All of lore.kernel.org
 help / color / mirror / Atom feed
From: Dan Carpenter <dan.carpenter@oracle.com>
To: Tejun Heo <tj@kernel.org>, Sean Fu <fxinrong@gmail.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>,
	linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org
Subject: [PATCH] workqueue: Fix an use after free in init_rescuer()
Date: Fri, 08 May 2020 15:07:40 +0000	[thread overview]
Message-ID: <20200508150740.GA415175@mwanda> (raw)

We need to preserve error code before freeing "rescuer".

Fixes: f187b6974f6df ("workqueue: Use IS_ERR and PTR_ERR instead of PTR_ERR_OR_ZERO.")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
Another option would be to just revert the original commit.

 kernel/workqueue.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index ddf0537dce140..10ed8d761e0b7 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -4197,6 +4197,7 @@ static int wq_clamp_max_active(int max_active, unsigned int flags,
 static int init_rescuer(struct workqueue_struct *wq)
 {
 	struct worker *rescuer;
+	int ret;
 
 	if (!(wq->flags & WQ_MEM_RECLAIM))
 		return 0;
@@ -4208,8 +4209,9 @@ static int init_rescuer(struct workqueue_struct *wq)
 	rescuer->rescue_wq = wq;
 	rescuer->task = kthread_create(rescuer_thread, rescuer, "%s", wq->name);
 	if (IS_ERR(rescuer->task)) {
+		ret = PTR_ERR(rescuer->task);
 		kfree(rescuer);
-		return PTR_ERR(rescuer->task);
+		return ret;
 	}
 
 	wq->rescuer = rescuer;
-- 
2.26.2

WARNING: multiple messages have this Message-ID (diff)
From: Dan Carpenter <dan.carpenter@oracle.com>
To: Tejun Heo <tj@kernel.org>, Sean Fu <fxinrong@gmail.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>,
	linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org
Subject: [PATCH] workqueue: Fix an use after free in init_rescuer()
Date: Fri, 8 May 2020 18:07:40 +0300	[thread overview]
Message-ID: <20200508150740.GA415175@mwanda> (raw)

We need to preserve error code before freeing "rescuer".

Fixes: f187b6974f6df ("workqueue: Use IS_ERR and PTR_ERR instead of PTR_ERR_OR_ZERO.")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
Another option would be to just revert the original commit.

 kernel/workqueue.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index ddf0537dce140..10ed8d761e0b7 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -4197,6 +4197,7 @@ static int wq_clamp_max_active(int max_active, unsigned int flags,
 static int init_rescuer(struct workqueue_struct *wq)
 {
 	struct worker *rescuer;
+	int ret;
 
 	if (!(wq->flags & WQ_MEM_RECLAIM))
 		return 0;
@@ -4208,8 +4209,9 @@ static int init_rescuer(struct workqueue_struct *wq)
 	rescuer->rescue_wq = wq;
 	rescuer->task = kthread_create(rescuer_thread, rescuer, "%s", wq->name);
 	if (IS_ERR(rescuer->task)) {
+		ret = PTR_ERR(rescuer->task);
 		kfree(rescuer);
-		return PTR_ERR(rescuer->task);
+		return ret;
 	}
 
 	wq->rescuer = rescuer;
-- 
2.26.2


             reply	other threads:[~2020-05-08 15:07 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-05-08 15:07 Dan Carpenter [this message]
2020-05-08 15:07 ` [PATCH] workqueue: Fix an use after free in init_rescuer() Dan Carpenter
2020-05-10 10:33 ` Lai Jiangshan
2020-05-10 10:33   ` Lai Jiangshan
2020-05-11 14:27 ` Tejun Heo
2020-05-11 14:27   ` Tejun Heo

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=20200508150740.GA415175@mwanda \
    --to=dan.carpenter@oracle.com \
    --cc=fxinrong@gmail.com \
    --cc=jiangshanlai@gmail.com \
    --cc=kernel-janitors@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=tj@kernel.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.