
--cc=chao@kernel.org \
--cc=christophe.jaillet@wanadoo.fr \
--cc=cl@linux.com \
--cc=jaegeuk@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=muchun.song@linux.dev \
--cc=rientjes@google.com \
--cc=stable@kernel.org \
--cc=syzbot+81684812ea68216e08c5@syzkaller.appspotmail.com \
--cc=willy@infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).