git: 4819e5aeda4e - main - Add new privilege PRIV_KDB_SET_BACKEND

The branch main has been updated by stevek:

URL: https://cgit.FreeBSD.org/src/commit/?id=4819e5aeda4ef1a193a08e29b4099c3c30369a81

commit 4819e5aeda4ef1a193a08e29b4099c3c30369a81
Author:     Stephen J. Kiernan <stevek@FreeBSD.org>
AuthorDate: 2023-04-16 03:59:52 +0000
Commit:     Stephen J. Kiernan <stevek@FreeBSD.org>
CommitDate: 2023-04-16 18:37:58 +0000

    Add new privilege PRIV_KDB_SET_BACKEND
    
    Summary:
    Check for PRIV_KDB_SET_BACKEND before allowing a thread to change
    the KDB backend.
    
    Obtained from:  Juniper Networks, Inc.
    Reviewers: sjg, emaste
    Subscribers: imp
    
    Differential Revision: https://reviews.freebsd.org/D39538
---
 sys/kern/subr_kdb.c | 6 ++++++
 sys/sys/priv.h      | 7 ++++++-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/sys/kern/subr_kdb.c b/sys/kern/subr_kdb.c
index ff981cdfe47c..8aae19b728c8 100644
--- a/sys/kern/subr_kdb.c
+++ b/sys/kern/subr_kdb.c
@@ -40,6 +40,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/malloc.h>
 #include <sys/lock.h>
 #include <sys/pcpu.h>
+#include <sys/priv.h>
 #include <sys/proc.h>
 #include <sys/sbuf.h>
 #include <sys/smp.h>
@@ -484,6 +485,11 @@ int
 kdb_dbbe_select(const char *name)
 {
 	struct kdb_dbbe *be, **iter;
+	int error;
+
+	error = priv_check(curthread, PRIV_KDB_SET_BACKEND);
+	if (error)
+		return (error);
 
 	SET_FOREACH(iter, kdb_dbbe_set) {
 		be = *iter;
diff --git a/sys/sys/priv.h b/sys/sys/priv.h
index 20bfc7312ce3..cb4dcecea4aa 100644
--- a/sys/sys/priv.h
+++ b/sys/sys/priv.h
@@ -515,10 +515,15 @@
 #define	PRIV_KMEM_READ		680	/* Open mem/kmem for reading. */
 #define	PRIV_KMEM_WRITE		681	/* Open mem/kmem for writing. */
 
+/*
+ * Kernel debugger privileges.
+ */
+#define	PRIV_KDB_SET_BACKEND	690	/* Allow setting KDB backend. */
+
 /*
  * Track end of privilege list.
  */
-#define	_PRIV_HIGHEST		682
+#define	_PRIV_HIGHEST		691
 
 /*
  * Validate that a named privilege is known by the privilege system.  Invalid