Re: [PATCH ghak124 v3] audit: log nftables configuration change events

On Wed, Jun 24, 2020 at 08:34:23AM -0400, Richard Guy Briggs wrote: > On 2020-06-24 12:03, Pablo Neira Ayuso wrote: > > On Thu, Jun 04, 2020 at 09:20:49AM -0400, Richard Guy Briggs wrote: [...] > > > diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c > > > index 3558e76e2733..b9e7440cc87d 100644 > > > --- a/net/netfilter/nf_tables_api.c > > > +++ b/net/netfilter/nf_tables_api.c > > > @@ -12,6 +12,7 @@ > > > #include <linux/netlink.h> > > > #include <linux/vmalloc.h> > > > #include <linux/rhashtable.h> > > > +#include <linux/audit.h> > > > #include <linux/netfilter.h> > > > #include <linux/netfilter/nfnetlink.h> > > > #include <linux/netfilter/nf_tables.h> > > > @@ -693,6 +694,16 @@ static void nf_tables_table_notify(const struct nft_ctx *ctx, int event) > > > { > > > struct sk_buff *skb; > > > int err; > > > + char *buf = kasprintf(GFP_KERNEL, "%s:%llu;?:0", > > > + ctx->table->name, ctx->table->handle); > > > + > > > + audit_log_nfcfg(buf, > > > + ctx->family, > > > + ctx->table->use, > > > + event == NFT_MSG_NEWTABLE ? > > > + AUDIT_NFT_OP_TABLE_REGISTER : > > > + AUDIT_NFT_OP_TABLE_UNREGISTER); > > > + kfree(buf); > > > > As a follow up: Would you wrap this code into a function? > > > > nft_table_audit() > > > > Same thing for other pieces of code below. > > If I'm guessing right, you are asking for a supplementary follow-up > cleanup patch to this one (or are you nacking this patch)? No nack, it's just that I'd prefer to see this wrapped in a function. I think your patch is already in the audit tree. > Also, I gather you would like to see the kasprintf and kfree hidden in > nft_table_audit(), handing this function at least 8 parameters? This > sounds pretty messy given the format of the table field. I think you can pass ctx and the specific object, e.g. table, in most cases? There is also event and the gfp_flags. That counts 4 here, but maybe I'm overlooking something.

Thanks.