[PATCH v2 16/25] LSM: Ensure the correct LSM context releaser
Casey Schaufler
casey at schaufler-ca.com
Tue Jun 18 23:05:42 UTC 2019
Add a new lsmcontext data structure to hold all the information
about a "security context", including the string, its size and
which LSM allocated the string. The allocation information is
necessary because LSMs have different policies regarding the
lifecycle of these strings. SELinux allocates and destroys
them on each use, whereas Smack provides a pointer to an entry
in a list that never goes away.
Change the security_release_secctx() interface to use the
lsmcontext and call only the appropiate LSM hook. Change
the callers of security_release_secctx() to provide the
correct type of data, introducing scaffolding where required.
Signed-off-by: Casey Schaufler <casey at schaufler-ca.com>
---
drivers/android/binder.c | 10 +++++--
fs/kernfs/dir.c | 9 ++++--
fs/kernfs/inode.c | 7 +++--
fs/nfs/nfs4proc.c | 8 ++++--
fs/nfsd/nfs4xdr.c | 7 +++--
include/linux/security.h | 37 +++++++++++++++++++++++--
include/net/scm.h | 4 ++-
kernel/audit.c | 14 +++++++---
kernel/auditsc.c | 12 ++++++--
net/ipv4/ip_sockglue.c | 4 ++-
net/netfilter/nf_conntrack_netlink.c | 4 ++-
net/netfilter/nf_conntrack_standalone.c | 4 ++-
net/netfilter/nfnetlink_queue.c | 13 ++++++---
net/netlabel/netlabel_unlabeled.c | 19 ++++++++++---
net/netlabel/netlabel_user.c | 4 ++-
security/security.c | 12 +++++---
security/smack/smack_lsm.c | 14 +++++++---
17 files changed, 140 insertions(+), 42 deletions(-)
diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index 9eb790200fba..f11b5ca5bc30 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -2876,6 +2876,7 @@ static void binder_transaction(struct binder_proc *proc,
int t_debug_id = atomic_inc_return(&binder_last_id);
char *secctx = NULL;
u32 secctx_sz = 0;
+ struct lsmcontext scaff; /* scaffolding */
e = binder_transaction_log_add(&binder_transaction_log);
e->debug_id = t_debug_id;
@@ -3158,7 +3159,8 @@ static void binder_transaction(struct binder_proc *proc,
binder_alloc_copy_to_buffer(&target_proc->alloc,
t->buffer, buf_offset,
secctx, secctx_sz);
- security_release_secctx(secctx, secctx_sz);
+ lsmcontext_init(&scaff, secctx, secctx_sz, 0);
+ security_release_secctx(&scaff);
secctx = NULL;
}
t->buffer->debug_id = t->debug_id;
@@ -3479,8 +3481,10 @@ static void binder_transaction(struct binder_proc *proc,
t->buffer->transaction = NULL;
binder_alloc_free_buf(&target_proc->alloc, t->buffer);
err_binder_alloc_buf_failed:
- if (secctx)
- security_release_secctx(secctx, secctx_sz);
+ if (secctx) {
+ lsmcontext_init(&scaff, secctx, secctx_sz, 0);
+ security_release_secctx(&scaff);
+ }
err_get_secctx_failed:
kfree(tcomplete);
binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c
index b84d635567d3..92afad387237 100644
--- a/fs/kernfs/dir.c
+++ b/fs/kernfs/dir.c
@@ -532,9 +532,12 @@ void kernfs_put(struct kernfs_node *kn)
kfree_const(kn->name);
if (kn->iattr) {
- if (kn->iattr->ia_secdata)
- security_release_secctx(kn->iattr->ia_secdata,
- kn->iattr->ia_secdata_len);
+ struct lsmcontext scaff; /* scaffolding */
+ if (kn->iattr->ia_secdata) {
+ lsmcontext_init(&scaff, kn->iattr->ia_secdata,
+ kn->iattr->ia_secdata_len, 0);
+ security_release_secctx(&scaff);
+ }
simple_xattrs_free(&kn->iattr->xattrs);
kmem_cache_free(kernfs_iattrs_cache, kn->iattr);
}
diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c
index 0c1fd945ce42..02cde9dac5ee 100644
--- a/fs/kernfs/inode.c
+++ b/fs/kernfs/inode.c
@@ -349,6 +349,7 @@ static int kernfs_security_xattr_set(const struct xattr_handler *handler,
{
struct kernfs_node *kn = inode->i_private;
struct kernfs_iattrs *attrs;
+ struct lsmcontext context;
void *secdata;
u32 secdata_len = 0;
int error;
@@ -368,8 +369,10 @@ static int kernfs_security_xattr_set(const struct xattr_handler *handler,
error = kernfs_node_setsecdata(attrs, &secdata, &secdata_len);
mutex_unlock(&kernfs_mutex);
- if (secdata)
- security_release_secctx(secdata, secdata_len);
+ if (secdata) {
+ lsmcontext_init(&context, secdata, secdata_len, 0);
+ security_release_secctx(&context);
+ }
return error;
}
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 4dbb0ee23432..af1c0db29c39 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -131,8 +131,12 @@ nfs4_label_init_security(struct inode *dir, struct dentry *dentry,
static inline void
nfs4_label_release_security(struct nfs4_label *label)
{
- if (label)
- security_release_secctx(label->label, label->len);
+ struct lsmcontext scaff; /* scaffolding */
+
+ if (label) {
+ lsmcontext_init(&scaff, label->label, label->len, 0);
+ security_release_secctx(&scaff);
+ }
}
static inline u32 *nfs4_bitmask(struct nfs_server *server, struct nfs4_label *label)
{
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 3de42a729093..bb3db033e144 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -2420,6 +2420,7 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
__be32 status;
int err;
struct nfs4_acl *acl = NULL;
+ struct lsmcontext scaff; /* scaffolding */
void *context = NULL;
int contextlen;
bool contextsupport = false;
@@ -2919,8 +2920,10 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
out:
#ifdef CONFIG_NFSD_V4_SECURITY_LABEL
- if (context)
- security_release_secctx(context, contextlen);
+ if (context) {
+ lsmcontext_init(&scaff, context, contextlen, 0); /*scaffolding*/
+ security_release_secctx(&scaff);
+ }
#endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
kfree(acl);
if (tempfh) {
diff --git a/include/linux/security.h b/include/linux/security.h
index 07a239292e02..8bd4f28ef532 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -76,6 +76,39 @@ enum lsm_event {
LSM_POLICY_CHANGE,
};
+/*
+ * A "security context" is the text representation of
+ * the information used by LSMs.
+ * This structure contains the string, its length, and which LSM
+ * it is useful for.
+ */
+struct lsmcontext {
+ char *context; /* Provided by the module */
+ u32 len;
+ int slot; /* Identifies the module */
+};
+
+/**
+ * lsmcontext_init - initialize an lsmcontext structure.
+ * @cp: Pointer to the context to initialize
+ * @context: Initial context, or NULL
+ * @size: Size of context, or 0
+ * @slot: Which LSM provided the context
+ *
+ * Fill in the lsmcontext from the provided information.
+ */
+static inline void lsmcontext_init(struct lsmcontext *cp, char *context,
+ u32 size, int slot)
+{
+ cp->slot = slot;
+ cp->context = context;
+
+ if (context == NULL || size == 0)
+ cp->len = 0;
+ else
+ cp->len = strlen(context);
+}
+
/*
* Data exported by the security modules
*/
@@ -445,7 +478,7 @@ int security_ismaclabel(const char *name);
int security_secid_to_secctx(struct lsmblob *l, char **secdata, u32 *seclen);
int security_secctx_to_secid(const char *secdata, u32 seclen,
struct lsmblob *l);
-void security_release_secctx(char *secdata, u32 seclen);
+void security_release_secctx(struct lsmcontext *cp);
void security_inode_invalidate_secctx(struct inode *inode);
int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen);
@@ -1236,7 +1269,7 @@ static inline int security_secctx_to_secid(const char *secdata,
return -EOPNOTSUPP;
}
-static inline void security_release_secctx(char *secdata, u32 seclen)
+static inline void security_release_secctx(struct lsmcontext *cp)
{
}
diff --git a/include/net/scm.h b/include/net/scm.h
index bcb0f8560cdf..d3e0ac961a11 100644
--- a/include/net/scm.h
+++ b/include/net/scm.h
@@ -92,6 +92,7 @@ static __inline__ int scm_send(struct socket *sock, struct msghdr *msg,
#ifdef CONFIG_SECURITY_NETWORK
static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
{
+ struct lsmcontext context;
char *secdata;
u32 seclen;
int err;
@@ -101,7 +102,8 @@ static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct sc
if (!err) {
put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
- security_release_secctx(secdata, seclen);
+ lsmcontext_init(&context, secdata, seclen, 0);/*scaffolding*/
+ security_release_secctx(&context);
}
}
}
diff --git a/kernel/audit.c b/kernel/audit.c
index a52f8772477f..0467b2d284fa 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -1193,6 +1193,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
struct audit_sig_info *sig_data;
char *ctx = NULL;
u32 len;
+ struct lsmcontext scaff; /* scaffolding */
err = audit_netlink_ok(skb, msg_type);
if (err)
@@ -1437,15 +1438,18 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
}
sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL);
if (!sig_data) {
- if (lsmblob_is_set(&audit_sig_lsm))
- security_release_secctx(ctx, len);
+ if (lsmblob_is_set(&audit_sig_lsm)) {
+ lsmcontext_init(&scaff, ctx, len, 0);
+ security_release_secctx(&scaff);
+ }
return -ENOMEM;
}
sig_data->uid = from_kuid(&init_user_ns, audit_sig_uid);
sig_data->pid = audit_sig_pid;
if (lsmblob_is_set(&audit_sig_lsm)) {
memcpy(sig_data->ctx, ctx, len);
- security_release_secctx(ctx, len);
+ lsmcontext_init(&scaff, ctx, len, 0);
+ security_release_secctx(&scaff);
}
audit_send_reply(skb, seq, AUDIT_SIGNAL_INFO, 0, 0,
sig_data, sizeof(*sig_data) + len);
@@ -2074,6 +2078,7 @@ int audit_log_task_context(struct audit_buffer *ab)
unsigned len;
int error;
struct lsmblob le;
+ struct lsmcontext scaff; /* scaffolding */
security_task_getsecid(current, &le);
if (!lsmblob_is_set(&le))
@@ -2087,7 +2092,8 @@ int audit_log_task_context(struct audit_buffer *ab)
}
audit_log_format(ab, " subj=%s", ctx);
- security_release_secctx(ctx, len);
+ lsmcontext_init(&scaff, ctx, len, 0);
+ security_release_secctx(&scaff);
return 0;
error_path:
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index ebdd7eab9247..917e7550767a 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -942,6 +942,7 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
struct lsmblob *l, char *comm)
{
struct audit_buffer *ab;
+ struct lsmcontext lsmcxt;
char *ctx = NULL;
u32 len;
int rc = 0;
@@ -959,7 +960,8 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
rc = 1;
} else {
audit_log_format(ab, " obj=%s", ctx);
- security_release_secctx(ctx, len);
+ lsmcontext_init(&lsmcxt, ctx, len, 0); /*scaffolding*/
+ security_release_secctx(&lsmcxt);
}
}
audit_log_format(ab, " ocomm=");
@@ -1171,6 +1173,7 @@ static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name)
static void show_special(struct audit_context *context, int *call_panic)
{
+ struct lsmcontext lsmcxt;
struct audit_buffer *ab;
int i;
@@ -1203,7 +1206,8 @@ static void show_special(struct audit_context *context, int *call_panic)
*call_panic = 1;
} else {
audit_log_format(ab, " obj=%s", ctx);
- security_release_secctx(ctx, len);
+ lsmcontext_init(&lsmcxt, ctx, len, 0);
+ security_release_secctx(&lsmcxt);
}
}
if (context->ipc.has_perm) {
@@ -1350,6 +1354,7 @@ static void audit_log_name(struct audit_context *context, struct audit_names *n,
char *ctx = NULL;
u32 len;
struct lsmblob le;
+ struct lsmcontext lsmcxt;
lsmblob_init(&le, n->osid);
if (security_secid_to_secctx(&le, &ctx, &len)) {
@@ -1358,7 +1363,8 @@ static void audit_log_name(struct audit_context *context, struct audit_names *n,
*call_panic = 2;
} else {
audit_log_format(ab, " obj=%s", ctx);
- security_release_secctx(ctx, len);
+ lsmcontext_init(&lsmcxt, ctx, len, 0); /* scaffolding */
+ security_release_secctx(&lsmcxt);
}
}
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index e05f4ef68bd8..7834c357b60b 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -130,6 +130,7 @@ static void ip_cmsg_recv_checksum(struct msghdr *msg, struct sk_buff *skb,
static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
{
+ struct lsmcontext context;
struct lsmblob lb;
char *secdata;
u32 seclen;
@@ -144,7 +145,8 @@ static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
return;
put_cmsg(msg, SOL_IP, SCM_SECURITY, seclen, secdata);
- security_release_secctx(secdata, seclen);
+ lsmcontext_init(&context, secdata, seclen, 0); /* scaffolding */
+ security_release_secctx(&context);
}
static void ip_cmsg_recv_dstaddr(struct msghdr *msg, struct sk_buff *skb)
diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index 6098b586da07..93f308b5845d 100644
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -331,6 +331,7 @@ static int ctnetlink_dump_secctx(struct sk_buff *skb, const struct nf_conn *ct)
int len, ret;
char *secctx;
struct lsmblob le;
+ struct lsmcontext context;
lsmblob_init(&le, ct->secmark);
ret = security_secid_to_secctx(&le, &secctx, &len);
@@ -348,7 +349,8 @@ static int ctnetlink_dump_secctx(struct sk_buff *skb, const struct nf_conn *ct)
ret = 0;
nla_put_failure:
- security_release_secctx(secctx, len);
+ lsmcontext_init(&context, secctx, len, 0); /* scaffolding */
+ security_release_secctx(&context);
return ret;
}
#else
diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c
index 6e6fb1f9f6ba..0bde6a4426e3 100644
--- a/net/netfilter/nf_conntrack_standalone.c
+++ b/net/netfilter/nf_conntrack_standalone.c
@@ -176,6 +176,7 @@ static void ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
u32 len;
char *secctx;
struct lsmblob le;
+ struct lsmcontext context;
lsmblob_init(&le, ct->secmark);
ret = security_secid_to_secctx(&le, &secctx, &len);
@@ -184,7 +185,8 @@ static void ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
seq_printf(s, "secctx=%s ", secctx);
- security_release_secctx(secctx, len);
+ lsmcontext_init(&context, secctx, len, 0); /* scaffolding */
+ security_release_secctx(&context);
}
#else
static inline void ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
index 105018d19318..ba767bdd1a9a 100644
--- a/net/netfilter/nfnetlink_queue.c
+++ b/net/netfilter/nfnetlink_queue.c
@@ -399,6 +399,7 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
enum ip_conntrack_info uninitialized_var(ctinfo);
struct nfnl_ct_hook *nfnl_ct;
bool csum_verify;
+ struct lsmcontext scaff; /* scaffolding */
char *secdata = NULL;
u32 seclen = 0;
@@ -629,8 +630,10 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
}
nlh->nlmsg_len = skb->len;
- if (seclen)
- security_release_secctx(secdata, seclen);
+ if (seclen) {
+ lsmcontext_init(&scaff, secdata, seclen, 0);
+ security_release_secctx(&scaff);
+ }
return skb;
nla_put_failure:
@@ -638,8 +641,10 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
kfree_skb(skb);
net_err_ratelimited("nf_queue: error creating packet message\n");
nlmsg_failure:
- if (seclen)
- security_release_secctx(secdata, seclen);
+ if (seclen) {
+ lsmcontext_init(&scaff, secdata, seclen, 0);
+ security_release_secctx(&scaff);
+ }
return NULL;
}
diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c
index 57e0f81a2ec5..2f8c7415b6ff 100644
--- a/net/netlabel/netlabel_unlabeled.c
+++ b/net/netlabel/netlabel_unlabeled.c
@@ -387,6 +387,7 @@ int netlbl_unlhsh_add(struct net *net,
struct net_device *dev;
struct netlbl_unlhsh_iface *iface;
struct audit_buffer *audit_buf = NULL;
+ struct lsmcontext context;
char *secctx = NULL;
u32 secctx_len;
struct lsmblob le;
@@ -457,7 +458,9 @@ int netlbl_unlhsh_add(struct net *net,
&secctx,
&secctx_len) == 0) {
audit_log_format(audit_buf, " sec_obj=%s", secctx);
- security_release_secctx(secctx, secctx_len);
+ /* scaffolding */
+ lsmcontext_init(&context, secctx, secctx_len, 0);
+ security_release_secctx(&context);
}
audit_log_format(audit_buf, " res=%u", ret_val == 0 ? 1 : 0);
audit_log_end(audit_buf);
@@ -488,6 +491,7 @@ static int netlbl_unlhsh_remove_addr4(struct net *net,
struct netlbl_unlhsh_addr4 *entry;
struct audit_buffer *audit_buf;
struct net_device *dev;
+ struct lsmcontext context;
char *secctx;
u32 secctx_len;
struct lsmblob le;
@@ -516,7 +520,9 @@ static int netlbl_unlhsh_remove_addr4(struct net *net,
security_secid_to_secctx(&le,
&secctx, &secctx_len) == 0) {
audit_log_format(audit_buf, " sec_obj=%s", secctx);
- security_release_secctx(secctx, secctx_len);
+ /* scaffolding */
+ lsmcontext_init(&context, secctx, secctx_len, 0);
+ security_release_secctx(&context);
}
audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
audit_log_end(audit_buf);
@@ -553,6 +559,7 @@ static int netlbl_unlhsh_remove_addr6(struct net *net,
struct netlbl_unlhsh_addr6 *entry;
struct audit_buffer *audit_buf;
struct net_device *dev;
+ struct lsmcontext context;
char *secctx;
u32 secctx_len;
struct lsmblob le;
@@ -580,7 +587,8 @@ static int netlbl_unlhsh_remove_addr6(struct net *net,
security_secid_to_secctx(&le,
&secctx, &secctx_len) == 0) {
audit_log_format(audit_buf, " sec_obj=%s", secctx);
- security_release_secctx(secctx, secctx_len);
+ lsmcontext_init(&context, secctx, secctx_len, 0);
+ security_release_secctx(&context);
}
audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
audit_log_end(audit_buf);
@@ -1094,6 +1102,7 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd,
int ret_val = -ENOMEM;
struct netlbl_unlhsh_walk_arg *cb_arg = arg;
struct net_device *dev;
+ struct lsmcontext context;
void *data;
u32 secid;
char *secctx;
@@ -1161,7 +1170,9 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd,
NLBL_UNLABEL_A_SECCTX,
secctx_len,
secctx);
- security_release_secctx(secctx, secctx_len);
+ /* scaffolding */
+ lsmcontext_init(&context, secctx, secctx_len, 0);
+ security_release_secctx(&context);
if (ret_val != 0)
goto list_cb_failure;
diff --git a/net/netlabel/netlabel_user.c b/net/netlabel/netlabel_user.c
index 4145adf55a22..fba861c4ffbb 100644
--- a/net/netlabel/netlabel_user.c
+++ b/net/netlabel/netlabel_user.c
@@ -98,6 +98,7 @@ struct audit_buffer *netlbl_audit_start_common(int type,
struct netlbl_audit *audit_info)
{
struct audit_buffer *audit_buf;
+ struct lsmcontext context;
char *secctx;
u32 secctx_len;
struct lsmblob le;
@@ -117,7 +118,8 @@ struct audit_buffer *netlbl_audit_start_common(int type,
if (audit_info->secid != 0 &&
security_secid_to_secctx(&le, &secctx, &secctx_len) == 0) {
audit_log_format(audit_buf, " subj=%s", secctx);
- security_release_secctx(secctx, secctx_len);
+ lsmcontext_init(&context, secctx, secctx_len, 0);/*scaffolding*/
+ security_release_secctx(&context);
}
return audit_buf;
diff --git a/security/security.c b/security/security.c
index 9cfdc664239e..d25c099b46d1 100644
--- a/security/security.c
+++ b/security/security.c
@@ -458,6 +458,7 @@ void __init security_add_hooks(struct security_hook_list *hooks, int count,
&security_hook_heads.socket_getpeersec_dgram ||
hooks[i].head == &security_hook_heads.secctx_to_secid ||
hooks[i].head == &security_hook_heads.secid_to_secctx ||
+ hooks[i].head == &security_hook_heads.release_secctx ||
hooks[i].head == &security_hook_heads.ipc_getsecid ||
hooks[i].head == &security_hook_heads.task_getsecid ||
hooks[i].head == &security_hook_heads.inode_getsecid ||
@@ -2083,16 +2084,19 @@ int security_secctx_to_secid(const char *secdata, u32 seclen, struct lsmblob *l)
}
EXPORT_SYMBOL(security_secctx_to_secid);
-void security_release_secctx(char *secdata, u32 seclen)
+void security_release_secctx(struct lsmcontext *cp)
{
- int *display = current->security;
struct security_hook_list *hp;
hlist_for_each_entry(hp, &security_hook_heads.release_secctx, list)
- if (*display == LSMDATA_INVALID || *display == hp->slot) {
- hp->hook.release_secctx(secdata, seclen);
+ if (cp->slot == hp->slot) {
+ hp->hook.release_secctx(cp->context, cp->len);
+ lsmcontext_init(cp, NULL, 0, 0);
return;
}
+
+ pr_warn("%s context \"%s\" from slot %d not released\n", __func__,
+ cp->context, cp->slot);
}
EXPORT_SYMBOL(security_release_secctx);
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index e9560b078efe..3834b751d1e9 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -4439,11 +4439,16 @@ static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
return 0;
}
-/*
- * There used to be a smack_release_secctx hook
- * that did nothing back when hooks were in a vector.
- * Now that there's a list such a hook adds cost.
+/**
+ * smack_release_secctx - do everything necessary to free a context
+ * @secdata: Unused
+ * @seclen: Unused
+ *
+ * Do nothing but hold a slot in the hooks list.
*/
+static void smack_release_secctx(char *secdata, u32 seclen)
+{
+}
static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
{
@@ -4683,6 +4688,7 @@ static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(ismaclabel, smack_ismaclabel),
LSM_HOOK_INIT(secid_to_secctx, smack_secid_to_secctx),
LSM_HOOK_INIT(secctx_to_secid, smack_secctx_to_secid),
+ LSM_HOOK_INIT(release_secctx, smack_release_secctx),
LSM_HOOK_INIT(inode_notifysecctx, smack_inode_notifysecctx),
LSM_HOOK_INIT(inode_setsecctx, smack_inode_setsecctx),
LSM_HOOK_INIT(inode_getsecctx, smack_inode_getsecctx),
--
2.20.1
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