path: root/fs
diff options
authorEric W. Biederman <ebiederm@xmission.com>2015-05-08 16:36:50 -0500
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2015-05-17 09:53:49 -0700
commit4c0b6322754c01a0424b0a5d7e8e0b964781fcc0 (patch)
treec251129dd78dabd938a126a803d204979cc27917 /fs
parentbe323587d27b8bfe18681ad98d941256bfdd8248 (diff)
mnt: Fix fs_fully_visible to verify the root directory is visible
commit 7e96c1b0e0f495c5a7450dc4aa7c9a24ba4305bd upstream. This fixes a dumb bug in fs_fully_visible that allows proc or sys to be mounted if there is a bind mount of part of /proc/ or /sys/ visible. Reported-by: Eric Windisch <ewindisch@docker.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs')
1 files changed, 6 insertions, 0 deletions
diff --git a/fs/namespace.c b/fs/namespace.c
index 039f3802d70e..2faa7eacb62b 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -3025,6 +3025,12 @@ bool fs_fully_visible(struct file_system_type *type)
if (mnt->mnt.mnt_sb->s_type != type)
+ /* This mount is not fully visible if it's root directory
+ * is not the root directory of the filesystem.
+ */
+ if (mnt->mnt.mnt_root != mnt->mnt.mnt_sb->s_root)
+ continue;
/* This mount is not fully visible if there are any child mounts
* that cover anything except for empty directories.