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| author | Eric W. Biederman <ebiederm@xmission.com> | 2013-03-30 01:35:18 -0700 |
|---|---|---|
| committer | Eric W. Biederman <ebiederm@xmission.com> | 2013-08-26 18:42:15 -0700 |
| commit | 4ce5d2b1a8fde84c0eebe70652cf28b9beda6b4e (patch) | |
| tree | 08fa563457c4264fe48355e8d28c216c9a11664b /fs/pnode.h | |
| parent | 21e851943e31022731cd5fad386ca8fb552dbe64 (diff) | |
| download | lwn-4ce5d2b1a8fde84c0eebe70652cf28b9beda6b4e.tar.gz lwn-4ce5d2b1a8fde84c0eebe70652cf28b9beda6b4e.zip | |
vfs: Don't copy mount bind mounts of /proc/<pid>/ns/mnt between namespaces
Don't copy bind mounts of /proc/<pid>/ns/mnt between namespaces.
These files hold references to a mount namespace and copying them
between namespaces could result in a reference counting loop.
The current mnt_ns_loop test prevents loops on the assumption that
mounts don't cross between namespaces. Unfortunately unsharing a
mount namespace and shared substrees can both cause mounts to
propogate between mount namespaces.
Add two flags CL_COPY_UNBINDABLE and CL_COPY_MNT_NS_FILE are added to
control this behavior, and CL_COPY_ALL is redefined as both of them.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Diffstat (limited to 'fs/pnode.h')
| -rw-r--r-- | fs/pnode.h | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/fs/pnode.h b/fs/pnode.h index b091445c1c4a..59e7eda1851e 100644 --- a/fs/pnode.h +++ b/fs/pnode.h @@ -19,11 +19,14 @@ #define CL_EXPIRE 0x01 #define CL_SLAVE 0x02 -#define CL_COPY_ALL 0x04 +#define CL_COPY_UNBINDABLE 0x04 #define CL_MAKE_SHARED 0x08 #define CL_PRIVATE 0x10 #define CL_SHARED_TO_SLAVE 0x20 #define CL_UNPRIVILEGED 0x40 +#define CL_COPY_MNT_NS_FILE 0x80 + +#define CL_COPY_ALL (CL_COPY_UNBINDABLE | CL_COPY_MNT_NS_FILE) static inline void set_mnt_shared(struct mount *mnt) { |