1 .\" Copyright (c) 2005 Christian Brueffer
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32 .Nd "memory allocator for debugging purposes"
34 .Cd "options DEBUG_MEMGUARD"
37 is a simple and small replacement memory allocator designed
38 to help detect tamper-after-free scenarios.
39 These problems are more and more common and likely with
40 multithreaded kernels where race conditions are more prevalent.
49 for a particular malloc type.
53 allocations by default.
55 .Bl -tag -width ".Pa src/sys/kern/kern_malloc.c" -compact
56 .It Pa src/sys/kern/kern_malloc.c
57 File to replace the malloc type in
60 The following steps are necessary to use
66 option into your kernel config.
69 .Pa src/sys/kern/kern_malloc.c
70 in your favourite editor.
71 Look for lines containing
72 .Dq Li "XXX CHANGEME!"
75 with the appropriate malloc type.
76 This might require additional but small/simple
78 (e.g., if the malloc type is declared out of scope).
80 Build and install your kernel.
82 .Va vm.memguard_divisor
83 boot-time tunable, which is used to scale how much of
92 value can be obtained via the
110 .An Bosko Milekic Aq bmilekic@FreeBSD.org .
111 This manual page was written by
112 .An Christian Brueffer Aq brueffer@FreeBSD.org .
114 Currently, it is not possible to override UMA