--- v1
+++ v24
@@ -1,131 +1,292 @@
-Convert the secid_to_secctx hooks to use the lsm_export
-structure instead of a u32 secid. There is some scaffolding
-involved that will be removed when security_secid_to_secctx()
-is updated.
+Change the security_cred_getsecid() interface to fill in a
+lsmblob instead of a u32 secid. The associated data elements
+in the audit sub-system are changed from a secid to a lsmblob
+to accommodate multiple possible LSM audit users.
+Reviewed-by: Kees Cook <keescook@chromium.org>
+Reviewed-by: John Johansen <john.johansen@canonical.com>
+Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
+Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
+Cc: linux-integrity@vger.kernel.org
+Cc: linux-audit@redhat.com
---
- include/linux/lsm_hooks.h | 5 +++--
- security/apparmor/include/secid.h | 2 +-
- security/apparmor/secid.c | 6 ++----
- security/security.c | 5 ++++-
- security/selinux/hooks.c | 6 +++++-
- security/smack/smack_lsm.c | 9 +++++++--
- 6 files changed, 22 insertions(+), 11 deletions(-)
+ include/linux/security.h | 2 +-
+ kernel/audit.c | 25 +++++++----------------
+ kernel/audit.h | 3 ++-
+ kernel/auditsc.c | 33 +++++++++++--------------------
+ security/integrity/ima/ima_main.c | 8 ++++----
+ security/security.c | 12 ++++++++---
+ 6 files changed, 35 insertions(+), 48 deletions(-)
-diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
-index 690ab020508e..11ace5c923bd 100644
---- a/include/linux/lsm_hooks.h
-+++ b/include/linux/lsm_hooks.h
-@@ -1322,7 +1322,7 @@
- * This does mean that the length could change between calls to check the
- * length and the next call which actually allocates and returns the
- * secdata.
-- * @secid contains the security ID.
-+ * @l points to the security information.
- * @secdata contains the pointer that stores the converted security
- * context.
- * @seclen pointer which contains the length of the data
-@@ -1672,7 +1672,8 @@ union security_list_options {
- int (*getprocattr)(struct task_struct *p, char *name, char **value);
- int (*setprocattr)(const char *name, void *value, size_t size);
- int (*ismaclabel)(const char *name);
-- int (*secid_to_secctx)(u32 secid, char **secdata, u32 *seclen);
-+ int (*secid_to_secctx)(struct lsm_export *l, char **secdata,
-+ u32 *seclen);
- int (*secctx_to_secid)(const char *secdata, u32 seclen, u32 *secid);
- void (*release_secctx)(char *secdata, u32 seclen);
-
-diff --git a/security/apparmor/include/secid.h b/security/apparmor/include/secid.h
-index c283c620efe3..03369183f512 100644
---- a/security/apparmor/include/secid.h
-+++ b/security/apparmor/include/secid.h
-@@ -26,7 +26,7 @@ struct aa_label;
- #define AA_SECID_WILDCARD 1
-
- struct aa_label *aa_secid_to_label(struct lsm_export *l);
--int apparmor_secid_to_secctx(u32 secid, char **secdata, u32 *seclen);
-+int apparmor_secid_to_secctx(struct lsm_export *l, char **secdata, u32 *seclen);
- int apparmor_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid);
- void apparmor_release_secctx(char *secdata, u32 seclen);
-
-diff --git a/security/apparmor/secid.c b/security/apparmor/secid.c
-index 1546c45a2a18..ab4dc165e43e 100644
---- a/security/apparmor/secid.c
-+++ b/security/apparmor/secid.c
-@@ -81,15 +81,13 @@ static inline void aa_import_secid(struct lsm_export *l, u32 secid)
- l->apparmor = secid;
- }
-
--int apparmor_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
-+int apparmor_secid_to_secctx(struct lsm_export *l, char **secdata, u32 *seclen)
- {
- /* TODO: cache secctx and ref count so we don't have to recreate */
-- struct lsm_export data;
- struct aa_label *label;
- int len;
-
-- aa_import_secid(&data, secid);
-- label = aa_secid_to_label(&data);
-+ label = aa_secid_to_label(l);
-
- AA_BUG(!seclen);
-
+diff --git a/include/linux/security.h b/include/linux/security.h
+index e8d73b0220e4..e4a4816f1b94 100644
+--- a/include/linux/security.h
++++ b/include/linux/security.h
+@@ -468,7 +468,7 @@ int security_cred_alloc_blank(struct cred *cred, gfp_t gfp);
+ void security_cred_free(struct cred *cred);
+ int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp);
+ void security_transfer_creds(struct cred *new, const struct cred *old);
+-void security_cred_getsecid(const struct cred *c, u32 *secid);
++void security_cred_getsecid(const struct cred *c, struct lsmblob *blob);
+ int security_kernel_act_as(struct cred *new, struct lsmblob *blob);
+ int security_kernel_create_files_as(struct cred *new, struct inode *inode);
+ int security_kernel_module_request(char *kmod_name);
+diff --git a/kernel/audit.c b/kernel/audit.c
+index e70bbd6b91c4..f6af7b27a6fa 100644
+--- a/kernel/audit.c
++++ b/kernel/audit.c
+@@ -125,7 +125,7 @@ static u32 audit_backlog_wait_time = AUDIT_BACKLOG_WAIT_TIME;
+ /* The identity of the user shutting down the audit system. */
+ static kuid_t audit_sig_uid = INVALID_UID;
+ static pid_t audit_sig_pid = -1;
+-static u32 audit_sig_sid;
++struct lsmblob audit_sig_lsm;
+
+ /* Records can be lost in several ways:
+ 0) [suppressed in audit_alloc]
+@@ -1441,29 +1441,21 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+ }
+ case AUDIT_SIGNAL_INFO:
+ len = 0;
+- if (audit_sig_sid) {
+- struct lsmblob blob;
+-
+- /*
+- * lsmblob_init sets all values in the lsmblob
+- * to audit_sig_sid. This is temporary until
+- * audit_sig_sid is converted to a lsmblob, which
+- * happens later in this patch set.
+- */
+- lsmblob_init(&blob, audit_sig_sid);
+- err = security_secid_to_secctx(&blob, &ctx, &len);
++ if (lsmblob_is_set(&audit_sig_lsm)) {
++ err = security_secid_to_secctx(&audit_sig_lsm, &ctx,
++ &len);
+ if (err)
+ return err;
+ }
+ sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL);
+ if (!sig_data) {
+- if (audit_sig_sid)
++ if (lsmblob_is_set(&audit_sig_lsm))
+ security_release_secctx(ctx, len);
+ return -ENOMEM;
+ }
+ sig_data->uid = from_kuid(&init_user_ns, audit_sig_uid);
+ sig_data->pid = audit_sig_pid;
+- if (audit_sig_sid) {
++ if (lsmblob_is_set(&audit_sig_lsm)) {
+ memcpy(sig_data->ctx, ctx, len);
+ security_release_secctx(ctx, len);
+ }
+@@ -2352,7 +2344,6 @@ int audit_set_loginuid(kuid_t loginuid)
+ int audit_signal_info(int sig, struct task_struct *t)
+ {
+ kuid_t uid = current_uid(), auid;
+- struct lsmblob blob;
+
+ if (auditd_test_task(t) &&
+ (sig == SIGTERM || sig == SIGHUP ||
+@@ -2363,9 +2354,7 @@ int audit_signal_info(int sig, struct task_struct *t)
+ audit_sig_uid = auid;
+ else
+ audit_sig_uid = uid;
+- security_task_getsecid(current, &blob);
+- /* scaffolding until audit_sig_sid is converted */
+- audit_sig_sid = blob.secid[0];
++ security_task_getsecid(current, &audit_sig_lsm);
+ }
+
+ return audit_signal_info_syscall(t);
+diff --git a/kernel/audit.h b/kernel/audit.h
+index 3b9c0945225a..ce41886807bb 100644
+--- a/kernel/audit.h
++++ b/kernel/audit.h
+@@ -9,6 +9,7 @@
+ #include <linux/fs.h>
+ #include <linux/audit.h>
+ #include <linux/skbuff.h>
++#include <linux/security.h>
+ #include <uapi/linux/mqueue.h>
+ #include <linux/tty.h>
+
+@@ -134,7 +135,7 @@ struct audit_context {
+ kuid_t target_auid;
+ kuid_t target_uid;
+ unsigned int target_sessionid;
+- u32 target_sid;
++ struct lsmblob target_lsm;
+ char target_comm[TASK_COMM_LEN];
+
+ struct audit_tree_refs *trees, *first_trees;
+diff --git a/kernel/auditsc.c b/kernel/auditsc.c
+index 7883b8ac8ea4..c766502b58f2 100644
+--- a/kernel/auditsc.c
++++ b/kernel/auditsc.c
+@@ -111,7 +111,7 @@ struct audit_aux_data_pids {
+ kuid_t target_auid[AUDIT_AUX_PIDS];
+ kuid_t target_uid[AUDIT_AUX_PIDS];
+ unsigned int target_sessionid[AUDIT_AUX_PIDS];
+- u32 target_sid[AUDIT_AUX_PIDS];
++ struct lsmblob target_lsm[AUDIT_AUX_PIDS];
+ char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
+ int pid_count;
+ };
+@@ -993,14 +993,14 @@ static inline void audit_free_context(struct audit_context *context)
+ }
+
+ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
+- kuid_t auid, kuid_t uid, unsigned int sessionid,
+- u32 sid, char *comm)
++ kuid_t auid, kuid_t uid,
++ unsigned int sessionid,
++ struct lsmblob *blob, char *comm)
+ {
+ struct audit_buffer *ab;
+ char *ctx = NULL;
+ u32 len;
+ int rc = 0;
+- struct lsmblob blob;
+
+ ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
+ if (!ab)
+@@ -1009,9 +1009,8 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
+ audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid,
+ from_kuid(&init_user_ns, auid),
+ from_kuid(&init_user_ns, uid), sessionid);
+- if (sid) {
+- lsmblob_init(&blob, sid);
+- if (security_secid_to_secctx(&blob, &ctx, &len)) {
++ if (lsmblob_is_set(blob)) {
++ if (security_secid_to_secctx(blob, &ctx, &len)) {
+ audit_log_format(ab, " obj=(none)");
+ rc = 1;
+ } else {
+@@ -1582,7 +1581,7 @@ static void audit_log_exit(void)
+ axs->target_auid[i],
+ axs->target_uid[i],
+ axs->target_sessionid[i],
+- axs->target_sid[i],
++ &axs->target_lsm[i],
+ axs->target_comm[i]))
+ call_panic = 1;
+ }
+@@ -1591,7 +1590,7 @@ static void audit_log_exit(void)
+ audit_log_pid_context(context, context->target_pid,
+ context->target_auid, context->target_uid,
+ context->target_sessionid,
+- context->target_sid, context->target_comm))
++ &context->target_lsm, context->target_comm))
+ call_panic = 1;
+
+ if (context->pwd.dentry && context->pwd.mnt) {
+@@ -1769,7 +1768,7 @@ void __audit_syscall_exit(int success, long return_code)
+ context->aux = NULL;
+ context->aux_pids = NULL;
+ context->target_pid = 0;
+- context->target_sid = 0;
++ lsmblob_init(&context->target_lsm, 0);
+ context->sockaddr_len = 0;
+ context->type = 0;
+ context->fds[0] = -1;
+@@ -2421,15 +2420,12 @@ int __audit_sockaddr(int len, void *a)
+ void __audit_ptrace(struct task_struct *t)
+ {
+ struct audit_context *context = audit_context();
+- struct lsmblob blob;
+
+ context->target_pid = task_tgid_nr(t);
+ context->target_auid = audit_get_loginuid(t);
+ context->target_uid = task_uid(t);
+ context->target_sessionid = audit_get_sessionid(t);
+- security_task_getsecid(t, &blob);
+- /* scaffolding - until target_sid is converted */
+- context->target_sid = blob.secid[0];
++ security_task_getsecid(t, &context->target_lsm);
+ memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
+ }
+
+@@ -2445,7 +2441,6 @@ int audit_signal_info_syscall(struct task_struct *t)
+ struct audit_aux_data_pids *axp;
+ struct audit_context *ctx = audit_context();
+ kuid_t t_uid = task_uid(t);
+- struct lsmblob blob;
+
+ if (!audit_signals || audit_dummy_context())
+ return 0;
+@@ -2457,9 +2452,7 @@ int audit_signal_info_syscall(struct task_struct *t)
+ ctx->target_auid = audit_get_loginuid(t);
+ ctx->target_uid = t_uid;
+ ctx->target_sessionid = audit_get_sessionid(t);
+- security_task_getsecid(t, &blob);
+- /* scaffolding until target_sid is converted */
+- ctx->target_sid = blob.secid[0];
++ security_task_getsecid(t, &ctx->target_lsm);
+ memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
+ return 0;
+ }
+@@ -2480,9 +2473,7 @@ int audit_signal_info_syscall(struct task_struct *t)
+ axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
+ axp->target_uid[axp->pid_count] = t_uid;
+ axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
+- security_task_getsecid(t, &blob);
+- /* scaffolding until target_sid is converted */
+- axp->target_sid[axp->pid_count] = blob.secid[0];
++ security_task_getsecid(t, &axp->target_lsm[axp->pid_count]);
+ memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
+ axp->pid_count++;
+
+diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
+index 175a79076569..e4ed01b1919a 100644
+--- a/security/integrity/ima/ima_main.c
++++ b/security/integrity/ima/ima_main.c
+@@ -469,7 +469,6 @@ int ima_file_mprotect(struct vm_area_struct *vma, unsigned long prot)
+ int ima_bprm_check(struct linux_binprm *bprm)
+ {
+ int ret;
+- u32 secid;
+ struct lsmblob blob;
+
+ security_task_getsecid(current, &blob);
+@@ -479,9 +478,10 @@ int ima_bprm_check(struct linux_binprm *bprm)
+ if (ret)
+ return ret;
+
+- security_cred_getsecid(bprm->cred, &secid);
+- return process_measurement(bprm->file, bprm->cred, secid, NULL, 0,
+- MAY_EXEC, CREDS_CHECK);
++ security_cred_getsecid(bprm->cred, &blob);
++ /* scaffolding until process_measurement changes */
++ return process_measurement(bprm->file, bprm->cred, blob.secid[0],
++ NULL, 0, MAY_EXEC, CREDS_CHECK);
+ }
+
+ /**
diff --git a/security/security.c b/security/security.c
-index 60dd064c0531..adf4cb768665 100644
+index 9241245a9d4b..45824239cb2f 100644
--- a/security/security.c
+++ b/security/security.c
-@@ -2002,7 +2002,10 @@ EXPORT_SYMBOL(security_ismaclabel);
-
- int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
- {
-- return call_int_hook(secid_to_secctx, -EOPNOTSUPP, secid, secdata,
-+ struct lsm_export data;
+@@ -1739,10 +1739,16 @@ void security_transfer_creds(struct cred *new, const struct cred *old)
+ call_void_hook(cred_transfer, new, old);
+ }
+
+-void security_cred_getsecid(const struct cred *c, u32 *secid)
++void security_cred_getsecid(const struct cred *c, struct lsmblob *blob)
+ {
+- *secid = 0;
+- call_void_hook(cred_getsecid, c, secid);
++ struct security_hook_list *hp;
+
-+ lsm_export_to_all(&data, secid);
-+ return call_int_hook(secid_to_secctx, -EOPNOTSUPP, &data, secdata,
- seclen);
- }
- EXPORT_SYMBOL(security_secid_to_secctx);
-diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
-index bfd0f1f5979f..16d902158e8a 100644
---- a/security/selinux/hooks.c
-+++ b/security/selinux/hooks.c
-@@ -6301,8 +6301,12 @@ static int selinux_ismaclabel(const char *name)
- return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
- }
-
--static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
-+static int selinux_secid_to_secctx(struct lsm_export *l, char **secdata,
-+ u32 *seclen)
- {
-+ u32 secid;
-+
-+ selinux_import_secid(l, &secid);
- return security_sid_to_context(&selinux_state, secid,
- secdata, seclen);
- }
-diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
-index a3776501965d..809af981f14c 100644
---- a/security/smack/smack_lsm.c
-+++ b/security/smack/smack_lsm.c
-@@ -4433,9 +4433,14 @@ static int smack_ismaclabel(const char *name)
- *
- * Exists for networking code.
- */
--static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
-+static int smack_secid_to_secctx(struct lsm_export *l, char **secdata,
-+ u32 *seclen)
- {
-- struct smack_known *skp = smack_from_secid(secid);
-+ struct smack_known *skp;
-+ u32 secid;
-+
-+ smack_import_secid(l, &secid);
-+ skp = smack_from_secid(secid);
-
- if (secdata)
- *secdata = skp->smk_known;
++ lsmblob_init(blob, 0);
++ hlist_for_each_entry(hp, &security_hook_heads.cred_getsecid, list) {
++ if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
++ continue;
++ hp->hook.cred_getsecid(c, &blob->secid[hp->lsmid->slot]);
++ }
+ }
+ EXPORT_SYMBOL(security_cred_getsecid);
+
--
-2.19.1
+2.25.4