[PATCH RFC v2 2/8] security: Add hooks to rule on setting a watch for superblock
From: Gabriel Krisman Bertazi <hidden>
Date: 2020-11-11 21:52:37
Also in:
linux-fsdevel
Subsystem:
security subsystem, the rest · Maintainers:
Paul Moore, James Morris, "Serge E. Hallyn", Linus Torvalds
From: David Howells <dhowells@redhat.com> Add security hooks that will allow an LSM to rule on whether or not a watch may be set for a supperblock. Signed-off-by: David Howells <dhowells@redhat.com> [Drop mount and key changes. Rebase to mainline] Signed-off-by: Gabriel Krisman Bertazi <redacted> --- include/linux/lsm_hook_defs.h | 1 + include/linux/lsm_hooks.h | 4 ++++ include/linux/security.h | 13 +++++++++++++ security/security.c | 6 ++++++ 4 files changed, 24 insertions(+)
diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h
index 32a940117e7a..8fa8533598bc 100644
--- a/include/linux/lsm_hook_defs.h
+++ b/include/linux/lsm_hook_defs.h@@ -261,6 +261,7 @@ LSM_HOOK(int, 0, inode_getsecctx, struct inode *inode, void **ctx, #if defined(CONFIG_SECURITY) && defined(CONFIG_WATCH_QUEUE) LSM_HOOK(int, 0, post_notification, const struct cred *w_cred, const struct cred *cred, struct watch_notification *n) +LSM_HOOK(int, 0, watch_sb, struct super_block *sb) #endif /* CONFIG_SECURITY && CONFIG_WATCH_QUEUE */ #if defined(CONFIG_SECURITY) && defined(CONFIG_KEY_NOTIFICATIONS)
diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index c503f7ab8afb..11197bf167d3 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h@@ -1475,6 +1475,10 @@ * @w_cred: The credentials of the whoever set the watch. * @cred: The event-triggerer's credentials * @n: The notification being posted + * @watch_sb: + * Check to see if a process is allowed to watch for event notifications + * from a superblock. + * @sb: The superblock to watch. * * @watch_key: * Check to see if a process is allowed to watch for event notifications
diff --git a/include/linux/security.h b/include/linux/security.h
index bc2725491560..078e11a8872a 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h@@ -456,6 +456,11 @@ int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen); int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen); int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen); int security_locked_down(enum lockdown_reason what); + +#ifdef CONFIG_WATCH_QUEUE +int security_watch_sb(struct super_block *sb); +#endif /* CONFIG_WATCH_QUEUE */ + #else /* CONFIG_SECURITY */ static inline int call_blocking_lsm_notifier(enum lsm_event event, void *data)
@@ -1304,6 +1309,14 @@ static inline int security_locked_down(enum lockdown_reason what) { return 0; } + +#ifdef CONFIG_WATCH_QUEUE +static inline int security_watch_sb(struct super_block *sb) +{ + return 0; +} +#endif /* CONFIG_WATCH_QUEUE */ + #endif /* CONFIG_SECURITY */ #if defined(CONFIG_SECURITY) && defined(CONFIG_WATCH_QUEUE)
diff --git a/security/security.c b/security/security.c
index a28045dc9e7f..a23a972063cd 100644
--- a/security/security.c
+++ b/security/security.c@@ -2074,6 +2074,12 @@ int security_post_notification(const struct cred *w_cred, { return call_int_hook(post_notification, 0, w_cred, cred, n); } + +int security_watch_sb(struct super_block *sb) +{ + return call_int_hook(watch_sb, 0, sb); +} + #endif /* CONFIG_WATCH_QUEUE */ #ifdef CONFIG_KEY_NOTIFICATIONS
--
2.29.2