Add security hooks that will allow an LSM to rule on whether or not a watch may be set on a mount or on a superblock. More than one hook is required as the watches watch different types of object.
Signed-off-by: David Howells <[email protected]> cc: Casey Schaufler <[email protected]> cc: Stephen Smalley <[email protected]> cc: [email protected] --- include/linux/lsm_hooks.h | 16 ++++++++++++++++ include/linux/security.h | 10 ++++++++++ security/security.c | 10 ++++++++++ 3 files changed, 36 insertions(+) diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h index 5fe387d35990..3a4d7a260572 100644 --- a/include/linux/lsm_hooks.h +++ b/include/linux/lsm_hooks.h @@ -1433,6 +1433,18 @@ * from devices (as a global set). * @watch: The watch object * + * @watch_mount: + * Check to see if a process is allowed to watch for mount topology change + * notifications on a mount subtree. + * @watch: The watch object + * @path: The root of the subtree to watch. + * + * @watch_sb: + * Check to see if a process is allowed to watch for event notifications + * from a superblock. + * @watch: The watch object + * @sb: The superblock to watch. + * * @post_notification: * Check to see if a watch notification can be posted to a particular * queue. @@ -1721,6 +1733,8 @@ union security_list_options { #ifdef CONFIG_WATCH_QUEUE int (*watch_key)(struct watch *watch, struct key *key); int (*watch_devices)(struct watch *watch); + int (*watch_mount)(struct watch *watch, struct path *path); + int (*watch_sb)(struct watch *watch, struct super_block *sb); int (*post_notification)(const struct cred *w_cred, const struct cred *cred, struct watch_notification *n); @@ -2007,6 +2021,8 @@ struct security_hook_heads { #ifdef CONFIG_WATCH_QUEUE struct hlist_head watch_key; struct hlist_head watch_devices; + struct hlist_head watch_mount; + struct hlist_head watch_sb; struct hlist_head post_notification; #endif /* CONFIG_WATCH_QUEUE */ #ifdef CONFIG_SECURITY_NETWORK diff --git a/include/linux/security.h b/include/linux/security.h index 8a9645472232..74ec6d41eca5 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -401,6 +401,8 @@ int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen); #ifdef CONFIG_WATCH_QUEUE int security_watch_key(struct watch *watch, struct key *key); int security_watch_devices(struct watch *watch); +int security_watch_mount(struct watch *watch, struct path *path); +int security_watch_sb(struct watch *watch, struct super_block *sb); int security_post_notification(const struct cred *w_cred, const struct cred *cred, struct watch_notification *n); @@ -1233,6 +1235,14 @@ static inline int security_watch_devices(struct watch *watch) { return 0; } +static inline int security_watch_mount(struct watch *watch, struct path *path) +{ + return 0; +} +static inline int security_watch_sb(struct watch *watch, struct super_block *sb) +{ + return 0; +} static inline int security_post_notification(const struct cred *w_cred, const struct cred *cred, struct watch_notification *n) diff --git a/security/security.c b/security/security.c index 1390fb1203e4..37fec6cec905 100644 --- a/security/security.c +++ b/security/security.c @@ -1940,6 +1940,16 @@ int security_watch_devices(struct watch *watch) return call_int_hook(watch_devices, 0, watch); } +int security_watch_mount(struct watch *watch, struct path *path) +{ + return call_int_hook(watch_mount, 0, watch, path); +} + +int security_watch_sb(struct watch *watch, struct super_block *sb) +{ + return call_int_hook(watch_sb, 0, watch, sb); +} + int security_post_notification(const struct cred *w_cred, const struct cred *cred, struct watch_notification *n)
