From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: "Paul E. McKenney" <paulmck@kernel.org>,
"Xu, Yanfei" <yanfei.xu@windriver.com>,
Sasha Levin <sashal@kernel.org>,
rcu@vger.kernel.org
Subject: [PATCH AUTOSEL 5.13 05/19] rcu-tasks: Don't delete holdouts within trc_inspect_reader()
Date: Thu, 22 Jul 2021 23:57:06 -0400 [thread overview]
Message-ID: <20210723035721.531372-5-sashal@kernel.org> (raw)
In-Reply-To: <20210723035721.531372-1-sashal@kernel.org>
From: "Paul E. McKenney" <paulmck@kernel.org>
[ Upstream commit 1d10bf55d85d34eb73dd8263635f43fd72135d2d ]
As Yanfei pointed out, although invoking trc_del_holdout() is safe
from the viewpoint of the integrity of the holdout list itself,
the put_task_struct() invoked by trc_del_holdout() can result in
use-after-free errors due to later accesses to this task_struct structure
by the RCU Tasks Trace grace-period kthread.
This commit therefore removes this call to trc_del_holdout() from
trc_inspect_reader() in favor of the grace-period thread's existing call
to trc_del_holdout(), thus eliminating that particular class of
use-after-free errors.
Reported-by: "Xu, Yanfei" <yanfei.xu@windriver.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
kernel/rcu/tasks.h | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h
index 350ebf5051f9..71e9d625371a 100644
--- a/kernel/rcu/tasks.h
+++ b/kernel/rcu/tasks.h
@@ -908,10 +908,9 @@ static bool trc_inspect_reader(struct task_struct *t, void *arg)
in_qs = likely(!t->trc_reader_nesting);
}
- // Mark as checked. Because this is called from the grace-period
- // kthread, also remove the task from the holdout list.
+ // Mark as checked so that the grace-period kthread will
+ // remove it from the holdout list.
t->trc_reader_checked = true;
- trc_del_holdout(t);
if (in_qs)
return true; // Already in quiescent state, done!!!
--
2.30.2
next prev parent reply other threads:[~2021-07-23 3:57 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-23 3:57 [PATCH AUTOSEL 5.13 01/19] net/802/mrp: fix memleak in mrp_request_join() Sasha Levin
2021-07-23 3:57 ` [PATCH AUTOSEL 5.13 02/19] net/802/garp: fix memleak in garp_request_join() Sasha Levin
2021-07-23 3:57 ` [PATCH AUTOSEL 5.13 03/19] net: annotate data race around sk_ll_usec Sasha Levin
2021-07-23 3:57 ` [PATCH AUTOSEL 5.13 04/19] sctp: move 198 addresses from unusable to private scope Sasha Levin
2021-07-23 3:57 ` Sasha Levin [this message]
2021-07-23 3:57 ` [PATCH AUTOSEL 5.13 06/19] rcu-tasks: Don't delete holdouts within trc_wait_for_one_reader() Sasha Levin
2021-07-23 3:57 ` [PATCH AUTOSEL 5.13 07/19] ipv6: allocate enough headroom in ip6_finish_output2() Sasha Levin
2021-07-23 6:03 ` Vasily Averin
2021-07-28 14:07 ` Sasha Levin
2021-07-23 3:57 ` [PATCH AUTOSEL 5.13 08/19] nvme-pci: fix multiple races in nvme_setup_io_queues Sasha Levin
2021-07-23 3:57 ` [PATCH AUTOSEL 5.13 09/19] sfc: ensure correct number of XDP queues Sasha Levin
2021-07-23 10:12 ` Íñigo Huguet
2021-07-23 10:18 ` Íñigo Huguet
2021-07-23 3:57 ` [PATCH AUTOSEL 5.13 10/19] drm/ttm: add a check against null pointer dereference Sasha Levin
2021-07-23 3:57 ` [PATCH AUTOSEL 5.13 11/19] hfs: add missing clean-up in hfs_fill_super Sasha Levin
2021-07-23 3:57 ` [PATCH AUTOSEL 5.13 12/19] hfs: fix high memory mapping in hfs_bnode_read Sasha Levin
2021-07-23 3:57 ` [PATCH AUTOSEL 5.13 13/19] hfs: add lock nesting notation to hfs_find_init Sasha Levin
2021-07-23 3:57 ` [PATCH AUTOSEL 5.13 14/19] firmware: arm_scmi: Fix possible scmi_linux_errmap buffer overflow Sasha Levin
2021-07-23 3:57 ` [PATCH AUTOSEL 5.13 15/19] firmware: arm_scmi: Fix range check for the maximum number of pending messages Sasha Levin
2021-07-23 3:57 ` [PATCH AUTOSEL 5.13 16/19] cifs: fix the out of range assignment to bit fields in parse_server_interfaces Sasha Levin
2021-07-23 3:57 ` [PATCH AUTOSEL 5.13 17/19] iomap: remove the length variable in iomap_seek_data Sasha Levin
2021-07-23 3:57 ` [PATCH AUTOSEL 5.13 18/19] iomap: remove the length variable in iomap_seek_hole Sasha Levin
2021-07-23 3:57 ` [PATCH AUTOSEL 5.13 19/19] ARM: dts: versatile: Fix up interrupt controller node names Sasha Levin
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=20210723035721.531372-5-sashal@kernel.org \
--to=sashal@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=paulmck@kernel.org \
--cc=rcu@vger.kernel.org \
--cc=stable@vger.kernel.org \
--cc=yanfei.xu@windriver.com \
/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).