Module Name: src
Committed By: rin
Date: Wed Sep 22 05:42:19 UTC 2021
Modified Files:
src/sys/kern: kern_ksyms.c
Log Message:
ksymsmmap: Add missing uao_reference(9) call for ks->ks_uobj.
Fix failure for savecore(8) and subsequent kernel panic, introduced to
kern_ksyms.c rev 1.03, at least for sh3 and alpha.
For sh3 and alpha, savecore(8) supports coff and ecoff, respectively, via
libkvm via nlist(3). nlist(3) routines for coff and ecoff use mmap(2) and
munmap(2) for /dev/ksyms.
This munmap(2) decrements reference count for ks->ks_uobj. Unless it is
incremented in ksymsmmap(), ks->ks_uobj will be freed unexpectedly.
To generate a diff of this commit:
cvs rdiff -u -r1.104 -r1.105 src/sys/kern/kern_ksyms.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/kern/kern_ksyms.c
diff -u src/sys/kern/kern_ksyms.c:1.104 src/sys/kern/kern_ksyms.c:1.105
--- src/sys/kern/kern_ksyms.c:1.104 Sat Sep 11 10:09:55 2021
+++ src/sys/kern/kern_ksyms.c Wed Sep 22 05:42:19 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_ksyms.c,v 1.104 2021/09/11 10:09:55 riastradh Exp $ */
+/* $NetBSD: kern_ksyms.c,v 1.105 2021/09/22 05:42:19 rin Exp $ */
/*-
* Copyright (c) 2008 The NetBSD Foundation, Inc.
@@ -73,7 +73,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_ksyms.c,v 1.104 2021/09/11 10:09:55 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_ksyms.c,v 1.105 2021/09/22 05:42:19 rin Exp $");
#if defined(_KERNEL) && defined(_KERNEL_OPT)
#include "opt_copy_symtab.h"
@@ -1406,6 +1406,7 @@ ksymsmmap(struct file *fp, off_t *offp,
return EINVAL; /* XXX ??? */
/* Success! */
+ uao_reference(ks->ks_uobj);
*advicep = UVM_ADV_SEQUENTIAL;
*uobjp = ks->ks_uobj;
*maxprotp = prot & VM_PROT_READ;
