diff options
| author | Eric W. Biederman <ebiederm@xmission.com> | 2015-01-07 08:10:09 -0600 |
|---|---|---|
| committer | Eric W. Biederman <ebiederm@xmission.com> | 2015-07-01 10:36:35 -0500 |
| commit | ceeb0e5d39fcdf4dca2c997bf225c7fc49200b37 (patch) | |
| tree | 8e005dec00f79b8176f42070c176c43b3e3bf030 /fs/namespace.c | |
| parent | 8c6cf9cc829fcd0b179b59f7fe288941d0e31108 (diff) | |
| download | lwn-ceeb0e5d39fcdf4dca2c997bf225c7fc49200b37.tar.gz lwn-ceeb0e5d39fcdf4dca2c997bf225c7fc49200b37.zip | |
vfs: Ignore unlocked mounts in fs_fully_visible
Limit the mounts fs_fully_visible considers to locked mounts.
Unlocked can always be unmounted so considering them adds hassle
but no security benefit.
Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Diffstat (limited to 'fs/namespace.c')
| -rw-r--r-- | fs/namespace.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/fs/namespace.c b/fs/namespace.c index 63b9806235e6..8c7b8e0941b9 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -3205,11 +3205,15 @@ static bool fs_fully_visible(struct file_system_type *type, int *new_mnt_flags) ((mnt->mnt.mnt_flags & MNT_ATIME_MASK) != (new_flags & MNT_ATIME_MASK))) continue; - /* This mount is not fully visible if there are any child mounts - * that cover anything except for empty directories. + /* This mount is not fully visible if there are any + * locked child mounts that cover anything except for + * empty directories. */ list_for_each_entry(child, &mnt->mnt_mounts, mnt_child) { struct inode *inode = child->mnt_mountpoint->d_inode; + /* Only worry about locked mounts */ + if (!(mnt->mnt.mnt_flags & MNT_LOCKED)) + continue; if (!S_ISDIR(inode->i_mode)) goto next; if (inode->i_nlink > 2) |