[PATCH ghak59 V3 3/4] audit: hand taken context to audit_kill_trees for syscall logging
Paul Moore
paul at paul-moore.com
Mon Jan 14 23:06:15 UTC 2019
On Mon, Dec 10, 2018 at 5:18 PM Richard Guy Briggs <rgb at redhat.com> wrote:
>
> Since the context is derived from the task parameter handed to
> __audit_free(), hand the context to audit_kill_trees() so it can be used
> to associate with a syscall record. This requires adding the context
> parameter to kill_rules() rather than using the current audit_context.
>
> The callers of trim_marked() and evict_chunk() still have their context.
>
> The EOE record was being issued prior to the pruning of the killed_tree
> list.
>
> Move the kill_trees call before the audit_log_exit call in
> __audit_free() and __audit_syscall_exit() so that any pruned trees
> CONFIG_CHANGE records are included with the associated syscall event by
> the user library due to the EOE record flagging the end of the event.
>
> See: https://github.com/linux-audit/audit-kernel/issues/50
> See: https://github.com/linux-audit/audit-kernel/issues/59
> Signed-off-by: Richard Guy Briggs <rgb at redhat.com>
> ---
> kernel/audit.h | 4 ++--
> kernel/audit_tree.c | 18 ++++++++++--------
> kernel/auditsc.c | 12 ++++++------
> 3 files changed, 18 insertions(+), 16 deletions(-)
Merged.
> diff --git a/kernel/audit.h b/kernel/audit.h
> index 91421679a168..6ffb70575082 100644
> --- a/kernel/audit.h
> +++ b/kernel/audit.h
> @@ -314,7 +314,7 @@ extern void audit_log_d_path_exe(struct audit_buffer *ab,
> extern int audit_tag_tree(char *old, char *new);
> extern const char *audit_tree_path(struct audit_tree *tree);
> extern void audit_put_tree(struct audit_tree *tree);
> -extern void audit_kill_trees(struct list_head *list);
> +extern void audit_kill_trees(struct audit_context *context);
> #else
> #define audit_remove_tree_rule(rule) BUG()
> #define audit_add_tree_rule(rule) -EINVAL
> @@ -323,7 +323,7 @@ extern void audit_log_d_path_exe(struct audit_buffer *ab,
> #define audit_put_tree(tree) (void)0
> #define audit_tag_tree(old, new) -EINVAL
> #define audit_tree_path(rule) "" /* never called */
> -#define audit_kill_trees(list) BUG()
> +#define audit_kill_trees(context) BUG()
> #endif
>
> extern char *audit_unpack_string(void **bufp, size_t *remain, size_t len);
> diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c
> index b0bd59ef4271..bf77d265e68e 100644
> --- a/kernel/audit_tree.c
> +++ b/kernel/audit_tree.c
> @@ -524,13 +524,13 @@ static int tag_chunk(struct inode *inode, struct audit_tree *tree)
> return 0;
> }
>
> -static void audit_tree_log_remove_rule(struct audit_krule *rule)
> +static void audit_tree_log_remove_rule(struct audit_context *context, struct audit_krule *rule)
> {
> struct audit_buffer *ab;
>
> if (!audit_enabled)
> return;
> - ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_CONFIG_CHANGE);
> + ab = audit_log_start(context, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
> if (unlikely(!ab))
> return;
> audit_log_format(ab, "op=remove_rule dir=");
> @@ -540,7 +540,7 @@ static void audit_tree_log_remove_rule(struct audit_krule *rule)
> audit_log_end(ab);
> }
>
> -static void kill_rules(struct audit_tree *tree)
> +static void kill_rules(struct audit_context *context, struct audit_tree *tree)
> {
> struct audit_krule *rule, *next;
> struct audit_entry *entry;
> @@ -551,7 +551,7 @@ static void kill_rules(struct audit_tree *tree)
> list_del_init(&rule->rlist);
> if (rule->tree) {
> /* not a half-baked one */
> - audit_tree_log_remove_rule(rule);
> + audit_tree_log_remove_rule(context, rule);
> if (entry->rule.exe)
> audit_remove_mark(entry->rule.exe);
> rule->tree = NULL;
> @@ -633,7 +633,7 @@ static void trim_marked(struct audit_tree *tree)
> tree->goner = 1;
> spin_unlock(&hash_lock);
> mutex_lock(&audit_filter_mutex);
> - kill_rules(tree);
> + kill_rules(audit_context(), tree);
> list_del_init(&tree->list);
> mutex_unlock(&audit_filter_mutex);
> prune_one(tree);
> @@ -973,8 +973,10 @@ static void audit_schedule_prune(void)
> * ... and that one is done if evict_chunk() decides to delay until the end
> * of syscall. Runs synchronously.
> */
> -void audit_kill_trees(struct list_head *list)
> +void audit_kill_trees(struct audit_context *context)
> {
> + struct list_head *list = &context->killed_trees;
> +
> audit_ctl_lock();
> mutex_lock(&audit_filter_mutex);
>
> @@ -982,7 +984,7 @@ void audit_kill_trees(struct list_head *list)
> struct audit_tree *victim;
>
> victim = list_entry(list->next, struct audit_tree, list);
> - kill_rules(victim);
> + kill_rules(context, victim);
> list_del_init(&victim->list);
>
> mutex_unlock(&audit_filter_mutex);
> @@ -1017,7 +1019,7 @@ static void evict_chunk(struct audit_chunk *chunk)
> list_del_init(&owner->same_root);
> spin_unlock(&hash_lock);
> if (!postponed) {
> - kill_rules(owner);
> + kill_rules(audit_context(), owner);
> list_move(&owner->list, &prune_list);
> need_prune = 1;
> } else {
> diff --git a/kernel/auditsc.c b/kernel/auditsc.c
> index 6593a5207fb0..b585ceb2f7a2 100644
> --- a/kernel/auditsc.c
> +++ b/kernel/auditsc.c
> @@ -1444,6 +1444,9 @@ void __audit_free(struct task_struct *tsk)
> if (!context)
> return;
>
> + if (!list_empty(&context->killed_trees))
> + audit_kill_trees(context);
> +
> /* We are called either by do_exit() or the fork() error handling code;
> * in the former case tsk == current and in the latter tsk is a
> * random task_struct that doesn't doesn't have any meaningful data we
> @@ -1460,9 +1463,6 @@ void __audit_free(struct task_struct *tsk)
> audit_log_exit();
> }
>
> - if (!list_empty(&context->killed_trees))
> - audit_kill_trees(&context->killed_trees);
> -
> audit_set_context(tsk, NULL);
> audit_free_context(context);
> }
> @@ -1537,6 +1537,9 @@ void __audit_syscall_exit(int success, long return_code)
> if (!context)
> return;
>
> + if (!list_empty(&context->killed_trees))
> + audit_kill_trees(context);
> +
> if (!context->dummy && context->in_syscall) {
> if (success)
> context->return_valid = AUDITSC_SUCCESS;
> @@ -1571,9 +1574,6 @@ void __audit_syscall_exit(int success, long return_code)
> context->in_syscall = 0;
> context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
>
> - if (!list_empty(&context->killed_trees))
> - audit_kill_trees(&context->killed_trees);
> -
> audit_free_names(context);
> unroll_tree_refs(context, NULL, 0);
> audit_free_aux(context);
> --
> 1.8.3.1
>
--
paul moore
www.paul-moore.com
More information about the Linux-audit
mailing list