kern_malloc.c revision 1.146.4.2
1 /* $NetBSD: kern_malloc.c,v 1.146.4.2 2020/04/13 08:05:03 martin 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 1.146.4.2 2020/04/13 08:05:03 martin 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 */ 84 MALLOC_DEFINE(M_DEVBUF, "devbuf", "device driver memory"); 85 MALLOC_DEFINE(M_DMAMAP, "DMA map", "bus_dma(9) structures"); 86 MALLOC_DEFINE(M_FREE, "free", "should be on free list"); 87 MALLOC_DEFINE(M_TEMP, "temp", "misc. temporary data buffers"); 88 MALLOC_DEFINE(M_RTABLE, "routetbl", "routing tables"); 89 MALLOC_DEFINE(M_FTABLE, "fragtbl", "fragment reassembly header"); 90 MALLOC_DEFINE(M_UFSMNT, "UFS mount", "UFS mount structure"); 91 MALLOC_DEFINE(M_NETADDR, "Export Host", "Export host address structure"); 92 MALLOC_DEFINE(M_MRTABLE, "mrt", "multicast routing tables"); 93 94 /* 95 * Header contains total size, including the header itself. 96 */ 97 struct malloc_header { 98 size_t mh_size; 99 #ifdef KASAN 100 size_t mh_rqsz; 101 #endif 102 } __aligned(ALIGNBYTES + 1); 103 104 void * 105 kern_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 } 150 151 void 152 kern_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 } 173 174 void * 175 kern_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
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