Re: [PATCH v38 08/39] LSM: Infrastructure management of the sock security

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 <paul(a)paul-moore.com&gt; Reviewed-by: Kees Cook <keescook(a)chromium.org&gt; Reviewed-by: John Johansen <john.johansen(a)canonical.com&gt; Acked-by: Stephen Smalley <stephen.smalley.work(a)gmail.com&gt; Signed-off-by: Casey Schaufler <casey(a)schaufler-ca.com&gt; --- 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 | 82 +++++++++++++++---------------- security/selinux/include/objsec.h | 5 ++ security/selinux/netlabel.c | 23 ++++----- security/smack/smack.h | 5 ++ security/smack/smack_lsm.c | 66 ++++++++++++------------- security/smack/smack_netfilter.c | 4 +- 11 files changed, 146 insertions(+), 122 deletions(-) diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h index ded76db3f523..b266d0826278 100644 --- a/include/linux/lsm_hooks.h +++ b/include/linux/lsm_hooks.h @@ -1625,6 +1625,7 @@ struct lsm_blob_sizes { int lbs_cred; int lbs_file; int lbs_inode; + int lbs_sock; int lbs_superblock; int lbs_ipc; int lbs_msg_msg; diff --git a/security/apparmor/include/net.h b/security/apparmor/include/net.h index aadb4b29fb66..fac8999ba7a3 100644 --- a/security/apparmor/include/net.h +++ b/security/apparmor/include/net.h @@ -51,7 +51,11 @@ struct aa_sk_ctx { struct aa_label *peer; }; -#define SK_CTX(X) ((X)->sk_security) +static inline struct aa_sk_ctx *aa_sock(const struct sock *sk) +{ + return sk->sk_security + apparmor_blob_sizes.lbs_sock; +} + #define SOCK_ctx(X) SOCK_INODE(X)->i_security #define DEFINE_AUDIT_NET(NAME, OP, SK, F, T, P) \ struct lsm_network_audit NAME ## _net = { .sk = (SK), \ diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c index 40266cc4866c..caad42a0c913 100644 --- a/security/apparmor/lsm.c +++ b/security/apparmor/lsm.c @@ -803,33 +803,15 @@ 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); } /** @@ -838,8 +820,8 @@ 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); @@ -892,7 +874,7 @@ 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); @@ -1077,7 +1059,7 @@ 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; @@ -1090,7 +1072,7 @@ 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; @@ -1174,7 +1156,7 @@ 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(); @@ -1184,7 +1166,7 @@ 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; @@ -1201,6 +1183,7 @@ struct lsm_blob_sizes apparmor_blob_sizes __lsm_ro_after_init = { .lbs_cred = sizeof(struct aa_task_ctx *), .lbs_file = sizeof(struct aa_file_ctx), .lbs_task = sizeof(struct aa_task_ctx), + .lbs_sock = sizeof(struct aa_sk_ctx), }; static struct lsm_id apparmor_lsmid __lsm_ro_after_init = { @@ -1243,7 +1226,6 @@ static struct security_hook_list apparmor_hooks[] __lsm_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), @@ -1809,7 +1791,7 @@ 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; diff --git a/security/apparmor/net.c b/security/apparmor/net.c index 7efe4d17273d..b336e23a4467 100644 --- a/security/apparmor/net.c +++ b/security/apparmor/net.c @@ -145,7 +145,7 @@ int aa_af_perm(struct aa_label *label, const char *op, u32 request, u16 family, static int aa_label_sk_perm(struct aa_label *label, 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); diff --git a/security/security.c b/security/security.c index b916469388b0..7a604a74716a 100644 --- a/security/security.c +++ b/security/security.c @@ -30,6 +30,7 @@ #include <linux/msg.h> #include <uapi/linux/lsm.h> #include <net/flow.h> +#include <net/sock.h> #define MAX_LSM_EVM_XATTR 2 @@ -207,6 +208,7 @@ 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); } @@ -349,6 +351,7 @@ 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); @@ -678,6 +681,28 @@ static int lsm_msg_msg_alloc(struct msg_msg *mp) return 0; } +/** + * 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)