Re: [PATCH ghak59 V4] audit: add syscall information to CONFIG_CHANGE records

From: Paul Moore
Date: Fri Jan 18 2019 - 17:58:29 EST


On Fri, Jan 18, 2019 at 5:43 PM Richard Guy Briggs <rgb@xxxxxxxxxx> wrote:
> Tie syscall information to all CONFIG_CHANGE calls since they are all a
> result of user actions.
>
> Exclude user records from syscall context:
> Since the function audit_log_common_recv_msg() is shared by a number of
> AUDIT_CONFIG_CHANGE and the entire range of AUDIT_USER_* record types,
> and since the AUDIT_CONFIG_CHANGE message type has been converted to a
> syscall accompanied record type, special-case the AUDIT_USER_* range of
> messages so they remain standalone records.
>
> See: https://github.com/linux-audit/audit-kernel/issues/59
> See: https://github.com/linux-audit/audit-kernel/issues/50
> Signed-off-by: Richard Guy Briggs <rgb@xxxxxxxxxx>
> ---
> Changelog:
> v4:
> - rebase on v5.0-rc1
> - remove audit_log_config_change_alt() and call
> audit_log_common_recv_msg() directly
> - remove audit_tree_log_remove_rule() change superceded by patch v3-3/4
>
> Passes audit-testsuite, no issues identified with ausearch-test.
>
> kernel/audit.c | 27 ++++++++++++++++++---------
> kernel/audit_fsnotify.c | 2 +-
> kernel/audit_watch.c | 2 +-
> kernel/auditfilter.c | 2 +-
> 4 files changed, 21 insertions(+), 12 deletions(-)

Good timing, this hit my inbox just as I was making one last pass
before dinner. Looks good to me, merged into audit/next.

> diff --git a/kernel/audit.c b/kernel/audit.c
> index d412fb4ae6d5..ca55ccb46b76 100644
> --- a/kernel/audit.c
> +++ b/kernel/audit.c
> @@ -396,7 +396,7 @@ static int audit_log_config_change(char *function_name, u32 new, u32 old,
> struct audit_buffer *ab;
> int rc = 0;
>
> - ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
> + ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_CONFIG_CHANGE);
> if (unlikely(!ab))
> return rc;
> audit_log_format(ab, "op=set %s=%u old=%u ", function_name, new, old);
> @@ -1053,7 +1053,8 @@ static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type)
> return err;
> }
>
> -static void audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type)
> +static void audit_log_common_recv_msg(struct audit_context *context,
> + struct audit_buffer **ab, u16 msg_type)
> {
> uid_t uid = from_kuid(&init_user_ns, current_uid());
> pid_t pid = task_tgid_nr(current);
> @@ -1063,7 +1064,7 @@ static void audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type)
> return;
> }
>
> - *ab = audit_log_start(NULL, GFP_KERNEL, msg_type);
> + *ab = audit_log_start(context, GFP_KERNEL, msg_type);
> if (unlikely(!*ab))
> return;
> audit_log_format(*ab, "pid=%d uid=%u ", pid, uid);
> @@ -1071,6 +1072,11 @@ static void audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type)
> audit_log_task_context(*ab);
> }
>
> +static inline void audit_log_user_recv_msg(struct audit_buffer **ab, u16 msg_type)
> +{
> + audit_log_common_recv_msg(NULL, ab, msg_type);
> +}
> +
> int is_audit_feature_set(int i)
> {
> return af.features & AUDIT_FEATURE_TO_MASK(i);
> @@ -1338,7 +1344,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
> if (err)
> break;
> }
> - audit_log_common_recv_msg(&ab, msg_type);
> + audit_log_user_recv_msg(&ab, msg_type);
> if (msg_type != AUDIT_USER_TTY)
> audit_log_format(ab, " msg='%.*s'",
> AUDIT_MESSAGE_TEXT_MAX,
> @@ -1361,7 +1367,8 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
> if (nlmsg_len(nlh) < sizeof(struct audit_rule_data))
> return -EINVAL;
> if (audit_enabled == AUDIT_LOCKED) {
> - audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE);
> + audit_log_common_recv_msg(audit_context(), &ab,
> + AUDIT_CONFIG_CHANGE);
> audit_log_format(ab, " op=%s audit_enabled=%d res=0",
> msg_type == AUDIT_ADD_RULE ?
> "add_rule" : "remove_rule",
> @@ -1376,7 +1383,8 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
> break;
> case AUDIT_TRIM:
> audit_trim_trees();
> - audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE);
> + audit_log_common_recv_msg(audit_context(), &ab,
> + AUDIT_CONFIG_CHANGE);
> audit_log_format(ab, " op=trim res=1");
> audit_log_end(ab);
> break;
> @@ -1406,8 +1414,8 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
> /* OK, here comes... */
> err = audit_tag_tree(old, new);
>
> - audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE);
> -
> + audit_log_common_recv_msg(audit_context(), &ab,
> + AUDIT_CONFIG_CHANGE);
> audit_log_format(ab, " op=make_equiv old=");
> audit_log_untrustedstring(ab, old);
> audit_log_format(ab, " new=");
> @@ -1474,7 +1482,8 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
> old.enabled = t & AUDIT_TTY_ENABLE;
> old.log_passwd = !!(t & AUDIT_TTY_LOG_PASSWD);
>
> - audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE);
> + audit_log_common_recv_msg(audit_context(), &ab,
> + AUDIT_CONFIG_CHANGE);
> audit_log_format(ab, " op=tty_set old-enabled=%d new-enabled=%d"
> " old-log_passwd=%d new-log_passwd=%d res=%d",
> old.enabled, s.enabled, old.log_passwd,
> diff --git a/kernel/audit_fsnotify.c b/kernel/audit_fsnotify.c
> index cf4512a33675..37ae95cfb7f4 100644
> --- a/kernel/audit_fsnotify.c
> +++ b/kernel/audit_fsnotify.c
> @@ -127,7 +127,7 @@ static void audit_mark_log_rule_change(struct audit_fsnotify_mark *audit_mark, c
>
> if (!audit_enabled)
> return;
> - ab = audit_log_start(NULL, GFP_NOFS, AUDIT_CONFIG_CHANGE);
> + ab = audit_log_start(audit_context(), GFP_NOFS, AUDIT_CONFIG_CHANGE);
> if (unlikely(!ab))
> return;
> audit_log_session_info(ab);
> diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c
> index 20ef9ba134b0..e8d1adeb2223 100644
> --- a/kernel/audit_watch.c
> +++ b/kernel/audit_watch.c
> @@ -242,7 +242,7 @@ static void audit_watch_log_rule_change(struct audit_krule *r, struct audit_watc
>
> if (!audit_enabled)
> return;
> - ab = audit_log_start(NULL, GFP_NOFS, AUDIT_CONFIG_CHANGE);
> + ab = audit_log_start(audit_context(), GFP_NOFS, AUDIT_CONFIG_CHANGE);
> if (!ab)
> return;
> audit_log_session_info(ab);
> diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
> index bf309f2592c4..26a80a9d43a9 100644
> --- a/kernel/auditfilter.c
> +++ b/kernel/auditfilter.c
> @@ -1091,7 +1091,7 @@ static void audit_log_rule_change(char *action, struct audit_krule *rule, int re
> if (!audit_enabled)
> return;
>
> - ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
> + ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_CONFIG_CHANGE);
> if (!ab)
> return;
> audit_log_session_info(ab);
> --
> 1.8.3.1
>


--
paul moore
www.paul-moore.com