From: Jens Axboe <axboe@kernel.dk>
To: Dan Williams <dan.j.williams@intel.com>
Cc: Sachin Sant <sachinp@linux.vnet.ibm.com>,
Christoph Hellwig <hch@lst.de>,
Ulf Hansson <ulf.hansson@linaro.org>,
nvdimm@lists.linux.dev, linux-block@vger.kernel.org,
linuxppc-dev@lists.ozlabs.org
Subject: Re: [PATCH v2] libnvdimm/pmem: Fix blk_cleanup_disk() usage
Date: Tue, 8 Jun 2021 15:26:50 -0600 [thread overview]
Message-ID: <1b2082fc-be01-ad2f-9dd5-aa66b1c0ce85@kernel.dk> (raw)
In-Reply-To: <162310994435.1571616.334551212901820961.stgit@dwillia2-desk3.amr.corp.intel.com>
On 6/7/21 5:52 PM, Dan Williams wrote:
> The queue_to_disk() helper can not be used after del_gendisk()
> communicate @disk via the pgmap->owner.
>
> Otherwise, queue_to_disk() returns NULL resulting in the splat below.
>
> Kernel attempted to read user page (330) - exploit attempt? (uid: 0)
> BUG: Kernel NULL pointer dereference on read at 0x00000330
> Faulting instruction address: 0xc000000000906344
> Oops: Kernel access of bad area, sig: 11 [#1]
> [..]
> NIP [c000000000906344] pmem_pagemap_cleanup+0x24/0x40
> LR [c0000000004701d4] memunmap_pages+0x1b4/0x4b0
> Call Trace:
> [c000000022cbb9c0] [c0000000009063c8] pmem_pagemap_kill+0x28/0x40 (unreliable)
> [c000000022cbb9e0] [c0000000004701d4] memunmap_pages+0x1b4/0x4b0
> [c000000022cbba90] [c0000000008b28a0] devm_action_release+0x30/0x50
> [c000000022cbbab0] [c0000000008b39c8] release_nodes+0x2f8/0x3e0
> [c000000022cbbb60] [c0000000008ac440] device_release_driver_internal+0x190/0x2b0
> [c000000022cbbba0] [c0000000008a8450] unbind_store+0x130/0x170
Applied, thanks.
--
Jens Axboe
prev parent reply other threads:[~2021-06-08 21:26 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-07 23:31 [PATCH] libnvdimm/pmem: Fix blk_cleanup_disk() usage Dan Williams
2021-06-07 23:52 ` [PATCH v2] " Dan Williams
2021-06-08 5:36 ` Christoph Hellwig
2021-06-08 5:43 ` Sachin Sant
2021-06-08 21:26 ` Jens Axboe [this message]
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=1b2082fc-be01-ad2f-9dd5-aa66b1c0ce85@kernel.dk \
--to=axboe@kernel.dk \
--cc=dan.j.williams@intel.com \
--cc=hch@lst.de \
--cc=linux-block@vger.kernel.org \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=nvdimm@lists.linux.dev \
--cc=sachinp@linux.vnet.ibm.com \
--cc=ulf.hansson@linaro.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).