4.14-stable review patch. If anyone has any objections, please let me know.
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From: Steve Grubb sgrubb@redhat.com
[ Upstream commit 33e8a907804428109ce1d12301c3365d619cc4df ]
The API to end auditing has historically been for auditd to set the pid to 0. This patch restores that functionality.
See: https://github.com/linux-audit/audit-kernel/issues/69
Reviewed-by: Richard Guy Briggs rgb@redhat.com Signed-off-by: Steve Grubb sgrubb@redhat.com Signed-off-by: Paul Moore paul@paul-moore.com Signed-off-by: Sasha Levin alexander.levin@verizon.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- kernel/audit.c | 29 ++++++++++++++++------------- 1 file changed, 16 insertions(+), 13 deletions(-)
--- a/kernel/audit.c +++ b/kernel/audit.c @@ -1197,25 +1197,28 @@ static int audit_receive_msg(struct sk_b pid_t auditd_pid; struct pid *req_pid = task_tgid(current);
- /* sanity check - PID values must match */ - if (new_pid != pid_vnr(req_pid)) + /* Sanity check - PID values must match. Setting + * pid to 0 is how auditd ends auditing. */ + if (new_pid && (new_pid != pid_vnr(req_pid))) return -EINVAL;
/* test the auditd connection */ audit_replace(req_pid);
auditd_pid = auditd_pid_vnr(); - /* only the current auditd can unregister itself */ - if ((!new_pid) && (new_pid != auditd_pid)) { - audit_log_config_change("audit_pid", new_pid, - auditd_pid, 0); - return -EACCES; - } - /* replacing a healthy auditd is not allowed */ - if (auditd_pid && new_pid) { - audit_log_config_change("audit_pid", new_pid, - auditd_pid, 0); - return -EEXIST; + if (auditd_pid) { + /* replacing a healthy auditd is not allowed */ + if (new_pid) { + audit_log_config_change("audit_pid", + new_pid, auditd_pid, 0); + return -EEXIST; + } + /* only current auditd can unregister itself */ + if (pid_vnr(req_pid) != auditd_pid) { + audit_log_config_change("audit_pid", + new_pid, auditd_pid, 0); + return -EACCES; + } }
if (new_pid) {