Module Name: src
Committed By: mrg
Date: Sat Apr 17 00:05:31 UTC 2021
Modified Files:
src/sys/kern: subr_evcnt.c
Log Message:
avoid an error in the recent sys/evcnt.h change to drop the 0
array size from evcnt_sysctl:ev_strings that clang does not like.
the previous "struct xevcnt_sysctl" was well defined as the
evcnt_sysctl with array length of 0 could be placed as the
anywhere in other structures, but with [] it must remain last
and xevcnt_sysctl then places a char array afterwards.
avoid this entirely by removing struct xevcnt_sysctl, combining
the string array + struct evcnt_sysctl size manually for the
allocation, and moving all "ev_string" accesses to be via the
new [] array.
To generate a diff of this commit:
cvs rdiff -u -r1.16 -r1.17 src/sys/kern/subr_evcnt.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/subr_evcnt.c
diff -u src/sys/kern/subr_evcnt.c:1.16 src/sys/kern/subr_evcnt.c:1.17
--- src/sys/kern/subr_evcnt.c:1.16 Thu Apr 15 00:37:31 2021
+++ src/sys/kern/subr_evcnt.c Sat Apr 17 00:05:31 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: subr_evcnt.c,v 1.16 2021/04/15 00:37:31 rin Exp $ */
+/* $NetBSD: subr_evcnt.c,v 1.17 2021/04/17 00:05:31 mrg Exp $ */
/*
* Copyright (c) 1996, 2000 Christopher G. Demetriou
@@ -77,7 +77,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: subr_evcnt.c,v 1.16 2021/04/15 00:37:31 rin Exp $");
+__KERNEL_RCSID(0, "$NetBSD: subr_evcnt.c,v 1.17 2021/04/17 00:05:31 mrg Exp $");
#include <sys/param.h>
#include <sys/evcnt.h>
@@ -214,13 +214,10 @@ evcnt_detach(struct evcnt *ev)
mutex_exit(&evcnt_lock);
}
-struct xevcnt_sysctl {
- struct evcnt_sysctl evs;
- char ev_strings[2*EVCNT_STRING_MAX];
-};
+typedef char ev_strings[2*EVCNT_STRING_MAX];
static size_t
-sysctl_fillevcnt(const struct evcnt *ev, struct xevcnt_sysctl *xevs,
+sysctl_fillevcnt(const struct evcnt *ev, struct evcnt_sysctl *evs,
size_t *copylenp)
{
const bool allowaddr = get_expose_address(curproc);
@@ -228,17 +225,17 @@ sysctl_fillevcnt(const struct evcnt *ev,
+ ev->ev_grouplen + 1 + ev->ev_namelen + 1;
const size_t len = roundup2(copylen, sizeof(uint64_t));
- if (xevs != NULL) {
- xevs->evs.ev_count = ev->ev_count;
- COND_SET_VALUE(xevs->evs.ev_addr, PTRTOUINT64(ev), allowaddr);
- COND_SET_VALUE(xevs->evs.ev_parent, PTRTOUINT64(ev->ev_parent),
+ if (evs != NULL) {
+ evs->ev_count = ev->ev_count;
+ COND_SET_VALUE(evs->ev_addr, PTRTOUINT64(ev), allowaddr);
+ COND_SET_VALUE(evs->ev_parent, PTRTOUINT64(ev->ev_parent),
allowaddr);
- xevs->evs.ev_type = ev->ev_type;
- xevs->evs.ev_grouplen = ev->ev_grouplen;
- xevs->evs.ev_namelen = ev->ev_namelen;
- xevs->evs.ev_len = len / sizeof(uint64_t);
- strcpy(xevs->evs.ev_strings, ev->ev_group);
- strcpy(xevs->evs.ev_strings + ev->ev_grouplen + 1, ev->ev_name);
+ evs->ev_type = ev->ev_type;
+ evs->ev_grouplen = ev->ev_grouplen;
+ evs->ev_namelen = ev->ev_namelen;
+ evs->ev_len = len / sizeof(uint64_t);
+ strcpy(evs->ev_strings, ev->ev_group);
+ strcpy(evs->ev_strings + ev->ev_grouplen + 1, ev->ev_name);
}
*copylenp = copylen;
@@ -248,7 +245,8 @@ sysctl_fillevcnt(const struct evcnt *ev,
static int
sysctl_doevcnt(SYSCTLFN_ARGS)
{
- struct xevcnt_sysctl *xevs0 = NULL, *xevs;
+ struct evcnt_sysctl *evs0 = NULL, *evs;
+ const size_t xevcnt_size = sizeof(*evs0) + sizeof(ev_strings);
const struct evcnt *ev;
int error;
int retries;
@@ -278,14 +276,14 @@ sysctl_doevcnt(SYSCTLFN_ARGS)
sysctl_unlock();
- if (oldp != NULL && xevs0 == NULL)
- xevs0 = kmem_zalloc(sizeof(*xevs0), KM_SLEEP);
+ if (oldp != NULL)
+ evs0 = kmem_zalloc(xevcnt_size, KM_SLEEP);
retries = 100;
retry:
dp = oldp;
len = (oldp != NULL) ? *oldlenp : 0;
- xevs = xevs0;
+ evs = evs0;
error = 0;
needed = 0;
@@ -300,22 +298,22 @@ sysctl_doevcnt(SYSCTLFN_ARGS)
continue;
/*
- * Prepare to copy. If xevs is NULL, fillevcnt will just
+ * Prepare to copy. If evs is NULL, fillevcnt will just
* how big the item is.
*/
size_t copylen;
- const size_t elem_size = sysctl_fillevcnt(ev, xevs, ©len);
+ const size_t elem_size = sysctl_fillevcnt(ev, evs, ©len);
needed += elem_size;
if (len < elem_size) {
- xevs = NULL;
+ evs = NULL;
continue;
}
- KASSERT(xevs != NULL);
- KASSERT(xevs->evs.ev_grouplen != 0);
- KASSERT(xevs->evs.ev_namelen != 0);
- KASSERT(xevs->evs.ev_strings[0] != 0);
+ KASSERT(evs != NULL);
+ KASSERT(evs->ev_grouplen != 0);
+ KASSERT(evs->ev_namelen != 0);
+ KASSERT(evs->ev_strings[0] != 0);
const uint32_t last_generation = evcnt_generation;
mutex_exit(&evcnt_lock);
@@ -325,7 +323,7 @@ sysctl_doevcnt(SYSCTLFN_ARGS)
* number. If we did the latter we'd have to zero them
* first or we'd leak random kernel memory.
*/
- error = copyout(xevs, dp, copylen);
+ error = copyout(evs, dp, copylen);
mutex_enter(&evcnt_lock);
if (error)
@@ -354,8 +352,8 @@ sysctl_doevcnt(SYSCTLFN_ARGS)
}
mutex_exit(&evcnt_lock);
- if (xevs0 != NULL)
- kmem_free(xevs0, sizeof(*xevs0));
+ if (evs0 != NULL)
+ kmem_free(evs0, xevcnt_size);
sysctl_relock();
