Commit 5a287d3d authored by Ondrej Mosnacek's avatar Ondrej Mosnacek Committed by Paul Moore
Browse files

lsm: fix default return value of the socket_getpeersec_*() hooks 



For these hooks the true "neutral" value is -EOPNOTSUPP, which is
currently what is returned when no LSM provides this hook and what LSMs
return when there is no security context set on the socket. Correct the
value in <linux/lsm_hooks.h> and adjust the dispatch functions in
security/security.c to avoid issues when the BPF LSM is enabled.

Cc: stable@vger.kernel.org
Fixes: 98e828a0 ("security: Refactor declaration of LSM hooks")
Signed-off-by: default avatarOndrej Mosnacek <omosnace@redhat.com>
[PM: subject line tweak]
Signed-off-by: default avatarPaul Moore <paul@paul-moore.com>
parent 99b817c1

include/linux/lsm_hook_defs.h

+2 −2
Original line number Diff line number Diff line
@@ -315,9 +315,9 @@ LSM_HOOK(int, 0, socket_getsockopt, struct socket *sock, int level, int optname) 
LSM_HOOK(int, 0, socket_setsockopt, struct socket *sock, int level, int optname)

LSM_HOOK(int, 0, socket_shutdown, struct socket *sock, int how)

LSM_HOOK(int, 0, socket_sock_rcv_skb, struct sock *sk, struct sk_buff *skb)

LSM_HOOK(int, 0, socket_getpeersec_stream, struct socket *sock,

LSM_HOOK(int, -ENOPROTOOPT, socket_getpeersec_stream, struct socket *sock,

	 sockptr_t optval, sockptr_t optlen, unsigned int len)

LSM_HOOK(int, 0, socket_getpeersec_dgram, struct socket *sock,

LSM_HOOK(int, -ENOPROTOOPT, socket_getpeersec_dgram, struct socket *sock,

	 struct sk_buff *skb, u32 *secid)

LSM_HOOK(int, 0, sk_alloc_security, struct sock *sk, int family, gfp_t priority)

LSM_HOOK(void, LSM_RET_VOID, sk_free_security, struct sock *sk)

security/security.c

+27 −4
Original line number Diff line number Diff line
@@ -4624,8 +4624,20 @@ EXPORT_SYMBOL(security_sock_rcv_skb); 
int security_socket_getpeersec_stream(struct socket *sock, sockptr_t optval,

				      sockptr_t optlen, unsigned int len)

{

	return call_int_hook(socket_getpeersec_stream, -ENOPROTOOPT, sock,

			     optval, optlen, len);

	struct security_hook_list *hp;

	int rc;



	/*

	 * Only one module will provide a security context.

	 */

	hlist_for_each_entry(hp, &security_hook_heads.socket_getpeersec_stream,

			     list) {

		rc = hp->hook.socket_getpeersec_stream(sock, optval, optlen,

						       len);

		if (rc != LSM_RET_DEFAULT(socket_getpeersec_stream))

			return rc;

	}

	return LSM_RET_DEFAULT(socket_getpeersec_stream);

}



/**
@@ -4645,8 +4657,19 @@ int security_socket_getpeersec_stream(struct socket *sock, sockptr_t optval, 
int security_socket_getpeersec_dgram(struct socket *sock,

				     struct sk_buff *skb, u32 *secid)

{

	return call_int_hook(socket_getpeersec_dgram, -ENOPROTOOPT, sock,

			     skb, secid);

	struct security_hook_list *hp;

	int rc;



	/*

	 * Only one module will provide a security context.

	 */

	hlist_for_each_entry(hp, &security_hook_heads.socket_getpeersec_dgram,

			     list) {

		rc = hp->hook.socket_getpeersec_dgram(sock, skb, secid);

		if (rc != LSM_RET_DEFAULT(socket_getpeersec_dgram))

			return rc;

	}

	return LSM_RET_DEFAULT(socket_getpeersec_dgram);

}

EXPORT_SYMBOL(security_socket_getpeersec_dgram);