1/*	$NetBSD: kern_malloc.c,v 1.158 2019/11/14 16:23:52 maxv Exp $	*/
2
3/*
4 * Copyright (c) 1987, 1991, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 *	@(#)kern_malloc.c	8.4 (Berkeley) 5/20/95
32 */
33
34/*
35 * Copyright (c) 1996 Christopher G. Demetriou.  All rights reserved.
36 *
37 * Redistribution and use in source and binary forms, with or without
38 * modification, are permitted provided that the following conditions
39 * are met:
40 * 1. Redistributions of source code must retain the above copyright
41 *    notice, this list of conditions and the following disclaimer.
42 * 2. Redistributions in binary form must reproduce the above copyright
43 *    notice, this list of conditions and the following disclaimer in the
44 *    documentation and/or other materials provided with the distribution.
45 * 3. All advertising materials mentioning features or use of this software
46 *    must display the following acknowledgement:
47 *	This product includes software developed by the University of
48 *	California, Berkeley and its contributors.
49 * 4. Neither the name of the University nor the names of its contributors
50 *    may be used to endorse or promote products derived from this software
51 *    without specific prior written permission.
52 *
53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
56 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
57 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
63 * SUCH DAMAGE.
64 *
65 *	@(#)kern_malloc.c	8.4 (Berkeley) 5/20/95
66 */
67
68/*
69 * Wrapper interface for obsolete malloc(9).
70 */
71
72#include <sys/cdefs.h>
73__KERNEL_RCSID(0, "$NetBSD: kern_malloc.c,v 1.158 2019/11/14 16:23:52 maxv Exp $");
74
75#include <sys/param.h>
76#include <sys/malloc.h>
77#include <sys/kmem.h>
78#include <sys/asan.h>
79#include <sys/msan.h>
80
81/*
82 * Built-in malloc types.  Note: ought to be removed.
83 */
84MALLOC_DEFINE(M_DEVBUF, "devbuf", "device driver memory");
85MALLOC_DEFINE(M_DMAMAP, "DMA map", "bus_dma(9) structures");
86MALLOC_DEFINE(M_FREE, "free", "should be on free list");
87MALLOC_DEFINE(M_TEMP, "temp", "misc. temporary data buffers");
88MALLOC_DEFINE(M_RTABLE, "routetbl", "routing tables");
89MALLOC_DEFINE(M_FTABLE, "fragtbl", "fragment reassembly header");
90MALLOC_DEFINE(M_UFSMNT, "UFS mount", "UFS mount structure");
91MALLOC_DEFINE(M_NETADDR, "Export Host", "Export host address structure");
92MALLOC_DEFINE(M_MRTABLE, "mrt", "multicast routing tables");
93
94/*
95 * Header contains total size, including the header itself.
96 */
97struct malloc_header {
98	size_t mh_size;
99#ifdef KASAN
100	size_t mh_rqsz;
101#endif
102} __aligned(ALIGNBYTES + 1);
103
104void *
105kern_malloc(unsigned long reqsize, int flags)
106{
107	const int kmflags = (flags & M_NOWAIT) ? KM_NOSLEEP : KM_SLEEP;
108#ifdef KASAN
109	const size_t origsize = reqsize;
110#endif
111	size_t size = reqsize;
112	size_t allocsize, hdroffset;
113	struct malloc_header *mh;
114	void *p;
115
116	kasan_add_redzone(&size);
117
118	if (size >= PAGE_SIZE) {
119		if (size > (ULONG_MAX-PAGE_SIZE))
120			allocsize = ULONG_MAX;	/* this will fail later */
121		else
122			allocsize = PAGE_SIZE + size; /* for page alignment */
123		hdroffset = PAGE_SIZE - sizeof(struct malloc_header);
124	} else {
125		allocsize = sizeof(struct malloc_header) + size;
126		hdroffset = 0;
127	}
128
129	p = kmem_intr_alloc(allocsize, kmflags);
130	if (p == NULL)
131		return NULL;
132
133	kmsan_mark(p, allocsize, KMSAN_STATE_UNINIT);
134	kmsan_orig(p, allocsize, KMSAN_TYPE_MALLOC, __RET_ADDR);
135
136	if ((flags & M_ZERO) != 0) {
137		memset(p, 0, allocsize);
138	}
139	mh = (void *)((char *)p + hdroffset);
140	mh->mh_size = allocsize - hdroffset;
141#ifdef KASAN
142	mh->mh_rqsz = origsize;
143#endif
144	mh++;
145
146	kasan_mark(mh, origsize, size, KASAN_MALLOC_REDZONE);
147
148	return mh;
149}
150
151void
152kern_free(void *addr)
153{
154	struct malloc_header *mh;
155
156	mh = addr;
157	mh--;
158
159	kasan_mark(addr, mh->mh_size - sizeof(struct malloc_header),
160	    mh->mh_size - sizeof(struct malloc_header), KASAN_MALLOC_REDZONE);
161
162	if (mh->mh_size >= PAGE_SIZE + sizeof(struct malloc_header)) {
163		kmsan_mark((char *)addr - PAGE_SIZE,
164		    mh->mh_size + PAGE_SIZE - sizeof(struct malloc_header),
165		    KMSAN_STATE_INITED);
166		kmem_intr_free((char *)addr - PAGE_SIZE,
167		    mh->mh_size + PAGE_SIZE - sizeof(struct malloc_header));
168	} else {
169		kmsan_mark(mh, mh->mh_size, KMSAN_STATE_INITED);
170		kmem_intr_free(mh, mh->mh_size);
171	}
172}
173
174void *
175kern_realloc(void *curaddr, unsigned long newsize, int flags)
176{
177	struct malloc_header *mh;
178	unsigned long cursize;
179	void *newaddr;
180
181	/*
182	 * realloc() with a NULL pointer is the same as malloc().
183	 */
184	if (curaddr == NULL)
185		return malloc(newsize, ksp, flags);
186
187	/*
188	 * realloc() with zero size is the same as free().
189	 */
190	if (newsize == 0) {
191		free(curaddr, ksp);
192		return NULL;
193	}
194
195	if ((flags & M_NOWAIT) == 0) {
196		ASSERT_SLEEPABLE();
197	}
198
199	mh = curaddr;
200	mh--;
201
202#ifdef KASAN
203	cursize = mh->mh_rqsz;
204#else
205	cursize = mh->mh_size - sizeof(struct malloc_header);
206#endif
207
208	/*
209	 * If we already actually have as much as they want, we're done.
210	 */
211	if (newsize <= cursize)
212		return curaddr;
213
214	/*
215	 * Can't satisfy the allocation with the existing block.
216	 * Allocate a new one and copy the data.
217	 */
218	newaddr = malloc(newsize, ksp, flags);
219	if (__predict_false(newaddr == NULL)) {
220		/*
221		 * malloc() failed, because flags included M_NOWAIT.
222		 * Return NULL to indicate that failure.  The old
223		 * pointer is still valid.
224		 */
225		return NULL;
226	}
227	memcpy(newaddr, curaddr, cursize);
228
229	/*
230	 * We were successful: free the old allocation and return
231	 * the new one.
232	 */
233	free(curaddr, ksp);
234	return newaddr;
235}
236