1 files changed, 92 insertions, 0 deletions
diff --git a/usr/src/uts/common/os/upanic.c b/usr/src/uts/common/os/upanic.c
new file mode 100644
index 0000000000..8acb9440f2
--- /dev/null
+++ b/usr/src/uts/common/os/upanic.c
@@ -0,0 +1,92 @@
+/*
+ * This file and its contents are supplied under the terms of the
+ * Common Development and Distribution License ("CDDL"), version 1.0.
+ * You may only use this file in accordance with the terms of version
+ * 1.0 of the CDDL.
+ *
+ * A full copy of the text of the CDDL should have accompanied this
+ * source.  A copy of the CDDL is also available via the Internet at
+ * http://www.illumos.org/license/CDDL.
+ */
+
+/*
+ * Copyright 2020 Oxide Computer Company
+ */
+
+#include <sys/proc.h>
+#include <c2/audit.h>
+#include <sys/procfs.h>
+#include <sys/core.h>
+
+/*
+ * This function is meant to be a guaranteed abort that generates a core file
+ * that allows up to 1k of data to enter into an elfnote in the process. This is
+ * meant to insure that even in the face of other problems, this can get out.
+ */
+
+void
+upanic(void *addr, size_t len)
+{
+	kthread_t *t = curthread;
+	proc_t *p = curproc;
+	klwp_t *lwp = ttolwp(t);
+	uint32_t auditing = AU_AUDITING();
+	uint32_t upflag = P_UPF_PANICKED;
+	void *buf;
+	int code;
+
+	/*
+	 * Before we worry about the data that the user has as a message, go
+	 * ahead and make sure we try and get all the other threads stopped.
+	 * That'll help us make sure that nothing else is going on and we don't
+	 * lose a race.
+	 */
+	mutex_enter(&p->p_lock);
+	lwp->lwp_cursig = SIGABRT;
+	mutex_exit(&p->p_lock);
+
+	proc_is_exiting(p);
+	if (exitlwps(1) != 0) {
+		mutex_enter(&p->p_lock);
+		lwp_exit();
+	}
+
+	/*
+	 * Copy in the user data. We truncate it to PRUPANIC_BUFLEN no matter
+	 * what and ensure that the last data was set to zero.
+	 */
+	if (addr != NULL && len > 0) {
+		size_t copylen;
+
+		upflag |= P_UPF_HAVEMSG;
+
+		if (len >= PRUPANIC_BUFLEN) {
+			copylen = PRUPANIC_BUFLEN;
+			upflag |= P_UPF_TRUNCMSG;
+		} else {
+			copylen = len;
+		}
+
+		buf = kmem_zalloc(PRUPANIC_BUFLEN, KM_SLEEP);
+		if (copyin(addr, buf, copylen) != 0) {
+			upflag |= P_UPF_INVALMSG;
+			upflag &= ~P_UPF_HAVEMSG;
+		} else {
+			mutex_enter(&p->p_lock);
+			ASSERT3P(p->p_upanic, ==, NULL);
+			p->p_upanic = buf;
+			mutex_exit(&p->p_lock);
+		}
+	}
+
+	mutex_enter(&p->p_lock);
+	p->p_upanicflag = upflag;
+	mutex_exit(&p->p_lock);
+
+	if (auditing)		/* audit core dump */
+		audit_core_start(SIGABRT);
+	code = core(SIGABRT, B_FALSE);
+	if (auditing)		/* audit core dump */
+		audit_core_finish(code ? CLD_KILLED : CLD_DUMPED);
+	exit(code ? CLD_KILLED : CLD_DUMPED, SIGABRT);
+}