diff options
author | Eric W. Biederman <ebiederm@xmission.com> | 2015-05-08 23:36:50 +0200 |
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committer | Eric W. Biederman <ebiederm@xmission.com> | 2015-05-09 18:55:50 +0200 |
commit | 7e96c1b0e0f495c5a7450dc4aa7c9a24ba4305bd (patch) | |
tree | 359383086b15aa2d27e543d51865886d51d2bb23 /fs/namespace.c | |
parent | Linux 4.1-rc1 (diff) | |
download | linux-7e96c1b0e0f495c5a7450dc4aa7c9a24ba4305bd.tar.xz linux-7e96c1b0e0f495c5a7450dc4aa7c9a24ba4305bd.zip |
mnt: Fix fs_fully_visible to verify the root directory is visible
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@vger.kernel.org
Reported-by: Eric Windisch <ewindisch@docker.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Diffstat (limited to 'fs/namespace.c')
-rw-r--r-- | fs/namespace.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/fs/namespace.c b/fs/namespace.c index 1f4f9dac6e5a..1b9e11167bae 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -3179,6 +3179,12 @@ 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. */ |