linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Hangyu Hua <hbh25y@gmail.com>
To: fbarrat@linux.ibm.com, ajd@linux.ibm.com, arnd@arndb.de,
	gregkh@linuxfoundation.org, mpe@ellerman.id.au,
	alastair@d-silva.org
Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org,
	Hangyu Hua <hbh25y@gmail.com>
Subject: [PATCH] misc: ocxl: fix possible double free in ocxl_file_register_afu
Date: Mon, 18 Apr 2022 16:57:58 +0800	[thread overview]
Message-ID: <20220418085758.38145-1-hbh25y@gmail.com> (raw)

info_release() will be called in device_unregister() when info->dev's
reference count is 0. So there is no need to call ocxl_afu_put() and
kfree() again.

Fix this by adding free_minor() and return to err_unregister error path.

Fixes: 75ca758adbaf ("ocxl: Create a clear delineation between ocxl backend & frontend")
Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
---
 drivers/misc/ocxl/file.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/misc/ocxl/file.c b/drivers/misc/ocxl/file.c
index d881f5e40ad9..6777c419a8da 100644
--- a/drivers/misc/ocxl/file.c
+++ b/drivers/misc/ocxl/file.c
@@ -556,7 +556,9 @@ int ocxl_file_register_afu(struct ocxl_afu *afu)
 
 err_unregister:
 	ocxl_sysfs_unregister_afu(info); // safe to call even if register failed
+	free_minor(info);
 	device_unregister(&info->dev);
+	return rc;
 err_put:
 	ocxl_afu_put(afu);
 	free_minor(info);
-- 
2.25.1


             reply	other threads:[~2022-04-18  8:58 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-04-18  8:57 Hangyu Hua [this message]
2022-04-19  9:09 ` [PATCH] misc: ocxl: fix possible double free in ocxl_file_register_afu Frederic Barrat
2022-04-19 11:02   ` Hangyu Hua
2022-04-20 22:54 ` Michael Ellerman
2022-04-21  2:35   ` Hangyu Hua
2022-04-21  7:51   ` Frederic Barrat
2022-04-22  9:36     ` Michael Ellerman
2022-05-15 10:12 ` Michael Ellerman

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=20220418085758.38145-1-hbh25y@gmail.com \
    --to=hbh25y@gmail.com \
    --cc=ajd@linux.ibm.com \
    --cc=alastair@d-silva.org \
    --cc=arnd@arndb.de \
    --cc=fbarrat@linux.ibm.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=mpe@ellerman.id.au \
    /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).