On Mon, Apr 06, 2020 at 05:01:57PM -0700, Casey Schaufler wrote: > Create a new audit record type to contain the object information > when there are multiple security modules that require such data. > This record is emitted before the other records for the event, but > is linked with the same timestamp and serial number. > > Signed-off-by: Casey Schaufler <[email protected]>
Reviewed-by: Kees Cook <[email protected]> -Kees > --- > include/linux/audit.h | 2 ++ > include/uapi/linux/audit.h | 1 + > kernel/audit.c | 53 +++++++++++++++++++++++++++++ > kernel/audit.h | 4 +-- > kernel/auditsc.c | 70 +++++--------------------------------- > 5 files changed, 67 insertions(+), 63 deletions(-) > > diff --git a/include/linux/audit.h b/include/linux/audit.h > index 8e1c759fd1ff..4c7c0ee867a1 100644 > --- a/include/linux/audit.h > +++ b/include/linux/audit.h > @@ -163,6 +163,8 @@ extern void audit_log_path_denied(int > type, > extern void audit_log_lost(const char *message); > > extern int audit_log_task_context(struct audit_buffer *ab); > +extern int audit_log_object_context(struct audit_buffer *ab, > + struct lsmblob *blob); > extern void audit_log_task_info(struct audit_buffer *ab); > > extern int audit_update_lsm_rules(void); > diff --git a/include/uapi/linux/audit.h b/include/uapi/linux/audit.h > index 2e6dbf907ee3..2269100ba0ca 100644 > --- a/include/uapi/linux/audit.h > +++ b/include/uapi/linux/audit.h > @@ -139,6 +139,7 @@ > #define AUDIT_MAC_CALIPSO_ADD 1418 /* NetLabel: add CALIPSO DOI > entry */ > #define AUDIT_MAC_CALIPSO_DEL 1419 /* NetLabel: del CALIPSO DOI > entry */ > #define AUDIT_MAC_TASK_CONTEXTS 1420 /* Multiple LSM contexts */ > +#define AUDIT_MAC_OBJ_CONTEXTS 1421 /* Multiple LSM object contexts > */ > > #define AUDIT_FIRST_KERN_ANOM_MSG 1700 > #define AUDIT_LAST_KERN_ANOM_MSG 1799 > diff --git a/kernel/audit.c b/kernel/audit.c > index 00a4fbecfdf7..6a6146a34cc9 100644 > --- a/kernel/audit.c > +++ b/kernel/audit.c > @@ -2113,6 +2113,59 @@ int audit_log_task_context(struct audit_buffer *ab) > } > EXPORT_SYMBOL(audit_log_task_context); > > +int audit_log_object_context(struct audit_buffer *ab, > + struct lsmblob *blob) > +{ > + int i; > + int error; > + bool sep = false; > + struct lsmcontext lsmdata; > + struct audit_buffer *lsmab = NULL; > + struct audit_context *context = NULL; > + > + /* > + * If there is more than one security module that has a > + * object "context" it's necessary to put the object data > + * into a separate record to maintain compatibility. > + */ > + if (security_lsm_slot_name(1) != NULL) { > + audit_log_format(ab, " obj=?"); > + context = ab->ctx; > + if (context) > + lsmab = audit_log_start(context, GFP_KERNEL, > + AUDIT_MAC_OBJ_CONTEXTS); > + } > + > + for (i = 0; i < LSMBLOB_ENTRIES; i++) { > + if (blob->secid[i] == 0) > + continue; > + error = security_secid_to_secctx(blob, &lsmdata, i); > + if (error && error != -EINVAL) { > + audit_panic("error in audit_log_object_context"); > + return error; > + } > + > + if (context) { > + audit_log_format(lsmab, "%sobj_%s=%s", > + sep ? " " : "", > + security_lsm_slot_name(i), > + lsmdata.context); > + sep = true; > + } else > + audit_log_format(ab, " obj=%s", lsmdata.context); > + > + security_release_secctx(&lsmdata); > + if (!context) > + break; > + } > + > + if (context) > + audit_log_end(lsmab); > + > + return 0; > +} > +EXPORT_SYMBOL(audit_log_object_context); > + > void audit_log_d_path_exe(struct audit_buffer *ab, > struct mm_struct *mm) > { > diff --git a/kernel/audit.h b/kernel/audit.h > index f65f516913c6..9a26ba213f6a 100644 > --- a/kernel/audit.h > +++ b/kernel/audit.h > @@ -78,7 +78,7 @@ struct audit_names { > kuid_t uid; > kgid_t gid; > dev_t rdev; > - u32 osid; > + struct lsmblob oblob; > struct audit_cap_data fcap; > unsigned int fcap_ver; > unsigned char type; /* record type */ > @@ -152,7 +152,7 @@ struct audit_context { > kuid_t uid; > kgid_t gid; > umode_t mode; > - u32 osid; > + struct lsmblob oblob; > int has_perm; > uid_t perm_uid; > gid_t perm_gid; > diff --git a/kernel/auditsc.c b/kernel/auditsc.c > index 4df540c32581..f567f3776ca5 100644 > --- a/kernel/auditsc.c > +++ b/kernel/auditsc.c > @@ -659,14 +659,6 @@ static int audit_filter_rules(struct task_struct *tsk, > if (f->lsm_isset) { > /* Find files that match */ > if (name) { > - /* > - * lsmblob_init sets all values in the > - * lsmblob to sid. This is temporary > - * until name->osid is converted to a > - * lsmblob, which happens later in > - * this patch set. > - */ > - lsmblob_init(&blob, name->osid); > result = security_audit_rule_match( > &blob, > f->type, > @@ -674,7 +666,6 @@ static int audit_filter_rules(struct task_struct *tsk, > f->lsm_rules); > } else if (ctx) { > list_for_each_entry(n, > &ctx->names_list, list) { > - lsmblob_init(&blob, name->osid); > if (security_audit_rule_match( > &blob, > f->type, > @@ -688,8 +679,7 @@ static int audit_filter_rules(struct task_struct *tsk, > /* Find ipc objects that match */ > if (!ctx || ctx->type != AUDIT_IPC) > break; > - lsmblob_init(&blob, ctx->ipc.osid); > - if (security_audit_rule_match(&blob, > + if (security_audit_rule_match(&ctx->ipc.oblob, > f->type, f->op, > f->lsm_rules)) > ++result; > @@ -969,7 +959,6 @@ static int audit_log_pid_context(struct audit_context > *context, pid_t pid, > struct lsmblob *blob, char *comm) > { > struct audit_buffer *ab; > - struct lsmcontext lsmctx; > int rc = 0; > > ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID); > @@ -979,15 +968,7 @@ 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 (lsmblob_is_set(blob)) { > - if (security_secid_to_secctx(blob, &lsmctx, LSMBLOB_FIRST)) { > - audit_log_format(ab, " obj=(none)"); > - rc = 1; > - } else { > - audit_log_format(ab, " obj=%s", lsmctx.context); > - security_release_secctx(&lsmctx); > - } > - } > + rc = audit_log_object_context(ab, blob); > audit_log_format(ab, " ocomm="); > audit_log_untrustedstring(ab, comm); > audit_log_end(ab); > @@ -1214,26 +1195,14 @@ static void show_special(struct audit_context > *context, int *call_panic) > context->socketcall.args[i]); > break; } > case AUDIT_IPC: { > - u32 osid = context->ipc.osid; > + struct lsmblob *oblob = &context->ipc.oblob; > > audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho", > from_kuid(&init_user_ns, context->ipc.uid), > from_kgid(&init_user_ns, context->ipc.gid), > context->ipc.mode); > - if (osid) { > - struct lsmcontext lsmcxt; > - struct lsmblob blob; > - > - lsmblob_init(&blob, osid); > - if (security_secid_to_secctx(&blob, &lsmcxt, > - LSMBLOB_FIRST)) { > - audit_log_format(ab, " osid=%u", osid); > - *call_panic = 1; > - } else { > - audit_log_format(ab, " obj=%s", lsmcxt.context); > - security_release_secctx(&lsmcxt); > - } > - } > + if (audit_log_object_context(ab, oblob)) > + *call_panic = 1; > if (context->ipc.has_perm) { > audit_log_end(ab); > ab = audit_log_start(context, GFP_KERNEL, > @@ -1373,20 +1342,8 @@ static void audit_log_name(struct audit_context > *context, struct audit_names *n, > from_kgid(&init_user_ns, n->gid), > MAJOR(n->rdev), > MINOR(n->rdev)); > - if (n->osid != 0) { > - struct lsmblob blob; > - struct lsmcontext lsmctx; > - > - lsmblob_init(&blob, n->osid); > - if (security_secid_to_secctx(&blob, &lsmctx, LSMBLOB_FIRST)) { > - audit_log_format(ab, " osid=%u", n->osid); > - if (call_panic) > - *call_panic = 2; > - } else { > - audit_log_format(ab, " obj=%s", lsmctx.context); > - security_release_secctx(&lsmctx); > - } > - } > + if (audit_log_object_context(ab, &n->oblob) && call_panic) > + *call_panic = 2; > > /* log the audit_names record type */ > switch (n->type) { > @@ -1935,17 +1892,13 @@ static void audit_copy_inode(struct audit_names *name, > const struct dentry *dentry, > struct inode *inode, unsigned int flags) > { > - struct lsmblob blob; > - > name->ino = inode->i_ino; > name->dev = inode->i_sb->s_dev; > name->mode = inode->i_mode; > name->uid = inode->i_uid; > name->gid = inode->i_gid; > name->rdev = inode->i_rdev; > - security_inode_getsecid(inode, &blob); > - /* scaffolding until osid is updated */ > - name->osid = blob.secid[0]; > + security_inode_getsecid(inode, &name->oblob); > if (flags & AUDIT_INODE_NOEVAL) { > name->fcap_ver = -1; > return; > @@ -2291,16 +2244,11 @@ void __audit_mq_getsetattr(mqd_t mqdes, struct > mq_attr *mqstat) > void __audit_ipc_obj(struct kern_ipc_perm *ipcp) > { > struct audit_context *context = audit_context(); > - struct lsmblob blob; > context->ipc.uid = ipcp->uid; > context->ipc.gid = ipcp->gid; > context->ipc.mode = ipcp->mode; > context->ipc.has_perm = 0; > - security_ipc_getsecid(ipcp, &blob); > - /* context->ipc.osid will be changed to a lsmblob later in > - * the patch series. This will allow auditing of all the object > - * labels associated with the ipc object. */ > - context->ipc.osid = lsmblob_value(&blob); > + security_ipc_getsecid(ipcp, &context->ipc.oblob); > context->type = AUDIT_IPC; > } > > -- > 2.24.1 > -- Kees Cook -- Linux-audit mailing list [email protected] https://www.redhat.com/mailman/listinfo/linux-audit
