diff options
| author | Mickaël Salaün <mic@digikod.net> | 2026-09-18 20:50:28 +0200 |
|---|---|---|
| committer | Mickaël Salaün <mic@digikod.net> | 2026-09-20 11:08:03 +0200 |
| commit | 7ad69ac63315506e2091bf46d5c96c49f6ce439e (patch) | |
| tree | 755aa6be72b9fd53deee8454860324abbab3e025 /include/trace | |
| parent | 98b04ab00f0e738d69bd718228db55483a911b7a (diff) | |
landlock: Report the actual ptrace tracer
The ptrace denial callback identifies only the tracee. Current is the
tracer during hook_ptrace_access_check(), but it is the tracee during
PTRACE_TRACEME, where the parent is the actual tracer. A consumer
therefore cannot infer both parties from the existing arguments.
Append the actual tracer task to the typed-BPF callback: current for
hook_ptrace_access_check() and parent for hook_ptrace_traceme(). Carry
it with the tracee domain ID in a private ptrace context. Both hooks
keep the selected tasks alive through synchronous dispatch, so no extra
task reference is needed.
Keep the tracefs record unchanged. The new context is available only to
typed BPF, while same_exec continues to describe the tracer that owns
the denying policy.
Cc: Günther Noack <gnoack@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Fixes: bb91730f16c0 ("landlock: Add tracepoints for ptrace and scope denials")
Link: https://patch.msgid.link/20260918185036.608651-6-mic@digikod.net
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Diffstat (limited to 'include/trace')
| -rw-r--r-- | include/trace/events/landlock.h | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/include/trace/events/landlock.h b/include/trace/events/landlock.h index a982a7cfa881..8c6ebf958d66 100644 --- a/include/trace/events/landlock.h +++ b/include/trace/events/landlock.h @@ -295,6 +295,8 @@ static inline const char *__trace_landlock_print_layers( * the two parties without kernel-internal state. The ID is a scalar * snapshot, not a live domain pointer that could dangle: an optional * relational referent is a scalar (0 sentinel), not a nullable pointer. + * For ptrace, same_exec instead describes the tracer, even for + * PTRACE_TRACEME, and may differ from the current task. * * Blocker fields * ~~~~~~~~~~~~~~ @@ -875,12 +877,14 @@ TRACE_EVENT(landlock_deny_access_net, * * @hierarchy: Denying domain's hierarchy node (never NULL); its id is the * domain field. - * @same_exec: Whether the current task entered the denying domain itself. + * @same_exec: Whether the tracer entered the denying domain itself. * @logged: The domain's audit-logging decision for this denial. * @tracee_domain_id: The tracee's Landlock domain ID, or 0 if the tracee * is unsandboxed. * @tracee: The target task ptrace acted on (never NULL). tracee_pid is * the init-namespace TGID (like audit's opid). + * @tracer: The tracer or proposed tracer (never NULL); for PTRACE_TRACEME + * this is the parent, not the syscall caller. * * Emitted when a Landlock domain denies a ptrace operation. */ @@ -888,9 +892,10 @@ TRACE_EVENT(landlock_deny_ptrace, TP_PROTO(const struct landlock_hierarchy *hierarchy, bool same_exec, bool logged, u64 tracee_domain_id, - const struct task_struct *tracee), + const struct task_struct *tracee, + const struct task_struct *tracer), - TP_ARGS(hierarchy, same_exec, logged, tracee_domain_id, tracee), + TP_ARGS(hierarchy, same_exec, logged, tracee_domain_id, tracee, tracer), TP_STRUCT__entry( __field( u64, domain_id ) |