xref: /freebsd/contrib/llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_procmaps_bsd.cpp (revision c66ec88fed842fbaad62c30d510644ceb7bd2d71)
1 //===-- sanitizer_procmaps_bsd.cpp ----------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // Information about the process mappings
10 // (FreeBSD, OpenBSD and NetBSD-specific parts).
11 //===----------------------------------------------------------------------===//
12 
13 #include "sanitizer_platform.h"
14 #if SANITIZER_FREEBSD || SANITIZER_NETBSD || SANITIZER_OPENBSD
15 #include "sanitizer_common.h"
16 #if SANITIZER_FREEBSD
17 #include "sanitizer_freebsd.h"
18 #endif
19 #include "sanitizer_procmaps.h"
20 
21 // clang-format off
22 #include <sys/types.h>
23 #include <sys/sysctl.h>
24 // clang-format on
25 #include <unistd.h>
26 #if SANITIZER_FREEBSD
27 #include <sys/user.h>
28 #endif
29 
30 #include <limits.h>
31 #if SANITIZER_OPENBSD
32 #define KVME_PROT_READ KVE_PROT_READ
33 #define KVME_PROT_WRITE KVE_PROT_WRITE
34 #define KVME_PROT_EXEC KVE_PROT_EXEC
35 #endif
36 
37 // Fix 'kinfo_vmentry' definition on FreeBSD prior v9.2 in 32-bit mode.
38 #if SANITIZER_FREEBSD && (SANITIZER_WORDSIZE == 32)
39 #include <osreldate.h>
40 #if __FreeBSD_version <= 902001 // v9.2
41 #define kinfo_vmentry xkinfo_vmentry
42 #endif
43 #endif
44 
45 namespace __sanitizer {
46 
47 void ReadProcMaps(ProcSelfMapsBuff *proc_maps) {
48   const int Mib[] = {
49 #if SANITIZER_FREEBSD
50     CTL_KERN,
51     KERN_PROC,
52     KERN_PROC_VMMAP,
53     getpid()
54 #elif SANITIZER_OPENBSD
55     CTL_KERN,
56     KERN_PROC_VMMAP,
57     getpid()
58 #elif SANITIZER_NETBSD
59     CTL_VM,
60     VM_PROC,
61     VM_PROC_MAP,
62     getpid(),
63     sizeof(struct kinfo_vmentry)
64 #else
65 #error "not supported"
66 #endif
67   };
68 
69   uptr Size = 0;
70   int Err = internal_sysctl(Mib, ARRAY_SIZE(Mib), NULL, &Size, NULL, 0);
71   CHECK_EQ(Err, 0);
72   CHECK_GT(Size, 0);
73 
74 #if !SANITIZER_OPENBSD
75   size_t MmapedSize = Size * 4 / 3;
76   void *VmMap = MmapOrDie(MmapedSize, "ReadProcMaps()");
77   Size = MmapedSize;
78   Err = internal_sysctl(Mib, ARRAY_SIZE(Mib), VmMap, &Size, NULL, 0);
79   CHECK_EQ(Err, 0);
80   proc_maps->data = (char *)VmMap;
81 #else
82   size_t PageSize = GetPageSize();
83   size_t MmapedSize = Size;
84   MmapedSize = ((MmapedSize - 1) / PageSize + 1) * PageSize;
85   char *Mem = (char *)MmapOrDie(MmapedSize, "ReadProcMaps()");
86   Size = 2 * Size + 10 * sizeof(struct kinfo_vmentry);
87   if (Size > 0x10000)
88     Size = 0x10000;
89   Size = (Size / sizeof(struct kinfo_vmentry)) * sizeof(struct kinfo_vmentry);
90   Err = internal_sysctl(Mib, ARRAY_SIZE(Mib), Mem, &Size, NULL, 0);
91   CHECK_EQ(Err, 0);
92   MmapedSize = Size;
93   proc_maps->data = Mem;
94 #endif
95 
96   proc_maps->mmaped_size = MmapedSize;
97   proc_maps->len = Size;
98 }
99 
100 bool MemoryMappingLayout::Next(MemoryMappedSegment *segment) {
101   CHECK(!Error()); // can not fail
102   char *last = data_.proc_self_maps.data + data_.proc_self_maps.len;
103   if (data_.current >= last)
104     return false;
105   const struct kinfo_vmentry *VmEntry =
106       (const struct kinfo_vmentry *)data_.current;
107 
108   segment->start = (uptr)VmEntry->kve_start;
109   segment->end = (uptr)VmEntry->kve_end;
110   segment->offset = (uptr)VmEntry->kve_offset;
111 
112   segment->protection = 0;
113   if ((VmEntry->kve_protection & KVME_PROT_READ) != 0)
114     segment->protection |= kProtectionRead;
115   if ((VmEntry->kve_protection & KVME_PROT_WRITE) != 0)
116     segment->protection |= kProtectionWrite;
117   if ((VmEntry->kve_protection & KVME_PROT_EXEC) != 0)
118     segment->protection |= kProtectionExecute;
119 
120 #if !SANITIZER_OPENBSD
121   if (segment->filename != NULL && segment->filename_size > 0) {
122     internal_snprintf(segment->filename,
123                       Min(segment->filename_size, (uptr)PATH_MAX), "%s",
124                       VmEntry->kve_path);
125   }
126 #endif
127 
128 #if SANITIZER_FREEBSD
129   data_.current += VmEntry->kve_structsize;
130 #else
131   data_.current += sizeof(*VmEntry);
132 #endif
133 
134   return true;
135 }
136 
137 } // namespace __sanitizer
138 
139 #endif
140