Re: [PATCH 3/9] Audit: use new LSM hooks instead of SELinux exports

[Paul Moore <paul.moore@hp.com>]

On Saturday 01 March 2008 2:54:38 pm Ahmed S. Darwish wrote:
> Stop using the following exported SELinux interfaces:
> selinux_get_inode_sid(inode, sid)
> selinux_get_ipc_sid(ipcp, sid)
> selinux_get_task_sid(tsk, sid)
> selinux_sid_to_string(sid, ctx, len)
> kfree(ctx)
>
> and use following generic LSM equivalents respectively:
> security_inode_getsecid(inode, secid)
> security_ipc_getsecid*(ipcp, secid)
> security_task_getsecid(tsk, secid)
> security_sid_to_secctx(sid, ctx, len)
> security_release_secctx(ctx, len)
>
> Call security_release_secctx only if security_secid_to_secctx
> succeeded.

Thanks for fixing this while you were making your changes.

> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
> Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>

Reviewed-by: Paul Moore <paul.moore@hp.com>

> ---
>
>  audit.c       |   17 +++++++++--------
>  auditfilter.c |    8 +++++---
>  auditsc.c     |   55
> +++++++++++++++++++++++++++++-------------------------- 3 files
> changed, 43 insertions(+), 37 deletions(-)
>
> diff --git a/kernel/audit.c b/kernel/audit.c
> index 8316a88..d79f866 100644
> --- a/kernel/audit.c
> +++ b/kernel/audit.c
> @@ -259,13 +259,13 @@ static int audit_log_config_change(char
> *function_name, int new, int old, char *ctx = NULL;
>  		u32 len;
>
> -		rc = selinux_sid_to_string(sid, &ctx, &len);
> +		rc = security_secid_to_secctx(sid, &ctx, &len);
>  		if (rc) {
>  			audit_log_format(ab, " sid=%u", sid);
>  			allow_changes = 0; /* Something weird, deny request */
>  		} else {
>  			audit_log_format(ab, " subj=%s", ctx);
> -			kfree(ctx);
> +			security_release_secctx(ctx, len);
>  		}
>  	}
>  	audit_log_format(ab, " res=%d", allow_changes);
> @@ -543,12 +543,13 @@ static int audit_log_common_recv_msg(struct
> audit_buffer **ab, u16 msg_type, audit_log_format(*ab, "user pid=%d
> uid=%u auid=%u",
>  			 pid, uid, auid);
>  	if (sid) {
> -		rc = selinux_sid_to_string(sid, &ctx, &len);
> +		rc = security_secid_to_secctx(sid, &ctx, &len);
>  		if (rc)
>  			audit_log_format(*ab, " ssid=%u", sid);
> -		else
> +		else {
>  			audit_log_format(*ab, " subj=%s", ctx);
> -		kfree(ctx);
> +			security_release_secctx(ctx, len);
> +		}
>  	}
>
>  	return rc;
> @@ -750,18 +751,18 @@ static int audit_receive_msg(struct sk_buff
> *skb, struct nlmsghdr *nlh) break;
>  	}
>  	case AUDIT_SIGNAL_INFO:
> -		err = selinux_sid_to_string(audit_sig_sid, &ctx, &len);
> +		err = security_secid_to_secctx(audit_sig_sid, &ctx, &len);
>  		if (err)
>  			return err;
>  		sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL);
>  		if (!sig_data) {
> -			kfree(ctx);
> +			security_release_secctx(ctx, len);
>  			return -ENOMEM;
>  		}
>  		sig_data->uid = audit_sig_uid;
>  		sig_data->pid = audit_sig_pid;
>  		memcpy(sig_data->ctx, ctx, len);
> -		kfree(ctx);
> +		security_release_secctx(ctx, len);
>  		audit_send_reply(NETLINK_CB(skb).pid, seq, AUDIT_SIGNAL_INFO,
>  				0, 0, sig_data, sizeof(*sig_data) + len);
>  		kfree(sig_data);
> diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
> index 2f2914b..35e58a1 100644
> --- a/kernel/auditfilter.c
> +++ b/kernel/auditfilter.c
> @@ -28,6 +28,7 @@
>  #include <linux/netlink.h>
>  #include <linux/sched.h>
>  #include <linux/inotify.h>
> +#include <linux/security.h>
>  #include <linux/selinux.h>
>  #include "audit.h"
>
> @@ -1515,11 +1516,12 @@ static void audit_log_rule_change(uid_t
> loginuid, u32 sid, char *action, if (sid) {
>  		char *ctx = NULL;
>  		u32 len;
> -		if (selinux_sid_to_string(sid, &ctx, &len))
> +		if (security_secid_to_secctx(sid, &ctx, &len))
>  			audit_log_format(ab, " ssid=%u", sid);
> -		else
> +		else {
>  			audit_log_format(ab, " subj=%s", ctx);
> -		kfree(ctx);
> +			security_release_secctx(ctx, len);
> +		}
>  	}
>  	audit_log_format(ab, " op=%s rule key=", action);
>  	if (rule->filterkey)
> diff --git a/kernel/auditsc.c b/kernel/auditsc.c
> index d07fc4a..a9fc9dd 100644
> --- a/kernel/auditsc.c
> +++ b/kernel/auditsc.c
> @@ -530,7 +530,7 @@ static int audit_filter_rules(struct task_struct
> *tsk, logged upon error */
>  			if (f->se_rule) {
>  				if (need_sid) {
> -					selinux_get_task_sid(tsk, &sid);
> +					security_task_getsecid(tsk, &sid);
>  					need_sid = 0;
>  				}
>  				result = selinux_audit_rule_match(sid, f->type,
> @@ -885,11 +885,11 @@ void audit_log_task_context(struct audit_buffer
> *ab) int error;
>  	u32 sid;
>
> -	selinux_get_task_sid(current, &sid);
> +	security_task_getsecid(current, &sid);
>  	if (!sid)
>  		return;
>
> -	error = selinux_sid_to_string(sid, &ctx, &len);
> +	error = security_secid_to_secctx(sid, &ctx, &len);
>  	if (error) {
>  		if (error != -EINVAL)
>  			goto error_path;
> @@ -897,7 +897,7 @@ void audit_log_task_context(struct audit_buffer
> *ab) }
>
>  	audit_log_format(ab, " subj=%s", ctx);
> -	kfree(ctx);
> +	security_release_secctx(ctx, len);
>  	return;
>
>  error_path:
> @@ -941,7 +941,7 @@ static int audit_log_pid_context(struct
> audit_context *context, pid_t pid, u32 sid, char *comm)
>  {
>  	struct audit_buffer *ab;
> -	char *s = NULL;
> +	char *ctx = NULL;
>  	u32 len;
>  	int rc = 0;
>
> @@ -951,15 +951,16 @@ static int audit_log_pid_context(struct
> audit_context *context, pid_t pid,
>
>  	audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, auid,
>  			 uid, sessionid);
> -	if (selinux_sid_to_string(sid, &s, &len)) {
> +	if (security_secid_to_secctx(sid, &ctx, &len)) {
>  		audit_log_format(ab, " obj=(none)");
>  		rc = 1;
> -	} else
> -		audit_log_format(ab, " obj=%s", s);
> +	} else {
> +		audit_log_format(ab, " obj=%s", ctx);
> +		security_release_secctx(ctx, len);
> +	}
>  	audit_log_format(ab, " ocomm=");
>  	audit_log_untrustedstring(ab, comm);
>  	audit_log_end(ab);
> -	kfree(s);
>
>  	return rc;
>  }
> @@ -1268,14 +1269,15 @@ static void audit_log_exit(struct
> audit_context *context, struct task_struct *ts if (axi->osid != 0) {
>  				char *ctx = NULL;
>  				u32 len;
> -				if (selinux_sid_to_string(
> +				if (security_secid_to_secctx(
>  						axi->osid, &ctx, &len)) {
>  					audit_log_format(ab, " osid=%u",
>  							axi->osid);
>  					call_panic = 1;
> -				} else
> +				} else {
>  					audit_log_format(ab, " obj=%s", ctx);
> -				kfree(ctx);
> +					security_release_secctx(ctx, len);
> +				}
>  			}
>  			break; }
>
> @@ -1389,13 +1391,14 @@ static void audit_log_exit(struct
> audit_context *context, struct task_struct *ts if (n->osid != 0) {
>  			char *ctx = NULL;
>  			u32 len;
> -			if (selinux_sid_to_string(
> +			if (security_secid_to_secctx(
>  				n->osid, &ctx, &len)) {
>  				audit_log_format(ab, " osid=%u", n->osid);
>  				call_panic = 2;
> -			} else
> +			} else {
>  				audit_log_format(ab, " obj=%s", ctx);
> -			kfree(ctx);
> +				security_release_secctx(ctx, len);
> +			}
>  		}
>
>  		audit_log_end(ab);
> @@ -1772,7 +1775,7 @@ static void audit_copy_inode(struct audit_names
> *name, const struct inode *inode name->uid   = inode->i_uid;
>  	name->gid   = inode->i_gid;
>  	name->rdev  = inode->i_rdev;
> -	selinux_get_inode_sid(inode, &name->osid);
> +	security_inode_getsecid(inode, &name->osid);
>  }
>
>  /**
> @@ -2187,8 +2190,7 @@ int __audit_ipc_obj(struct kern_ipc_perm *ipcp)
>  	ax->uid = ipcp->uid;
>  	ax->gid = ipcp->gid;
>  	ax->mode = ipcp->mode;
> -	selinux_get_ipc_sid(ipcp, &ax->osid);
> -
> +	security_ipc_getsecid(ipcp, &ax->osid);
>  	ax->d.type = AUDIT_IPC;
>  	ax->d.next = context->aux;
>  	context->aux = (void *)ax;
> @@ -2340,7 +2342,7 @@ void __audit_ptrace(struct task_struct *t)
>  	context->target_auid = audit_get_loginuid(t);
>  	context->target_uid = t->uid;
>  	context->target_sessionid = audit_get_sessionid(t);
> -	selinux_get_task_sid(t, &context->target_sid);
> +	security_task_getsecid(t, &context->target_sid);
>  	memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
>  }
>
> @@ -2368,7 +2370,7 @@ int __audit_signal_info(int sig, struct
> task_struct *t) audit_sig_uid = tsk->loginuid;
>  			else
>  				audit_sig_uid = tsk->uid;
> -			selinux_get_task_sid(tsk, &audit_sig_sid);
> +			security_task_getsecid(tsk, &audit_sig_sid);
>  		}
>  		if (!audit_signals || audit_dummy_context())
>  			return 0;
> @@ -2381,7 +2383,7 @@ int __audit_signal_info(int sig, struct
> task_struct *t) ctx->target_auid = audit_get_loginuid(t);
>  		ctx->target_uid = t->uid;
>  		ctx->target_sessionid = audit_get_sessionid(t);
> -		selinux_get_task_sid(t, &ctx->target_sid);
> +		security_task_getsecid(t, &ctx->target_sid);
>  		memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
>  		return 0;
>  	}
> @@ -2402,7 +2404,7 @@ int __audit_signal_info(int sig, struct
> task_struct *t) axp->target_auid[axp->pid_count] =
> audit_get_loginuid(t);
>  	axp->target_uid[axp->pid_count] = t->uid;
>  	axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
> -	selinux_get_task_sid(t, &axp->target_sid[axp->pid_count]);
> +	security_task_getsecid(t, &axp->target_sid[axp->pid_count]);
>  	memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
>  	axp->pid_count++;
>
> @@ -2432,16 +2434,17 @@ void audit_core_dumps(long signr)
>  	ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
>  	audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u",
>  			auid, current->uid, current->gid, sessionid);
> -	selinux_get_task_sid(current, &sid);
> +	security_task_getsecid(current, &sid);
>  	if (sid) {
>  		char *ctx = NULL;
>  		u32 len;
>
> -		if (selinux_sid_to_string(sid, &ctx, &len))
> +		if (security_secid_to_secctx(sid, &ctx, &len))
>  			audit_log_format(ab, " ssid=%u", sid);
> -		else
> +		else {
>  			audit_log_format(ab, " subj=%s", ctx);
> -		kfree(ctx);
> +			security_release_secctx(ctx, len);
> +		}
>  	}
>  	audit_log_format(ab, " pid=%d comm=", current->pid);
>  	audit_log_untrustedstring(ab, current->comm);



-- 
paul moore
linux security @ hp