recursion in __scm_destroy() will be cut by delaying final fput() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
		
			
				
	
	
		
			128 lines
		
	
	
	
		
			3.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			128 lines
		
	
	
	
		
			3.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
#ifndef __LINUX_NET_SCM_H
 | 
						|
#define __LINUX_NET_SCM_H
 | 
						|
 | 
						|
#include <linux/limits.h>
 | 
						|
#include <linux/net.h>
 | 
						|
#include <linux/security.h>
 | 
						|
#include <linux/pid.h>
 | 
						|
#include <linux/nsproxy.h>
 | 
						|
 | 
						|
/* Well, we should have at least one descriptor open
 | 
						|
 * to accept passed FDs 8)
 | 
						|
 */
 | 
						|
#define SCM_MAX_FD	253
 | 
						|
 | 
						|
struct scm_fp_list {
 | 
						|
	short			count;
 | 
						|
	short			max;
 | 
						|
	struct file		*fp[SCM_MAX_FD];
 | 
						|
};
 | 
						|
 | 
						|
struct scm_cookie {
 | 
						|
	struct pid		*pid;		/* Skb credentials */
 | 
						|
	const struct cred	*cred;
 | 
						|
	struct scm_fp_list	*fp;		/* Passed files		*/
 | 
						|
	struct ucred		creds;		/* Skb credentials	*/
 | 
						|
#ifdef CONFIG_SECURITY_NETWORK
 | 
						|
	u32			secid;		/* Passed security ID 	*/
 | 
						|
#endif
 | 
						|
};
 | 
						|
 | 
						|
extern void scm_detach_fds(struct msghdr *msg, struct scm_cookie *scm);
 | 
						|
extern void scm_detach_fds_compat(struct msghdr *msg, struct scm_cookie *scm);
 | 
						|
extern int __scm_send(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm);
 | 
						|
extern void __scm_destroy(struct scm_cookie *scm);
 | 
						|
extern struct scm_fp_list * scm_fp_dup(struct scm_fp_list *fpl);
 | 
						|
 | 
						|
#ifdef CONFIG_SECURITY_NETWORK
 | 
						|
static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
 | 
						|
{
 | 
						|
	security_socket_getpeersec_dgram(sock, NULL, &scm->secid);
 | 
						|
}
 | 
						|
#else
 | 
						|
static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
 | 
						|
{ }
 | 
						|
#endif /* CONFIG_SECURITY_NETWORK */
 | 
						|
 | 
						|
static __inline__ void scm_set_cred(struct scm_cookie *scm,
 | 
						|
				    struct pid *pid, const struct cred *cred)
 | 
						|
{
 | 
						|
	scm->pid  = get_pid(pid);
 | 
						|
	scm->cred = cred ? get_cred(cred) : NULL;
 | 
						|
	cred_to_ucred(pid, cred, &scm->creds);
 | 
						|
}
 | 
						|
 | 
						|
static __inline__ void scm_destroy_cred(struct scm_cookie *scm)
 | 
						|
{
 | 
						|
	put_pid(scm->pid);
 | 
						|
	scm->pid  = NULL;
 | 
						|
 | 
						|
	if (scm->cred)
 | 
						|
		put_cred(scm->cred);
 | 
						|
	scm->cred = NULL;
 | 
						|
}
 | 
						|
 | 
						|
static __inline__ void scm_destroy(struct scm_cookie *scm)
 | 
						|
{
 | 
						|
	scm_destroy_cred(scm);
 | 
						|
	if (scm && scm->fp)
 | 
						|
		__scm_destroy(scm);
 | 
						|
}
 | 
						|
 | 
						|
static __inline__ int scm_send(struct socket *sock, struct msghdr *msg,
 | 
						|
			       struct scm_cookie *scm)
 | 
						|
{
 | 
						|
	memset(scm, 0, sizeof(*scm));
 | 
						|
	unix_get_peersec_dgram(sock, scm);
 | 
						|
	if (msg->msg_controllen <= 0)
 | 
						|
		return 0;
 | 
						|
	return __scm_send(sock, msg, scm);
 | 
						|
}
 | 
						|
 | 
						|
#ifdef CONFIG_SECURITY_NETWORK
 | 
						|
static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
 | 
						|
{
 | 
						|
	char *secdata;
 | 
						|
	u32 seclen;
 | 
						|
	int err;
 | 
						|
 | 
						|
	if (test_bit(SOCK_PASSSEC, &sock->flags)) {
 | 
						|
		err = security_secid_to_secctx(scm->secid, &secdata, &seclen);
 | 
						|
 | 
						|
		if (!err) {
 | 
						|
			put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
 | 
						|
			security_release_secctx(secdata, seclen);
 | 
						|
		}
 | 
						|
	}
 | 
						|
}
 | 
						|
#else
 | 
						|
static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
 | 
						|
{ }
 | 
						|
#endif /* CONFIG_SECURITY_NETWORK */
 | 
						|
 | 
						|
static __inline__ void scm_recv(struct socket *sock, struct msghdr *msg,
 | 
						|
				struct scm_cookie *scm, int flags)
 | 
						|
{
 | 
						|
	if (!msg->msg_control) {
 | 
						|
		if (test_bit(SOCK_PASSCRED, &sock->flags) || scm->fp)
 | 
						|
			msg->msg_flags |= MSG_CTRUNC;
 | 
						|
		scm_destroy(scm);
 | 
						|
		return;
 | 
						|
	}
 | 
						|
 | 
						|
	if (test_bit(SOCK_PASSCRED, &sock->flags))
 | 
						|
		put_cmsg(msg, SOL_SOCKET, SCM_CREDENTIALS, sizeof(scm->creds), &scm->creds);
 | 
						|
 | 
						|
	scm_destroy_cred(scm);
 | 
						|
 | 
						|
	scm_passec(sock, msg, scm);
 | 
						|
 | 
						|
	if (!scm->fp)
 | 
						|
		return;
 | 
						|
	
 | 
						|
	scm_detach_fds(msg, scm);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
#endif /* __LINUX_NET_SCM_H */
 | 
						|
 |