Re: [PATCH v4 3/4] fanotify, audit: Allow audit to use the full permission event response

> > diff --git a/kernel/auditsc.c b/kernel/auditsc.c > > index 433418d73584..f000fec52360 100644 > > --- a/kernel/auditsc.c > > +++ b/kernel/auditsc.c > > @@ -64,6 +64,7 @@ > > #include <uapi/linux/limits.h> > > #include <uapi/linux/netfilter/nf_tables.h> > > #include <uapi/linux/openat2.h> // struct open_how > > +#include <uapi/linux/fanotify.h> > > > > #include "audit.h" > > > > @@ -2899,10 +2900,34 @@ void __audit_log_kern_module(char *name) > > context->type = AUDIT_KERN_MODULE; > > } > > > > -void __audit_fanotify(u32 response) > > +void __audit_fanotify(u32 response, size_t len, char *buf) > > { > > - audit_log(audit_context(), GFP_KERNEL, > > - AUDIT_FANOTIFY, "resp=%u", response); > > + struct fanotify_response_info_audit_rule *friar; > > + size_t c = len; > > + char *ib = buf; > > + > > + if (!(len && buf)) { > > + audit_log(audit_context(), GFP_KERNEL, AUDIT_FANOTIFY, > > + "resp=%u fan_type=0 fan_info=?", response); > > + return; > > + } > > + while (c >= sizeof(struct fanotify_response_info_header)) { > > + friar = (struct fanotify_response_info_audit_rule > > *)buf; > > Since the only use of this at the moment is the > fanotify_response_info_rule, why not pass the > fanotify_response_info_rule struct directly into this function? We > can always change it if we need to in the future without affecting > userspace, and it would simplify the code. Steve, would it make any sense for there to be more than one FAN_RESPONSE_INFO_AUDIT_RULE header in a message? Could there be more than one rule that contributes to a notify reason? If not, would it be reasonable to return -EINVAL if there is more than one?