linux-kernel - [PATCH v3] xen/debugfs: Check debugfs initialization before using it

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <1386583012-506-1-git-send-email-ethan.kernel@gmail.com>
Date:	Mon,  9 Dec 2013 17:56:52 +0800
From:	Ethan Zhao <ethan.kernel@...il.com>
To:	gregkh@...uxfoundation.org, konrad.wilk@...cle.com,
	raghavendra.kt@...ux.vnet.ibm.com
Cc:	linux-kernel@...r.kernel.org, "ethan.zhao" <ethan.kernel@...il.com>
Subject: [PATCH v3] xen/debugfs: Check debugfs initialization before using it

From: "ethan.zhao" <ethan.kernel@...il.com>

Should check debugfs initialization with debugfs_initialized() before using it,
Because if it isn't initialized, the return value of fake debugfs_create_dir() etc
functions would be ERR_PTR(-ENODEV), checking with NULL will not work.

V3: add warning message when debugfs not configured or disabled.

Signed-off-by: ethan.zhao <ethan.kernel@...il.com>
---
 arch/x86/xen/debugfs.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/x86/xen/debugfs.c b/arch/x86/xen/debugfs.c
index c8377fb..85c0e0e 100644
--- a/arch/x86/xen/debugfs.c
+++ b/arch/x86/xen/debugfs.c
@@ -9,12 +9,18 @@ static struct dentry *d_xen_debug;
 
 struct dentry * __init xen_init_debugfs(void)
 {
+	if (!debugfs_initialized()) {
+		d_xen_debug = NULL;
+		goto nodebugfs;
+	}
+
 	if (!d_xen_debug) {
 		d_xen_debug = debugfs_create_dir("xen", NULL);
 
 		if (!d_xen_debug)
 			pr_warning("Could not create 'xen' debugfs directory\n");
 	}
+nodebugfs:
 
 	return d_xen_debug;
 }
-- 
1.8.3.4 (Apple Git-47)

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/