From: Xiyu Yang <xiyuyang19@fudan.edu.cn>
To: Rob Springer <rspringer@google.com>,
Todd Poynor <toddpoynor@google.com>,
Ben Chan <benchan@chromium.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org
Cc: Xin Tan <tanxin.ctf@gmail.com>,
yuanxzhang@fudan.edu.cn, kjlu@umn.edu,
Xiyu Yang <xiyuyang19@fudan.edu.cn>
Subject: [PATCH] staging: gasket: Fix mapping refcnt leak when put attribute fails
Date: Thu, 23 Apr 2020 13:14:55 +0800 [thread overview]
Message-ID: <1587618895-13660-1-git-send-email-xiyuyang19@fudan.edu.cn> (raw)
gasket_sysfs_put_attr() invokes get_mapping(), which returns a reference
of the specified gasket_sysfs_mapping object to "mapping" with increased
refcnt.
When gasket_sysfs_put_attr() returns, local variable "mapping" becomes
invalid, so the refcount should be decreased to keep refcount balanced.
The reference counting issue happens in one path of
gasket_sysfs_put_attr(). When mapping attribute is unknown, the function
forgets to decrease the refcnt increased by get_mapping(), causing a
refcnt leak.
Fix this issue by calling put_mapping() when put attribute fails due to
unknown attribute.
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
---
drivers/staging/gasket/gasket_sysfs.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/staging/gasket/gasket_sysfs.c b/drivers/staging/gasket/gasket_sysfs.c
index a2d67c28f530..f24edc38c27b 100644
--- a/drivers/staging/gasket/gasket_sysfs.c
+++ b/drivers/staging/gasket/gasket_sysfs.c
@@ -340,6 +340,7 @@ void gasket_sysfs_put_attr(struct device *device,
dev_err(device, "Unable to put unknown attribute: %s\n",
attr->attr.attr.name);
+ put_mapping(mapping);
}
EXPORT_SYMBOL(gasket_sysfs_put_attr);
--
2.7.4
_______________________________________________
devel mailing list
devel@linuxdriverproject.org
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
reply other threads:[~2020-04-23 5:15 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
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=1587618895-13660-1-git-send-email-xiyuyang19@fudan.edu.cn \
--to=xiyuyang19@fudan.edu.cn \
--cc=benchan@chromium.org \
--cc=devel@driverdev.osuosl.org \
--cc=gregkh@linuxfoundation.org \
--cc=kjlu@umn.edu \
--cc=linux-kernel@vger.kernel.org \
--cc=rspringer@google.com \
--cc=tanxin.ctf@gmail.com \
--cc=toddpoynor@google.com \
--cc=yuanxzhang@fudan.edu.cn \
/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).