diff options
| author | Mickaël Salaün <mic@digikod.net> | 2025-03-20 20:06:56 +0100 |
|---|---|---|
| committer | Mickaël Salaün <mic@digikod.net> | 2025-03-26 13:59:37 +0100 |
| commit | 79625f1b3a3df63d3289a0781fdf121bc42966f7 (patch) | |
| tree | dfa07c48a247c97196ffab5256cafeea8f82bc0e /security/landlock/task.c | |
| parent | 8d20efa9dc6cb471b71fd388923753f767ab13ce (diff) | |
landlock: Prepare to use credential instead of domain for fowner
This cosmetic change is needed for audit support, specifically to be
able to filter according to cross-execution boundaries.
struct landlock_file_security's size stay the same for now but it will
increase with struct landlock_cred_security's size.
Only save Landlock domain in hook_file_set_fowner() if the current
domain has LANDLOCK_SCOPE_SIGNAL, which was previously done for each
hook_file_send_sigiotask() calls. This should improve a bit
performance.
Replace hardcoded LANDLOCK_SCOPE_SIGNAL with the signal_scope.scope
variable.
Use scoped guards for RCU read-side critical sections.
Cc: Günther Noack <gnoack@google.com>
Link: https://lore.kernel.org/r/20250320190717.2287696-8-mic@digikod.net
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Diffstat (limited to 'security/landlock/task.c')
| -rw-r--r-- | security/landlock/task.c | 25 |
1 files changed, 16 insertions, 9 deletions
diff --git a/security/landlock/task.c b/security/landlock/task.c index e3ad7403b532..b89ab9a904eb 100644 --- a/security/landlock/task.c +++ b/security/landlock/task.c @@ -302,22 +302,29 @@ static int hook_task_kill(struct task_struct *const p, static int hook_file_send_sigiotask(struct task_struct *tsk, struct fown_struct *fown, int signum) { - const struct landlock_ruleset *dom; + const struct landlock_cred_security *subject; bool is_scoped = false; /* Lock already held by send_sigio() and send_sigurg(). */ lockdep_assert_held(&fown->lock); - dom = landlock_get_applicable_domain( - landlock_file(fown->file)->fown_domain, signal_scope); + subject = &landlock_file(fown->file)->fown_subject; - /* Quick return for unowned socket. */ - if (!dom) + /* + * Quick return for unowned socket. + * + * subject->domain has already been filtered when saved by + * hook_file_set_fowner(), so there is no need to call + * landlock_get_applicable_subject() here. + */ + if (!subject->domain) return 0; - rcu_read_lock(); - is_scoped = domain_is_scoped(dom, landlock_get_task_domain(tsk), - LANDLOCK_SCOPE_SIGNAL); - rcu_read_unlock(); + scoped_guard(rcu) + { + is_scoped = domain_is_scoped(subject->domain, + landlock_get_task_domain(tsk), + signal_scope.scope); + } if (is_scoped) return -EPERM; |