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FAILED: patch "[PATCH] selinux: avoid sk_socket dereference in" failed to apply to 6.6-stable tree

PATCH New [email protected] 2 participants 3 messages Jul 20 – Jul 23

Subsystems (2)
Stable branch SELinux security module
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[email protected]

author maintainer
#0 lore raw

The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 56acfeb10019e200ab6787d01f8d7cbe0f01526f
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026072005-statutory-bonus-bc65@gregkh' --subject-prefix 'PATCH 6.6.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 56acfeb10019e200ab6787d01f8d7cbe0f01526f Mon Sep 17 00:00:00 2001
From: Tristan Madani <[email protected]>
Date: Thu, 25 Jun 2026 23:53:36 +0000
Subject: [PATCH] selinux: avoid sk_socket dereference in
selinux_sctp_bind_connect()

selinux_sctp_bind_connect() dereferences sk->sk_socket to pass a struct socket * to selinux_socket_bind() and selinux_socket_connect_helper(). However, when the hook is invoked from the ASCONF softirq path (sctp_process_asconf), there is no file reference guaranteeing that sk->sk_socket is non-NULL. The setsockopt callers (bindx, connectx, set_primary, sendmsg connect) hold a file reference and are not affected.

Both selinux_socket_bind() and selinux_socket_connect_helper() immediately resolve sock->sk, never using the struct socket * for anything else. Refactor the inner logic into helpers that take a struct sock * directly so that selinux_sctp_bind_connect() never needs to touch sk->sk_socket at all.

Cc [email protected]
Fixes d452930fd3b9 ("selinux: Add SCTP support")
Suggested-by Stephen Smalley <[email protected]>
Signed-off-by Tristan Madani <[email protected]>
Reviewed-by Stephen Smalley <[email protected]>
Tested-by Stephen Smalley <[email protected]>
Signed-off-by Paul Moore <[email protected]>
security/selinux/hooks.c +10 -9
index c4677ce89399..70a3388c047d 100644
@@ -4994,9 +4994,8 @@ static int selinux_socket_socketpair(struct socket *socka,
    Need to determine whether we should perform a name_bind
    permission check between the socket and the port number. */
 
-static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
+static int __selinux_socket_bind(struct sock *sk, struct sockaddr *address, int addrlen)
 {
-	struct sock *sk = sock->sk;
 	struct sk_security_struct *sksec = selinux_sock(sk);
 	u16 family;
 	int err;

@@ -5126,13 +5125,17 @@ static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, in
 	return -EAFNOSUPPORT;
 }
 
+static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
+{
+	return __selinux_socket_bind(sock->sk, address, addrlen);
+}
+
 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
  * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
  */
-static int selinux_socket_connect_helper(struct socket *sock,
+static int selinux_socket_connect_helper(struct sock *sk,
 					 struct sockaddr *address, int addrlen)
 {
-	struct sock *sk = sock->sk;
 	struct sk_security_struct *sksec = selinux_sock(sk);
 	int err;
 

@@ -5221,7 +5224,7 @@ static int selinux_socket_connect(struct socket *sock,
 	int err;
 	struct sock *sk = sock->sk;
 
-	err = selinux_socket_connect_helper(sock, address, addrlen);
+	err = selinux_socket_connect_helper(sk, address, addrlen);
 	if (err)
 		return err;
 

@@ -5723,13 +5726,11 @@ static int selinux_sctp_bind_connect(struct sock *sk, int optname,
 	int len, err = 0, walk_size = 0;
 	void *addr_buf;
 	struct sockaddr *addr;
-	struct socket *sock;
 
 	if (!selinux_policycap_extsockclass())
 		return 0;
 
 	/* Process one or more addresses that may be IPv4 or IPv6 */
-	sock = sk->sk_socket;
 	addr_buf = address;
 
 	while (walk_size < addrlen) {

@@ -5758,14 +5759,14 @@ static int selinux_sctp_bind_connect(struct sock *sk, int optname,
 		case SCTP_PRIMARY_ADDR:
 		case SCTP_SET_PEER_PRIMARY_ADDR:
 		case SCTP_SOCKOPT_BINDX_ADD:
-			err = selinux_socket_bind(sock, addr, len);
+			err = __selinux_socket_bind(sk, addr, len);
 			break;
 		/* Connect checks */
 		case SCTP_SOCKOPT_CONNECTX:
 		case SCTP_PARAM_SET_PRIMARY:
 		case SCTP_PARAM_ADD_IP:
 		case SCTP_SENDMSG_CONNECT:
-			err = selinux_socket_connect_helper(sock, addr, len);
+			err = selinux_socket_connect_helper(sk, addr, len);
 			if (err)
 				return err;
maintainer
#1 lore raw

PATCH 1/2 lsm: infrastructure management of the sock security

From: Casey Schaufler <[email protected]>

[ Upstream commit 2aff9d20d50ac45dd13a013ef5231f4fb8912356 ]

Move management of the sock->sk_security blob out of the individual security modules and into the security infrastructure. Instead of allocating the blobs from within the modules the modules tell the infrastructure how much space is required, and the space is allocated there.

Acked-by Paul Moore <[email protected]>
Reviewed-by Kees Cook <[email protected]>
Reviewed-by John Johansen <[email protected]>
Acked-by Stephen Smalley <[email protected]>
Signed-off-by Casey Schaufler <[email protected]>
[PM: subject tweak]
Signed-off-by Paul Moore <[email protected]>

Stable-dep-of: 56acfeb10019 ("selinux: avoid sk_socket dereference in selinux_sctp_bind_connect()")

Signed-off-by Sasha Levin <[email protected]>
---
 include/linux/lsm_hooks.h         |  1 +
 security/apparmor/include/net.h   |  6 ++-
 security/apparmor/lsm.c           | 38 ++++-----------
 security/apparmor/net.c           |  2 +-
 security/security.c               | 36 +++++++++++++-
 security/selinux/hooks.c          | 80 ++++++++++++++-----------------
 security/selinux/include/objsec.h |  5 ++
 security/selinux/netlabel.c       | 23 ++++-----
 security/smack/smack.h            |  5 ++
 security/smack/smack_lsm.c        | 70 +++++++++++++--------------
 security/smack/smack_netfilter.c  |  4 +-
 11 files changed, 146 insertions(+), 124 deletions(-)
include/linux/lsm_hooks.h +1 -0
index 3b56b60195ceb9..2365b4d6185733 100644
@@ -61,6 +61,7 @@ struct lsm_blob_sizes {
 	int	lbs_file;
 	int lbs_backing_file;
 	int	lbs_inode;
+	int	lbs_sock;
 	int	lbs_superblock;
 	int	lbs_ipc;
 	int	lbs_msg_msg;
security/apparmor/include/net.h +5 -1
index aa8515af677f0e..97ea4d0c607ce1 100644
@@ -51,8 +51,12 @@ struct aa_sk_ctx {
 	struct aa_label *peer;
 };
 
-#define SK_CTX(X) ((X)->sk_security)
 #define SOCK_ctx(X) SOCK_INODE(X)->i_security
+static inline struct aa_sk_ctx *aa_sock(const struct sock *sk)
+{
+	return sk->sk_security + apparmor_blob_sizes.lbs_sock;
+}
+
 #define DEFINE_AUDIT_NET(NAME, OP, SK, F, T, P)				  \
 	struct lsm_network_audit NAME ## _net = { .sk = (SK),		  \
 						  .family = (F)};	  \
security/apparmor/lsm.c +10 -28
index 79d0a9c1a99b11..7daf142b99de01 100644
@@ -850,33 +850,15 @@ static int apparmor_task_kill(struct task_struct *target, struct kernel_siginfo
 	return error;
 }
 
-/**
- * apparmor_sk_alloc_security - allocate and attach the sk_security field
- */
-static int apparmor_sk_alloc_security(struct sock *sk, int family, gfp_t flags)
-{
-	struct aa_sk_ctx *ctx;
-
-	ctx = kzalloc(sizeof(*ctx), flags);
-	if (!ctx)
-		return -ENOMEM;
-
-	SK_CTX(sk) = ctx;
-
-	return 0;
-}
-
 /**
  * apparmor_sk_free_security - free the sk_security field
  */
 static void apparmor_sk_free_security(struct sock *sk)
 {
-	struct aa_sk_ctx *ctx = SK_CTX(sk);
+	struct aa_sk_ctx *ctx = aa_sock(sk);
 
-	SK_CTX(sk) = NULL;
 	aa_put_label(ctx->label);
 	aa_put_label(ctx->peer);
-	kfree(ctx);
 }
 
 /**

@@ -885,8 +867,8 @@ static void apparmor_sk_free_security(struct sock *sk)
 static void apparmor_sk_clone_security(const struct sock *sk,
 				       struct sock *newsk)
 {
-	struct aa_sk_ctx *ctx = SK_CTX(sk);
-	struct aa_sk_ctx *new = SK_CTX(newsk);
+	struct aa_sk_ctx *ctx = aa_sock(sk);
+	struct aa_sk_ctx *new = aa_sock(newsk);
 
 	if (new->label)
 		aa_put_label(new->label);

@@ -940,7 +922,7 @@ static int apparmor_socket_post_create(struct socket *sock, int family,
 		label = aa_get_current_label();
 
 	if (sock->sk) {
-		struct aa_sk_ctx *ctx = SK_CTX(sock->sk);
+		struct aa_sk_ctx *ctx = aa_sock(sock->sk);
 
 		aa_put_label(ctx->label);
 		ctx->label = aa_get_label(label);

@@ -1139,7 +1121,7 @@ static int apparmor_socket_shutdown(struct socket *sock, int how)
  */
 static int apparmor_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
 {
-	struct aa_sk_ctx *ctx = SK_CTX(sk);
+	struct aa_sk_ctx *ctx = aa_sock(sk);
 
 	if (!skb->secmark)
 		return 0;

@@ -1159,7 +1141,7 @@ static int apparmor_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
 
 static struct aa_label *sk_peer_label(struct sock *sk)
 {
-	struct aa_sk_ctx *ctx = SK_CTX(sk);
+	struct aa_sk_ctx *ctx = aa_sock(sk);
 
 	if (ctx->peer)
 		return ctx->peer;

@@ -1240,7 +1222,7 @@ static int apparmor_socket_getpeersec_dgram(struct socket *sock,
  */
 static void apparmor_sock_graft(struct sock *sk, struct socket *parent)
 {
-	struct aa_sk_ctx *ctx = SK_CTX(sk);
+	struct aa_sk_ctx *ctx = aa_sock(sk);
 
 	if (!ctx->label)
 		ctx->label = aa_get_current_label();

@@ -1250,7 +1232,7 @@ static void apparmor_sock_graft(struct sock *sk, struct socket *parent)
 static int apparmor_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
 				      struct request_sock *req)
 {
-	struct aa_sk_ctx *ctx = SK_CTX(sk);
+	struct aa_sk_ctx *ctx = aa_sock(sk);
 
 	if (!skb->secmark)
 		return 0;

@@ -1267,6 +1249,7 @@ struct lsm_blob_sizes apparmor_blob_sizes __ro_after_init = {
 	.lbs_cred = sizeof(struct aa_label *),
 	.lbs_file = sizeof(struct aa_file_ctx),
 	.lbs_task = sizeof(struct aa_task_ctx),
+	.lbs_sock = sizeof(struct aa_sk_ctx),
 };
 
 static struct security_hook_list apparmor_hooks[] __ro_after_init = {

@@ -1305,7 +1288,6 @@ static struct security_hook_list apparmor_hooks[] __ro_after_init = {
 	LSM_HOOK_INIT(getprocattr, apparmor_getprocattr),
 	LSM_HOOK_INIT(setprocattr, apparmor_setprocattr),
 
-	LSM_HOOK_INIT(sk_alloc_security, apparmor_sk_alloc_security),
 	LSM_HOOK_INIT(sk_free_security, apparmor_sk_free_security),
 	LSM_HOOK_INIT(sk_clone_security, apparmor_sk_clone_security),
 

@@ -1864,7 +1846,7 @@ static unsigned int apparmor_ip_postroute(void *priv,
 	if (sk == NULL)
 		return NF_ACCEPT;
 
-	ctx = SK_CTX(sk);
+	ctx = aa_sock(sk);
 	if (!apparmor_secmark_check(ctx->label, OP_SENDMSG, AA_MAY_SEND,
 				    skb->secmark, sk))
 		return NF_ACCEPT;
security/apparmor/net.c +1 -1
index 3e632700d06fb3..f6f749191f6017 100644
@@ -151,7 +151,7 @@ static int aa_label_sk_perm(const struct cred *subj_cred,
 			    const char *op, u32 request,
 			    struct sock *sk)
 {
-	struct aa_sk_ctx *ctx = SK_CTX(sk);
+	struct aa_sk_ctx *ctx = aa_sock(sk);
 	int error = 0;
 
 	AA_BUG(!label);
security/security.c +35 -1
index 4b61766c3d27bd..d90507fd008e7c 100644
@@ -30,6 +30,7 @@
 #include <linux/string.h>
 #include <linux/msg.h>
 #include <net/flow.h>
+#include <net/sock.h>
 
 /* How many LSMs were built into the kernel? */
 #define LSM_COUNT (__end_lsm_info - __start_lsm_info)

@@ -212,6 +213,7 @@ static void __init lsm_set_blob_sizes(struct lsm_blob_sizes *needed)
 	lsm_set_blob_size(&needed->lbs_inode, &blob_sizes.lbs_inode);
 	lsm_set_blob_size(&needed->lbs_ipc, &blob_sizes.lbs_ipc);
 	lsm_set_blob_size(&needed->lbs_msg_msg, &blob_sizes.lbs_msg_msg);
+	lsm_set_blob_size(&needed->lbs_sock, &blob_sizes.lbs_sock);
 	lsm_set_blob_size(&needed->lbs_superblock, &blob_sizes.lbs_superblock);
 	lsm_set_blob_size(&needed->lbs_task, &blob_sizes.lbs_task);
 	lsm_set_blob_size(&needed->lbs_xattr_count,

@@ -381,6 +383,7 @@ static void __init ordered_lsm_init(void)
 	init_debug("inode blob size      = %d\n", blob_sizes.lbs_inode);
 	init_debug("ipc blob size        = %d\n", blob_sizes.lbs_ipc);
 	init_debug("msg_msg blob size    = %d\n", blob_sizes.lbs_msg_msg);
+	init_debug("sock blob size       = %d\n", blob_sizes.lbs_sock);
 	init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock);
 	init_debug("task blob size       = %d\n", blob_sizes.lbs_task);
 	init_debug("xattr slots          = %d\n", blob_sizes.lbs_xattr_count);

@@ -4559,6 +4562,28 @@ int security_socket_getpeersec_dgram(struct socket *sock,
 }
 EXPORT_SYMBOL(security_socket_getpeersec_dgram);
 
+/**
+ * lsm_sock_alloc - allocate a composite sock blob
+ * @sock: the sock that needs a blob
+ * @priority: allocation mode
+ *
+ * Allocate the sock blob for all the modules
+ *
+ * Returns 0, or -ENOMEM if memory can't be allocated.
+ */
+static int lsm_sock_alloc(struct sock *sock, gfp_t priority)
+{
+	if (blob_sizes.lbs_sock == 0) {
+		sock->sk_security = NULL;
+		return 0;
+	}
+
+	sock->sk_security = kzalloc(blob_sizes.lbs_sock, priority);
+	if (sock->sk_security == NULL)
+		return -ENOMEM;
+	return 0;
+}
+
 /**
  * security_sk_alloc() - Allocate and initialize a sock's LSM blob
  * @sk: sock

@@ -4572,7 +4597,14 @@ EXPORT_SYMBOL(security_socket_getpeersec_dgram);
  */
 int security_sk_alloc(struct sock *sk, int family, gfp_t priority)
 {
-	return call_int_hook(sk_alloc_security, 0, sk, family, priority);
+	int rc = lsm_sock_alloc(sk, priority);
+
+	if (unlikely(rc))
+		return rc;
+	rc = call_int_hook(sk_alloc_security, 0, sk, family, priority);
+	if (unlikely(rc))
+		security_sk_free(sk);
+	return rc;
 }
 
 /**

@@ -4584,6 +4616,8 @@ int security_sk_alloc(struct sock *sk, int family, gfp_t priority)
 void security_sk_free(struct sock *sk)
 {
 	call_void_hook(sk_free_security, sk);
+	kfree(sk->sk_security);
+	sk->sk_security = NULL;
 }
 
 /**
security/selinux/hooks.c +37 -43

265 lines not on this page · raw message

security/selinux/include/objsec.h +5 -0
index 541933dd295c07..b9c61b2ac482e8 100644
@@ -205,4 +205,9 @@ static inline struct superblock_security_struct *selinux_superblock(
 	return superblock->s_security + selinux_blob_sizes.lbs_superblock;
 }
 
+static inline struct sk_security_struct *selinux_sock(const struct sock *sock)
+{
+	return sock->sk_security + selinux_blob_sizes.lbs_sock;
+}
+
 #endif /* _SELINUX_OBJSEC_H_ */
security/selinux/netlabel.c +12 -11
index 8f182800e41245..e8832726bd8692 100644
@@ -17,6 +17,7 @@
 #include <linux/gfp.h>
 #include <linux/ip.h>
 #include <linux/ipv6.h>
+#include <linux/lsm_hooks.h>
 #include <net/sock.h>
 #include <net/netlabel.h>
 #include <net/ip.h>

@@ -68,7 +69,7 @@ static int selinux_netlbl_sidlookup_cached(struct sk_buff *skb,
 static struct netlbl_lsm_secattr *selinux_netlbl_sock_genattr(struct sock *sk)
 {
 	int rc;
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 	struct netlbl_lsm_secattr *secattr;
 
 	if (sksec->nlbl_secattr != NULL)

@@ -100,7 +101,7 @@ static struct netlbl_lsm_secattr *selinux_netlbl_sock_getattr(
 							const struct sock *sk,
 							u32 sid)
 {
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 	struct netlbl_lsm_secattr *secattr = sksec->nlbl_secattr;
 
 	if (secattr == NULL)

@@ -240,7 +241,7 @@ int selinux_netlbl_skbuff_setsid(struct sk_buff *skb,
 	 * being labeled by it's parent socket, if it is just exit */
 	sk = skb_to_full_sk(skb);
 	if (sk != NULL) {
-		struct sk_security_struct *sksec = sk->sk_security;
+		struct sk_security_struct *sksec = selinux_sock(sk);
 
 		if (sksec->nlbl_state != NLBL_REQSKB)
 			return 0;

@@ -277,7 +278,7 @@ int selinux_netlbl_sctp_assoc_request(struct sctp_association *asoc,
 {
 	int rc;
 	struct netlbl_lsm_secattr secattr;
-	struct sk_security_struct *sksec = asoc->base.sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(asoc->base.sk);
 	struct sockaddr_in addr4;
 	struct sockaddr_in6 addr6;
 

@@ -356,7 +357,7 @@ int selinux_netlbl_inet_conn_request(struct request_sock *req, u16 family)
  */
 void selinux_netlbl_inet_csk_clone(struct sock *sk, u16 family)
 {
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 
 	if (family == PF_INET)
 		sksec->nlbl_state = NLBL_LABELED;

@@ -374,8 +375,8 @@ void selinux_netlbl_inet_csk_clone(struct sock *sk, u16 family)
  */
 void selinux_netlbl_sctp_sk_clone(struct sock *sk, struct sock *newsk)
 {
-	struct sk_security_struct *sksec = sk->sk_security;
-	struct sk_security_struct *newsksec = newsk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
+	struct sk_security_struct *newsksec = selinux_sock(newsk);
 
 	newsksec->nlbl_state = sksec->nlbl_state;
 }

@@ -393,7 +394,7 @@ void selinux_netlbl_sctp_sk_clone(struct sock *sk, struct sock *newsk)
 int selinux_netlbl_socket_post_create(struct sock *sk, u16 family)
 {
 	int rc;
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 	struct netlbl_lsm_secattr *secattr;
 
 	if (family != PF_INET && family != PF_INET6)

@@ -507,7 +508,7 @@ int selinux_netlbl_socket_setsockopt(struct socket *sock,
 {
 	int rc = 0;
 	struct sock *sk = sock->sk;
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 	struct netlbl_lsm_secattr secattr;
 
 	if (selinux_netlbl_option(level, optname) &&

@@ -545,7 +546,7 @@ static int selinux_netlbl_socket_connect_helper(struct sock *sk,
 						struct sockaddr *addr)
 {
 	int rc;
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 	struct netlbl_lsm_secattr *secattr;
 
 	/* connected sockets are allowed to disconnect when the address family

@@ -584,7 +585,7 @@ static int selinux_netlbl_socket_connect_helper(struct sock *sk,
 int selinux_netlbl_socket_connect_locked(struct sock *sk,
 					 struct sockaddr *addr)
 {
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 
 	if (sksec->nlbl_state != NLBL_REQSKB &&
 	    sksec->nlbl_state != NLBL_CONNLABELED)
security/smack/smack.h +5 -0
index 5e4a3c3144dd98..aac0574cdfad30 100644
@@ -361,6 +361,11 @@ static inline struct superblock_smack *smack_superblock(
 	return superblock->s_security + smack_blob_sizes.lbs_superblock;
 }
 
+static inline struct socket_smack *smack_sock(const struct sock *sock)
+{
+	return sock->sk_security + smack_blob_sizes.lbs_sock;
+}
+
 /*
  * Is the directory transmuting?
  */
security/smack/smack_lsm.c +33 -37

243 lines not on this page · raw message

security/smack/smack_netfilter.c +2 -2
index b945c1d3a7431a..bad71b7e648da7 100644
@@ -26,8 +26,8 @@ static unsigned int smack_ip_output(void *priv,
 	struct socket_smack *ssp;
 	struct smack_known *skp;
 
-	if (sk && sk->sk_security) {
-		ssp = sk->sk_security;
+	if (sk) {
+		ssp = smack_sock(sk);
 		skp = ssp->smk_out;
 		skb->secmark = skp->smk_secid;
 	}
Signature · 1 line
2.53.0
maintainer
#2 lore raw

PATCH 2/2 selinux: avoid sk_socket dereference in selinux_sctp_bind_connect()

From: Tristan Madani <[email protected]>

[ Upstream commit 56acfeb10019e200ab6787d01f8d7cbe0f01526f ]

selinux_sctp_bind_connect() dereferences sk->sk_socket to pass a struct socket * to selinux_socket_bind() and selinux_socket_connect_helper(). However, when the hook is invoked from the ASCONF softirq path (sctp_process_asconf), there is no file reference guaranteeing that sk->sk_socket is non-NULL. The setsockopt callers (bindx, connectx, set_primary, sendmsg connect) hold a file reference and are not affected.

Both selinux_socket_bind() and selinux_socket_connect_helper() immediately resolve sock->sk, never using the struct socket * for anything else. Refactor the inner logic into helpers that take a struct sock * directly so that selinux_sctp_bind_connect() never needs to touch sk->sk_socket at all.

Cc [email protected]
Fixes d452930fd3b9 ("selinux: Add SCTP support")
Suggested-by Stephen Smalley <[email protected]>
Signed-off-by Tristan Madani <[email protected]>
Reviewed-by Stephen Smalley <[email protected]>
Tested-by Stephen Smalley <[email protected]>
Signed-off-by Paul Moore <[email protected]>
Signed-off-by Sasha Levin <[email protected]>
---
 security/selinux/hooks.c | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)
security/selinux/hooks.c +10 -9
index ba4e396b93f314..8dd72e7106934c 100644
@@ -4771,9 +4771,8 @@ static int selinux_socket_socketpair(struct socket *socka,
    Need to determine whether we should perform a name_bind
    permission check between the socket and the port number. */
 
-static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
+static int __selinux_socket_bind(struct sock *sk, struct sockaddr *address, int addrlen)
 {
-	struct sock *sk = sock->sk;
 	struct sk_security_struct *sksec = selinux_sock(sk);
 	u16 family;
 	int err;

@@ -4907,13 +4906,17 @@ static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, in
 	return -EAFNOSUPPORT;
 }
 
+static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
+{
+	return __selinux_socket_bind(sock->sk, address, addrlen);
+}
+
 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
  * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
  */
-static int selinux_socket_connect_helper(struct socket *sock,
+static int selinux_socket_connect_helper(struct sock *sk,
 					 struct sockaddr *address, int addrlen)
 {
-	struct sock *sk = sock->sk;
 	struct sk_security_struct *sksec = selinux_sock(sk);
 	int err;
 

@@ -5006,7 +5009,7 @@ static int selinux_socket_connect(struct socket *sock,
 	int err;
 	struct sock *sk = sock->sk;
 
-	err = selinux_socket_connect_helper(sock, address, addrlen);
+	err = selinux_socket_connect_helper(sk, address, addrlen);
 	if (err)
 		return err;
 

@@ -5489,13 +5492,11 @@ static int selinux_sctp_bind_connect(struct sock *sk, int optname,
 	int len, err = 0, walk_size = 0;
 	void *addr_buf;
 	struct sockaddr *addr;
-	struct socket *sock;
 
 	if (!selinux_policycap_extsockclass())
 		return 0;
 
 	/* Process one or more addresses that may be IPv4 or IPv6 */
-	sock = sk->sk_socket;
 	addr_buf = address;
 
 	while (walk_size < addrlen) {

@@ -5524,14 +5525,14 @@ static int selinux_sctp_bind_connect(struct sock *sk, int optname,
 		case SCTP_PRIMARY_ADDR:
 		case SCTP_SET_PEER_PRIMARY_ADDR:
 		case SCTP_SOCKOPT_BINDX_ADD:
-			err = selinux_socket_bind(sock, addr, len);
+			err = __selinux_socket_bind(sk, addr, len);
 			break;
 		/* Connect checks */
 		case SCTP_SOCKOPT_CONNECTX:
 		case SCTP_PARAM_SET_PRIMARY:
 		case SCTP_PARAM_ADD_IP:
 		case SCTP_SENDMSG_CONNECT:
-			err = selinux_socket_connect_helper(sock, addr, len);
+			err = selinux_socket_connect_helper(sk, addr, len);
 			if (err)
 				return err;
Signature · 1 line
2.53.0