Debugging code for verbose output to aid in development. --- fs/proc/base.c | 10 ++++++++++ kernel/auditsc.c | 16 ++++++++++++++++ 2 files changed, 26 insertions(+) diff --git a/fs/proc/base.c b/fs/proc/base.c index f66d1e2..63d1ca4 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -1309,9 +1309,13 @@ static ssize_t proc_containerid_read(struct file *file, char __user *buf, char tmpbuf[TMPBUFLEN*2]; if (!task) + { + pr_info("no inode owner"); return -ESRCH; + } length = scnprintf(tmpbuf, TMPBUFLEN*2, "%llu", audit_get_containerid(task)); put_task_struct(task); + pr_info("read: pid=%d opid=%d contid=%llu", pid_nr(task_tgid(current)), pid_nr(task_tgid(task)), audit_get_containerid(task)); return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); } @@ -1324,14 +1328,19 @@ static ssize_t proc_containerid_write(struct file *file, const char __user *buf, struct task_struct *task = get_proc_task(inode); if (!task) + { + pr_info("no inode owner"); return -ESRCH; + } if (*ppos != 0) { /* No partial writes. */ put_task_struct(task); + pr_info("no partial writes"); return -EINVAL; } rv = kstrtou64_from_user(buf, count, 10, &containerid); + pr_info("write: pid=%d rv=%d count=%ld opid=%d contid=%llu", task_tgid_nr(current), rv, count, task_tgid_nr(task), containerid); if (rv < 0) { put_task_struct(task); return rv; @@ -1339,6 +1348,7 @@ static ssize_t proc_containerid_write(struct file *file, const char __user *buf, rv = audit_set_containerid(task, containerid); put_task_struct(task); + //pr_info("audit_set_containerid: rv=%d", rv); if (rv < 0) return rv; return count; diff --git a/kernel/auditsc.c b/kernel/auditsc.c index fcee34e..39e7dc10 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -2111,16 +2111,28 @@ static int audit_set_containerid_perm(struct task_struct *task, u64 containerid) /* Don't allow to set our own containerid */ if (current == task) + { + pr_info("pid=%d can't set own containerid", task_tgid_nr(task)); return -EPERM; + } /* Don't allow the containerid to be unset */ if (!cid_valid(containerid)) + { + pr_info("can't unset containerid"); return -EINVAL; + } /* if we don't have caps, reject */ if (!capable(CAP_AUDIT_CONTROL)) + { + pr_info("don't have CAP_AUDIT_CONTROL"); return -EPERM; + } /* if containerid is unset, allow */ if (!audit_containerid_set(task)) + { + //pr_info("unset, allow"); return 0; + } /* it is already set, and not inherited from the parent, reject */ ccontainerid = audit_get_containerid(task); rcu_read_lock(); @@ -2131,7 +2143,11 @@ static int audit_set_containerid_perm(struct task_struct *task, u64 containerid) ppid = task_tgid_nr(parent); task_unlock(parent); if (ccontainerid != pcontainerid) + { + pr_info("pid=%d already has contid=%llu set, not inherited from ppid=%d with contid=%llu, can't set containerid %llu", + task_tgid_nr(task), ccontainerid, ppid, pcontainerid, containerid); return -EPERM; + } return 0; } -- 1.8.3.1