Re: [PATCH ghak90 (was ghak32) V4 09/10] audit: NETFILTER_PKT: record each container ID associated with a netNS
From: Paul Moore <paul@paul-moore.com>
Date: 2018-10-20 07:27:16
Also in:
linux-api, linux-fsdevel, lkml, netfilter-devel
On Sun, Aug 5, 2018 at 4:33 AM Richard Guy Briggs [off-list ref] wrote:
Add audit container identifier auxiliary record(s) to NETFILTER_PKT event standalone records. Iterate through all potential audit container identifiers associated with a network namespace. Signed-off-by: Richard Guy Briggs <redacted> --- include/linux/audit.h | 5 +++++ kernel/audit.c | 26 ++++++++++++++++++++++++++ net/netfilter/xt_AUDIT.c | 12 ++++++++++-- 3 files changed, 41 insertions(+), 2 deletions(-)
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quoted hunk ↗ jump to hunk
diff --git a/include/linux/audit.h b/include/linux/audit.h index 9a02095..8755f4d 100644 --- a/include/linux/audit.h +++ b/include/linux/audit.h@@ -169,6 +169,8 @@ extern int audit_log_contid(struct audit_context *context, extern void audit_netns_contid_add(struct net *net, u64 contid); extern void audit_netns_contid_del(struct net *net, u64 contid); extern void audit_switch_task_namespaces(struct nsproxy *ns, struct task_struct *p); +extern void audit_log_netns_contid_list(struct net *net, + struct audit_context *context); extern int audit_update_lsm_rules(void);@@ -228,6 +230,9 @@ static inline void audit_netns_contid_del(struct net *net, u64 contid) { } static inline void audit_switch_task_namespaces(struct nsproxy *ns, struct task_struct *p) { } +static inline void audit_log_netns_contid_list(struct net *net, + struct audit_context *context) +{ } #define audit_enabled AUDIT_OFF #endif /* CONFIG_AUDIT */diff --git a/kernel/audit.c b/kernel/audit.c index c5fed3b..b23711c 100644 --- a/kernel/audit.c +++ b/kernel/audit.c@@ -392,6 +392,32 @@ void audit_switch_task_namespaces(struct nsproxy *ns, struct task_struct *p) audit_netns_contid_add(new->net_ns, contid); } +void audit_log_netns_contid_list(struct net *net, struct audit_context *context) +{ + spinlock_t *lock = audit_get_netns_contid_list_lock(net); + struct audit_buffer *ab; + struct audit_contid *cont; + bool first = true; + + /* Generate AUDIT_CONTAINER record with container ID CSV list */ + ab = audit_log_start(context, GFP_ATOMIC, AUDIT_CONTAINER); + if (!ab) { + audit_log_lost("out of memory in audit_log_netns_contid_list"); + return; + } + audit_log_format(ab, "contid="); + spin_lock(lock); + list_for_each_entry(cont, audit_get_netns_contid_list(net), list) { + if (!first) + audit_log_format(ab, ","); + audit_log_format(ab, "%llu", cont->id); + first = false; + } + spin_unlock(lock);
This is looking like potentially a lot of work to be doing under a spinlock, not to mention a single spinlock that is shared across CPUs. Considering that I expect changes to the list to be somewhat infrequent, this might be a good candidate for a RCU based locking scheme.
quoted hunk ↗ jump to hunk
+ audit_log_end(ab); +} +EXPORT_SYMBOL(audit_log_netns_contid_list); void audit_panic(const char *message) { switch (audit_failure) {diff --git a/net/netfilter/xt_AUDIT.c b/net/netfilter/xt_AUDIT.c index af883f1..44fac3f 100644 --- a/net/netfilter/xt_AUDIT.c +++ b/net/netfilter/xt_AUDIT.c@@ -71,10 +71,13 @@ static bool audit_ip6(struct audit_buffer *ab, struct sk_buff *skb) { struct audit_buffer *ab; int fam = -1; + struct audit_context *context; + struct net *net; if (audit_enabled == AUDIT_OFF) - goto errout; - ab = audit_log_start(NULL, GFP_ATOMIC, AUDIT_NETFILTER_PKT); + goto out; + context = audit_alloc_local(GFP_ATOMIC); + ab = audit_log_start(context, GFP_ATOMIC, AUDIT_NETFILTER_PKT); if (ab == NULL) goto errout;@@ -104,7 +107,12 @@ static bool audit_ip6(struct audit_buffer *ab, struct sk_buff *skb) audit_log_end(ab); + net = xt_net(par); + audit_log_netns_contid_list(net, context); + errout: + audit_free_context(context); +out: return XT_CONTINUE; }
-- paul moore www.paul-moore.com