[PATCH v3 1/4] selinux: inline some AVC functions used only once

[Stephen Smalley]

On 1/25/19 5:06 AM, Ondrej Mosnacek wrote:
> avc_dump_av() and avc_dump_query() are each used only in one place. Get
> rid of them and open code their contents in the call sites.
> 
> Signed-off-by: Ondrej Mosnacek <omosnace at redhat.com>

Reviewed-by: Stephen Smalley <sds at tycho.nsa.gov>

> ---
>   security/selinux/avc.c | 140 +++++++++++++++++------------------------
>   1 file changed, 58 insertions(+), 82 deletions(-)
> 
> diff --git a/security/selinux/avc.c b/security/selinux/avc.c
> index 9b63d8ee1687..502162eeb3a0 100644
> --- a/security/selinux/avc.c
> +++ b/security/selinux/avc.c
> @@ -129,75 +129,6 @@ static inline int avc_hash(u32 ssid, u32 tsid, u16 tclass)
>   	return (ssid ^ (tsid<<2) ^ (tclass<<4)) & (AVC_CACHE_SLOTS - 1);
>   }
>   
> -/**
> - * avc_dump_av - Display an access vector in human-readable form.
> - * @tclass: target security class
> - * @av: access vector
> - */
> -static void avc_dump_av(struct audit_buffer *ab, u16 tclass, u32 av)
> -{
> -	const char **perms;
> -	int i, perm;
> -
> -	if (av == 0) {
> -		audit_log_format(ab, " null");
> -		return;
> -	}
> -
> -	BUG_ON(!tclass || tclass >= ARRAY_SIZE(secclass_map));
> -	perms = secclass_map[tclass-1].perms;
> -
> -	audit_log_format(ab, " {");
> -	i = 0;
> -	perm = 1;
> -	while (i < (sizeof(av) * 8)) {
> -		if ((perm & av) && perms[i]) {
> -			audit_log_format(ab, " %s", perms[i]);
> -			av &= ~perm;
> -		}
> -		i++;
> -		perm <<= 1;
> -	}
> -
> -	if (av)
> -		audit_log_format(ab, " 0x%x", av);
> -
> -	audit_log_format(ab, " }");
> -}
> -
> -/**
> - * avc_dump_query - Display a SID pair and a class in human-readable form.
> - * @ssid: source security identifier
> - * @tsid: target security identifier
> - * @tclass: target security class
> - */
> -static void avc_dump_query(struct audit_buffer *ab, struct selinux_state *state,
> -			   u32 ssid, u32 tsid, u16 tclass)
> -{
> -	int rc;
> -	char *scontext;
> -	u32 scontext_len;
> -
> -	rc = security_sid_to_context(state, ssid, &scontext, &scontext_len);
> -	if (rc)
> -		audit_log_format(ab, "ssid=%d", ssid);
> -	else {
> -		audit_log_format(ab, "scontext=%s", scontext);
> -		kfree(scontext);
> -	}
> -
> -	rc = security_sid_to_context(state, tsid, &scontext, &scontext_len);
> -	if (rc)
> -		audit_log_format(ab, " tsid=%d", tsid);
> -	else {
> -		audit_log_format(ab, " tcontext=%s", scontext);
> -		kfree(scontext);
> -	}
> -
> -	BUG_ON(!tclass || tclass >= ARRAY_SIZE(secclass_map));
> -	audit_log_format(ab, " tclass=%s", secclass_map[tclass-1].name);
> -}
> -
>   /**
>    * avc_init - Initialize the AVC.
>    *
> @@ -735,11 +666,37 @@ out:
>   static void avc_audit_pre_callback(struct audit_buffer *ab, void *a)
>   {
>   	struct common_audit_data *ad = a;
> -	audit_log_format(ab, "avc:  %s ",
> -			 ad->selinux_audit_data->denied ? "denied" : "granted");
> -	avc_dump_av(ab, ad->selinux_audit_data->tclass,
> -			ad->selinux_audit_data->audited);
> -	audit_log_format(ab, " for ");
> +	struct selinux_audit_data *sad = ad->selinux_audit_data;
> +	u32 av = sad->audited;
> +	const char **perms;
> +	int i, perm;
> +
> +	audit_log_format(ab, "avc:  %s ", sad->denied ? "denied" : "granted");
> +
> +	if (av == 0) {
> +		audit_log_string(ab, " null");
> +		return;
> +	}
> +
> +	BUG_ON(!sad->tclass || sad->tclass >= ARRAY_SIZE(secclass_map));
> +	perms = secclass_map[sad->tclass-1].perms;
> +
> +	audit_log_string(ab, " {");
> +	i = 0;
> +	perm = 1;
> +	while (i < (sizeof(av) * 8)) {
> +		if ((perm & av) && perms[i]) {
> +			audit_log_format(ab, " %s", perms[i]);
> +			av &= ~perm;
> +		}
> +		i++;
> +		perm <<= 1;
> +	}
> +
> +	if (av)
> +		audit_log_format(ab, " 0x%x", av);
> +
> +	audit_log_string(ab, " } for ");
>   }
>   
>   /**
> @@ -751,15 +708,34 @@ static void avc_audit_pre_callback(struct audit_buffer *ab, void *a)
>   static void avc_audit_post_callback(struct audit_buffer *ab, void *a)
>   {
>   	struct common_audit_data *ad = a;
> -	audit_log_format(ab, " ");
> -	avc_dump_query(ab, ad->selinux_audit_data->state,
> -		       ad->selinux_audit_data->ssid,
> -		       ad->selinux_audit_data->tsid,
> -		       ad->selinux_audit_data->tclass);
> -	if (ad->selinux_audit_data->denied) {
> -		audit_log_format(ab, " permissive=%u",
> -				 ad->selinux_audit_data->result ? 0 : 1);
> +	struct selinux_audit_data *sad = ad->selinux_audit_data;
> +	char *scontext;
> +	u32 scontext_len;
> +	int rc;
> +
> +	rc = security_sid_to_context(sad->state, sad->ssid, &scontext,
> +				     &scontext_len);
> +	if (rc)
> +		audit_log_format(ab, " ssid=%d", sad->ssid);
> +	else {
> +		audit_log_format(ab, " scontext=%s", scontext);
> +		kfree(scontext);
>   	}
> +
> +	rc = security_sid_to_context(sad->state, sad->tsid, &scontext,
> +				     &scontext_len);
> +	if (rc)
> +		audit_log_format(ab, " tsid=%d", sad->tsid);
> +	else {
> +		audit_log_format(ab, " tcontext=%s", scontext);
> +		kfree(scontext);
> +	}
> +
> +	BUG_ON(!sad->tclass || sad->tclass >= ARRAY_SIZE(secclass_map));
> +	audit_log_format(ab, " tclass=%s", secclass_map[sad->tclass-1].name);
> +
> +	if (sad->denied)
> +		audit_log_format(ab, " permissive=%u", sad->result ? 0 : 1);
>   }
>   
>   /* This is the slow part of avc audit with big stack footprint */
>