From: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> [ Upstream commit 7e96c1b0e0f495c5a7450dc4aa7c9a24ba4305bd ] 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. Cc: stable@xxxxxxxxxxxxxxx Reported-by: Eric Windisch <ewindisch@xxxxxxxxxx> Signed-off-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> Signed-off-by: Sasha Levin <sasha.levin@xxxxxxxxxx> --- fs/namespace.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/namespace.c b/fs/namespace.c index 07ba424..64837e3 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -3137,6 +3137,12 @@ bool fs_fully_visible(struct file_system_type *type) if (mnt->mnt.mnt_sb->s_type != type) continue; + /* 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. */ -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html