| Message ID | 1474663238-22134-7-git-send-email-jann@thejh.net (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
diff --git a/kernel/ptrace.c b/kernel/ptrace.c index 29ace11..17c2245 100644 --- a/kernel/ptrace.c +++ b/kernel/ptrace.c @@ -225,6 +225,9 @@ static int __ptrace_may_access(struct task_struct *task, unsigned int mode, kuid_t caller_uid; kgid_t caller_gid; + WARN_ON(!mutex_is_locked(&task->signal->cred_guard_mutex) && + !mutex_is_locked(&task->signal->cred_guard_light)); + if (!(mode & PTRACE_MODE_FSCREDS) == !(mode & PTRACE_MODE_REALCREDS)) { WARN(1, "denying ptrace access check without PTRACE_MODE_*CREDS\n"); return -EPERM;
If neither of those locks is taken during a ptrace_may_access() call, that is a strong indicator for a security bug where post-execve process properties can be leaked by racing with execve(). Signed-off-by: Jann Horn <jann@thejh.net> --- kernel/ptrace.c | 3 +++ 1 file changed, 3 insertions(+)