From: Chao Yu <chao@kernel.org>
To: Dongliang Mu <mudongliangabcd@gmail.com>,
Jaegeuk Kim <jaegeuk@kernel.org>,
Sahitya Tummala <stummala@codeaurora.org>
Cc: linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] fs: f2fs: fix UAF in f2fs_available_free_memory
Date: Thu, 4 Nov 2021 16:37:41 +0800 [thread overview]
Message-ID: <b071e877-334e-b669-e2df-abe4d5927418@kernel.org> (raw)
In-Reply-To: <20211104082202.1286551-1-mudongliangabcd@gmail.com>
On 2021/11/4 16:22, Dongliang Mu wrote:
> if2fs_fill_super
> -> f2fs_build_segment_manager
> -> create_discard_cmd_control
> -> f2fs_start_discard_thread
>
> It invokes kthread_run to create a thread and run issue_discard_thread.
>
> However, if f2fs_build_node_manager fails, the control flow goes to
> free_nm and calls f2fs_destroy_node_manager. This function will free
> sbi->nm_info. However, if issue_discard_thread accesses sbi->nm_info
> after the deallocation, but before the f2fs_stop_discard_thread, it will
> cause UAF(Use-after-free).
>
> -> f2fs_destroy_segment_manager
> -> destroy_discard_cmd_control
> -> f2fs_stop_discard_thread
>
> Fix this by stopping discard thread before f2fs_destroy_node_manager.
>
> Note that, the commit d6d2b491a82e1 introduces the call of
> f2fs_available_free_memory into issue_discard_thread.
>
> Fixes: d6d2b491a82e ("f2fs: allow to change discard policy based on cached discard cmds")
> Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Thanks,
prev parent reply other threads:[~2021-11-04 8:37 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-11-04 8:22 [PATCH v2] fs: f2fs: fix UAF in f2fs_available_free_memory Dongliang Mu
2021-11-04 8:37 ` Chao Yu [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=b071e877-334e-b669-e2df-abe4d5927418@kernel.org \
--to=chao@kernel.org \
--cc=jaegeuk@kernel.org \
--cc=linux-f2fs-devel@lists.sourceforge.net \
--cc=linux-kernel@vger.kernel.org \
--cc=mudongliangabcd@gmail.com \
--cc=stummala@codeaurora.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).