[patch 2/2] r/o bind mounts: Accept passing a mnt NULL pointer to mnt_drop_write()

[Jan Blunck <jblunck@suse.de>]

In case of somebody opens a file with dentry_open(dentry, NULL, ...) we don't
want to stumble on the NULL pointer mnt in struct file.

Signed-off-by: Jan Blunck <jblunck@suse.de>
---
 fs/namespace.c |    3 +++
 1 file changed, 3 insertions(+)

Index: b/fs/namespace.c
===================================================================
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -253,6 +253,9 @@ void mnt_drop_write(struct vfsmount *mnt
 	int must_check_underflow = 0;
 	struct mnt_writer *cpu_writer;
 
+	if (!mnt)
+		return;
+
 	cpu_writer = &get_cpu_var(mnt_writers);
 	spin_lock(&cpu_writer->lock);
 

-- 

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