kern_malloc.c revision 1.146.4.1
1 /* $NetBSD: kern_malloc.c,v 1.146.4.1 2019/06/10 22:09:03 christos 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 1.146.4.1 2019/06/10 22:09:03 christos Exp $"); 74 75 #include <sys/param.h> 76 #include <sys/malloc.h> 77 #include <sys/kmem.h> 78 #include <sys/asan.h> 79 80 /* 81 * Built-in malloc types. Note: ought to be removed. 82 */ 83 MALLOC_DEFINE(M_DEVBUF, "devbuf", "device driver memory"); 84 MALLOC_DEFINE(M_DMAMAP, "DMA map", "bus_dma(9) structures"); 85 MALLOC_DEFINE(M_FREE, "free", "should be on free list"); 86 MALLOC_DEFINE(M_TEMP, "temp", "misc. temporary data buffers"); 87 MALLOC_DEFINE(M_RTABLE, "routetbl", "routing tables"); 88 MALLOC_DEFINE(M_FTABLE, "fragtbl", "fragment reassembly header"); 89 MALLOC_DEFINE(M_UFSMNT, "UFS mount", "UFS mount structure"); 90 MALLOC_DEFINE(M_NETADDR, "Export Host", "Export host address structure"); 91 MALLOC_DEFINE(M_MRTABLE, "mrt", "multicast routing tables"); 92 93 /* 94 * Header contains total size, including the header itself. 95 */ 96 struct malloc_header { 97 size_t mh_size; 98 #ifdef KASAN 99 size_t mh_rqsz; 100 #endif 101 } __aligned(ALIGNBYTES + 1); 102 103 void * 104 kern_malloc(unsigned long reqsize, int flags) 105 { 106 const int kmflags = (flags & M_NOWAIT) ? KM_NOSLEEP : KM_SLEEP; 107 #ifdef KASAN 108 const size_t origsize = reqsize; 109 #endif 110 size_t size = reqsize; 111 size_t allocsize, hdroffset; 112 struct malloc_header *mh; 113 void *p; 114 115 kasan_add_redzone(&size); 116 117 if (size >= PAGE_SIZE) { 118 if (size > (ULONG_MAX-PAGE_SIZE)) 119 allocsize = ULONG_MAX; /* this will fail later */ 120 else 121 allocsize = PAGE_SIZE + size; /* for page alignment */ 122 hdroffset = PAGE_SIZE - sizeof(struct malloc_header); 123 } else { 124 allocsize = sizeof(struct malloc_header) + size; 125 hdroffset = 0; 126 } 127 128 p = kmem_intr_alloc(allocsize, kmflags); 129 if (p == NULL) 130 return NULL; 131 132 if ((flags & M_ZERO) != 0) { 133 memset(p, 0, allocsize); 134 } 135 mh = (void *)((char *)p + hdroffset); 136 mh->mh_size = allocsize - hdroffset; 137 #ifdef KASAN 138 mh->mh_rqsz = origsize; 139 #endif 140 mh++; 141 142 kasan_mark(mh, origsize, size, KASAN_MALLOC_REDZONE); 143 144 return mh; 145 } 146 147 void 148 kern_free(void *addr) 149 { 150 struct malloc_header *mh; 151 152 mh = addr; 153 mh--; 154 155 kasan_mark(addr, mh->mh_size - sizeof(struct malloc_header), 156 mh->mh_size - sizeof(struct malloc_header), KASAN_MALLOC_REDZONE); 157 158 if (mh->mh_size >= PAGE_SIZE + sizeof(struct malloc_header)) 159 kmem_intr_free((char *)addr - PAGE_SIZE, 160 mh->mh_size + PAGE_SIZE - sizeof(struct malloc_header)); 161 else 162 kmem_intr_free(mh, mh->mh_size); 163 } 164 165 void * 166 kern_realloc(void *curaddr, unsigned long newsize, int flags) 167 { 168 struct malloc_header *mh; 169 unsigned long cursize; 170 void *newaddr; 171 172 /* 173 * realloc() with a NULL pointer is the same as malloc(). 174 */ 175 if (curaddr == NULL) 176 return malloc(newsize, ksp, flags); 177 178 /* 179 * realloc() with zero size is the same as free(). 180 */ 181 if (newsize == 0) { 182 free(curaddr, ksp); 183 return NULL; 184 } 185 186 if ((flags & M_NOWAIT) == 0) { 187 ASSERT_SLEEPABLE(); 188 } 189 190 mh = curaddr; 191 mh--; 192 193 #ifdef KASAN 194 cursize = mh->mh_rqsz; 195 #else 196 cursize = mh->mh_size - sizeof(struct malloc_header); 197 #endif 198 199 /* 200 * If we already actually have as much as they want, we're done. 201 */ 202 if (newsize <= cursize) 203 return curaddr; 204 205 /* 206 * Can't satisfy the allocation with the existing block. 207 * Allocate a new one and copy the data. 208 */ 209 newaddr = malloc(newsize, ksp, flags); 210 if (__predict_false(newaddr == NULL)) { 211 /* 212 * malloc() failed, because flags included M_NOWAIT. 213 * Return NULL to indicate that failure. The old 214 * pointer is still valid. 215 */ 216 return NULL; 217 } 218 memcpy(newaddr, curaddr, cursize); 219 220 /* 221 * We were successful: free the old allocation and return 222 * the new one. 223 */ 224 free(curaddr, ksp); 225 return newaddr; 226 } 227
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