 bba14de987
			
		
	
	
	bba14de987
	
	
	
		
			
			Lower SCM_MAX_FD from 255 to 253 so that allocations for scm_fp_list are
halved. (commit f8d570a4 added two pointers in this structure)
scm_fp_dup() should not copy whole structure (and trigger kmemcheck
warnings), but only the used part. While we are at it, only allocate
needed size.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
		
	
			
		
			
				
	
	
		
			130 lines
		
	
	
	
		
			3.2 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			130 lines
		
	
	
	
		
			3.2 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| #ifndef __LINUX_NET_SCM_H
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| #define __LINUX_NET_SCM_H
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| 
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| #include <linux/limits.h>
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| #include <linux/net.h>
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| #include <linux/security.h>
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| #include <linux/pid.h>
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| #include <linux/nsproxy.h>
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| 
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| /* Well, we should have at least one descriptor open
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|  * to accept passed FDs 8)
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|  */
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| #define SCM_MAX_FD	253
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| 
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| struct scm_fp_list {
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| 	struct list_head	list;
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| 	short			count;
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| 	short			max;
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| 	struct file		*fp[SCM_MAX_FD];
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| };
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| 
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| struct scm_cookie {
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| 	struct pid		*pid;		/* Skb credentials */
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| 	const struct cred	*cred;
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| 	struct scm_fp_list	*fp;		/* Passed files		*/
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| 	struct ucred		creds;		/* Skb credentials	*/
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| #ifdef CONFIG_SECURITY_NETWORK
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| 	u32			secid;		/* Passed security ID 	*/
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| #endif
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| };
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| 
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| extern void scm_detach_fds(struct msghdr *msg, struct scm_cookie *scm);
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| extern void scm_detach_fds_compat(struct msghdr *msg, struct scm_cookie *scm);
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| extern int __scm_send(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm);
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| extern void __scm_destroy(struct scm_cookie *scm);
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| extern struct scm_fp_list * scm_fp_dup(struct scm_fp_list *fpl);
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| 
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| #ifdef CONFIG_SECURITY_NETWORK
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| static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
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| {
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| 	security_socket_getpeersec_dgram(sock, NULL, &scm->secid);
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| }
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| #else
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| static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
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| { }
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| #endif /* CONFIG_SECURITY_NETWORK */
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| 
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| static __inline__ void scm_set_cred(struct scm_cookie *scm,
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| 				    struct pid *pid, const struct cred *cred)
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| {
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| 	scm->pid  = get_pid(pid);
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| 	scm->cred = get_cred(cred);
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| 	cred_to_ucred(pid, cred, &scm->creds);
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| }
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| 
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| static __inline__ void scm_destroy_cred(struct scm_cookie *scm)
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| {
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| 	put_pid(scm->pid);
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| 	scm->pid  = NULL;
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| 
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| 	if (scm->cred)
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| 		put_cred(scm->cred);
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| 	scm->cred = NULL;
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| }
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| 
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| static __inline__ void scm_destroy(struct scm_cookie *scm)
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| {
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| 	scm_destroy_cred(scm);
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| 	if (scm && scm->fp)
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| 		__scm_destroy(scm);
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| }
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| 
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| static __inline__ int scm_send(struct socket *sock, struct msghdr *msg,
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| 			       struct scm_cookie *scm)
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| {
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| 	scm_set_cred(scm, task_tgid(current), current_cred());
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| 	scm->fp = NULL;
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| 	unix_get_peersec_dgram(sock, scm);
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| 	if (msg->msg_controllen <= 0)
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| 		return 0;
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| 	return __scm_send(sock, msg, scm);
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| }
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| 
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| #ifdef CONFIG_SECURITY_NETWORK
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| static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
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| {
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| 	char *secdata;
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| 	u32 seclen;
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| 	int err;
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| 
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| 	if (test_bit(SOCK_PASSSEC, &sock->flags)) {
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| 		err = security_secid_to_secctx(scm->secid, &secdata, &seclen);
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| 
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| 		if (!err) {
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| 			put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
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| 			security_release_secctx(secdata, seclen);
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| 		}
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| 	}
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| }
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| #else
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| static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
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| { }
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| #endif /* CONFIG_SECURITY_NETWORK */
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| 
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| static __inline__ void scm_recv(struct socket *sock, struct msghdr *msg,
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| 				struct scm_cookie *scm, int flags)
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| {
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| 	if (!msg->msg_control) {
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| 		if (test_bit(SOCK_PASSCRED, &sock->flags) || scm->fp)
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| 			msg->msg_flags |= MSG_CTRUNC;
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| 		scm_destroy(scm);
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| 		return;
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| 	}
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| 
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| 	if (test_bit(SOCK_PASSCRED, &sock->flags))
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| 		put_cmsg(msg, SOL_SOCKET, SCM_CREDENTIALS, sizeof(scm->creds), &scm->creds);
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| 
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| 	scm_destroy_cred(scm);
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| 
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| 	scm_passec(sock, msg, scm);
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| 
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| 	if (!scm->fp)
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| 		return;
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| 	
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| 	scm_detach_fds(msg, scm);
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| }
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| 
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| 
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| #endif /* __LINUX_NET_SCM_H */
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| 
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