Sun Jul 30 07:48:54 2023 UTC ()
netbsd32_epoll_pwait2: Early return if no event arrived;
Do not attempt to allocate 0-byte buffer by kmem_alloc(9).


(rin)
diff -r1.1 -r1.2 src/sys/compat/netbsd32/netbsd32_epoll.c
cvs diff -r1.1 -r1.2 src/sys/compat/netbsd32/netbsd32_epoll.c (expand / switch to unified diff)

--- src/sys/compat/netbsd32/netbsd32_epoll.c 2023/07/30 06:52:20 1.1
+++ src/sys/compat/netbsd32/netbsd32_epoll.c 2023/07/30 07:48:54 1.2
@@ -1,14 +1,14 @@ @@ -1,14 +1,14 @@
1/* $NetBSD: netbsd32_epoll.c,v 1.1 2023/07/30 06:52:20 rin Exp $ */ 1/* $NetBSD: netbsd32_epoll.c,v 1.2 2023/07/30 07:48:54 rin Exp $ */
2 2
3/*- 3/*-
4 * SPDX-License-Identifier: BSD-2-Clause 4 * SPDX-License-Identifier: BSD-2-Clause
5 * 5 *
6 * Copyright (c) 2007 Roman Divacky 6 * Copyright (c) 2007 Roman Divacky
7 * Copyright (c) 2014 Dmitry Chagin <dchagin@FreeBSD.org> 7 * Copyright (c) 2014 Dmitry Chagin <dchagin@FreeBSD.org>
8 * 8 *
9 * Redistribution and use in source and binary forms, with or without 9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions 10 * modification, are permitted provided that the following conditions
11 * are met: 11 * are met:
12 * 1. Redistributions of source code must retain the above copyright 12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer. 13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright 14 * 2. Redistributions in binary form must reproduce the above copyright
@@ -18,27 +18,27 @@ @@ -18,27 +18,27 @@
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE. 28 * SUCH DAMAGE.
29 */ 29 */
30#include <sys/cdefs.h> 30#include <sys/cdefs.h>
31__KERNEL_RCSID(0, "$NetBSD: netbsd32_epoll.c,v 1.1 2023/07/30 06:52:20 rin Exp $"); 31__KERNEL_RCSID(0, "$NetBSD: netbsd32_epoll.c,v 1.2 2023/07/30 07:48:54 rin Exp $");
32 32
33#include <sys/types.h> 33#include <sys/types.h>
34#include <sys/epoll.h> 34#include <sys/epoll.h>
35#include <sys/kmem.h> 35#include <sys/kmem.h>
36#include <sys/systm.h> 36#include <sys/systm.h>
37#include <sys/syscall.h> 37#include <sys/syscall.h>
38#include <sys/syscallargs.h> 38#include <sys/syscallargs.h>
39 39
40#include <compat/netbsd32/netbsd32.h> 40#include <compat/netbsd32/netbsd32.h>
41#include <compat/netbsd32/netbsd32_conv.h> 41#include <compat/netbsd32/netbsd32_conv.h>
42#include <compat/netbsd32/netbsd32_syscall.h> 42#include <compat/netbsd32/netbsd32_syscall.h>
43#include <compat/netbsd32/netbsd32_syscallargs.h> 43#include <compat/netbsd32/netbsd32_syscallargs.h>
44 44
@@ -119,27 +119,27 @@ netbsd32_epoll_pwait2(struct lwp *l, @@ -119,27 +119,27 @@ netbsd32_epoll_pwait2(struct lwp *l,
119 if (SCARG_P32(uap, sigmask) != NULL) { 119 if (SCARG_P32(uap, sigmask) != NULL) {
120 error = copyin(SCARG_P32(uap, sigmask), &ss, sizeof(ss)); 120 error = copyin(SCARG_P32(uap, sigmask), &ss, sizeof(ss));
121 if (error != 0) 121 if (error != 0)
122 return error; 122 return error;
123 123
124 ssp = &ss; 124 ssp = &ss;
125 } else 125 } else
126 ssp = NULL; 126 ssp = NULL;
127 127
128 events = kmem_alloc(maxevents * sizeof(*events), KM_SLEEP); 128 events = kmem_alloc(maxevents * sizeof(*events), KM_SLEEP);
129 129
130 error = epoll_wait_common(l, retval, SCARG(uap, epfd), events, 130 error = epoll_wait_common(l, retval, SCARG(uap, epfd), events,
131 maxevents, tsp, ssp); 131 maxevents, tsp, ssp);
132 if (error != 0) { 132 if (error != 0 || *retval == 0) {
133 kmem_free(events, maxevents * sizeof(*events)); 133 kmem_free(events, maxevents * sizeof(*events));
134 return error; 134 return error;
135 } 135 }
136 136
137 struct netbsd32_epoll_event *events32 = 137 struct netbsd32_epoll_event *events32 =
138 kmem_alloc(*retval * sizeof(*events32), KM_SLEEP); 138 kmem_alloc(*retval * sizeof(*events32), KM_SLEEP);
139 139
140 for (int i = 0; i < *retval; i++) 140 for (int i = 0; i < *retval; i++)
141 netbsd32_from_epoll_event(&events[i], &events32[i]); 141 netbsd32_from_epoll_event(&events[i], &events32[i]);
142 142
143 kmem_free(events, maxevents * sizeof(*events)); 143 kmem_free(events, maxevents * sizeof(*events));
144 144
145 error = copyout(events, SCARG_P32(uap, events), 145 error = copyout(events, SCARG_P32(uap, events),