Re: [PATCH v5 3/3] fanotify,audit: Allow audit to use the full permission event response

On 2022-12-20 18:31, Paul Moore wrote: > On Mon, Dec 12, 2022 at 9:06 AM Richard Guy Briggs <rgb(a)redhat.com&gt; wrote: > > > > This patch passes the full response so that the audit function can use all > > of it. The audit function was updated to log the additional information in > > the AUDIT_FANOTIFY record. > > > > Currently the only type of fanotify info that is defined is an audit > > rule number, but convert it to hex encoding to future-proof the field. > > Hex encoding suggested by Paul Moore <paul(a)paul-moore.com&gt;. > > > > Sample records: > > type=FANOTIFY msg=audit(1600385147.372:590): resp=2 fan_type=1 fan_info=3137 subj_trust=3 obj_trust=5 > > type=FANOTIFY msg=audit(1659730979.839:284): resp=1 fan_type=0 fan_info=3F subj_trust=2 obj_trust=2 > > > > Suggested-by: Steve Grubb <sgrubb(a)redhat.com&gt; > > Link: https://lore.kernel.org/r/3075502.aeNJFYEL58@x2 > > Signed-off-by: Richard Guy Briggs <rgb(a)redhat.com&gt; > > --- > > fs/notify/fanotify/fanotify.c | 3 ++- > > include/linux/audit.h | 9 +++++---- > > kernel/auditsc.c | 25 ++++++++++++++++++++++--- > > 3 files changed, 29 insertions(+), 8 deletions(-) > > ... > > > diff --git a/kernel/auditsc.c b/kernel/auditsc.c > > index d1fb821de104..8d523066d81f 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" > > > > @@ -2877,10 +2878,28 @@ void __audit_log_kern_module(char *name) > > context->type = AUDIT_KERN_MODULE; > > } > > > > -void __audit_fanotify(u32 response) > > +void __audit_fanotify(u32 response, struct fanotify_response_info_audit_rule *friar) > > { > > - audit_log(audit_context(), GFP_KERNEL, > > - AUDIT_FANOTIFY, "resp=%u", response); > > + struct audit_context *ctx = audit_context(); > > + struct audit_buffer *ab; > > + char numbuf[12]; > > + > > + if (friar->hdr.type == FAN_RESPONSE_INFO_NONE) { > > + audit_log(audit_context(), GFP_KERNEL, AUDIT_FANOTIFY, > > + "resp=%u fan_type=%u fan_info=3F subj_trust=2 obj_trust=2", > > + response, FAN_RESPONSE_INFO_NONE); > > The fan_info, subj_trust, and obj_trust constant values used here are > awfully magic-numbery and not the usual sentinel values one might > expect for a "none" operation, e.g. zeros/INT_MAX/etc. I believe a > comment here explaining the values would be a good idea. Ack. I'll add a comment. I would have preferred zero for default of unset, but Steve requested 0/1/2 no/yes/unknown.