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From: Nick Dyer <nick.dyer@itdev.co.uk>
To: gregkh@linuxfoundation.org
Cc: linux-kernel@vger.kernel.org, Nick Dyer <nick.dyer@itdev.co.uk>
Subject: [PATCH] Fix null pointer dereference caused by sysfs_notify on binary attribute
Date: Thu,  6 Jun 2013 10:45:20 +0100	[thread overview]
Message-ID: <1370511920-8628-1-git-send-email-nick.dyer@itdev.co.uk> (raw)

It would be nice to have this work as expected but for now this is a minimal
fix to prevent the kernel panic.

Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>
---
 fs/sysfs/file.c |   10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index 602f56d..976819b 100644
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -449,10 +449,12 @@ void sysfs_notify_dirent(struct sysfs_dirent *sd)
 
 	spin_lock_irqsave(&sysfs_open_dirent_lock, flags);
 
-	od = sd->s_attr.open;
-	if (od) {
-		atomic_inc(&od->event);
-		wake_up_interruptible(&od->poll);
+	if (sd->s_attr) {
+		od = sd->s_attr.open;
+		if (od) {
+			atomic_inc(&od->event);
+			wake_up_interruptible(&od->poll);
+		}
 	}
 
 	spin_unlock_irqrestore(&sysfs_open_dirent_lock, flags);
-- 
1.7.10.4


             reply	other threads:[~2013-06-06  9:46 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-06-06  9:45 Nick Dyer [this message]
2013-06-06 15:26 ` Greg KH
2013-06-06 15:36   ` Nick Dyer
2013-06-06 19:37 ` [PATCH] sysfs: " Greg KH
2013-06-07 14:45   ` [PATCH V2] sysfs_notify is only possible on file attributes Nick Dyer

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