diff options
| author | Miod Vallat <miod@cvs.openbsd.org> | 2007-04-12 21:47:47 +0000 |
|---|---|---|
| committer | Miod Vallat <miod@cvs.openbsd.org> | 2007-04-12 21:47:47 +0000 |
| commit | 0003df26691626da39d85b2ee1accdeb534684b2 (patch) | |
| tree | 4e1ebec7624e9ff753a1e1c6c4a8f0fb8151aec0 /sys/uvm/uvm_init.c | |
| parent | c96c8d60569ece4c81cfeed0d77047930008fb2d (diff) | |
Allow machine-dependant overrides for the ``deadbeef'' sentinel values,
and make sure that nothing can ever be mapped at theses addresses.
Only i386 overrides the default for now.
From mickey@, ok art@ miod@
Diffstat (limited to 'sys/uvm/uvm_init.c')
| -rw-r--r-- | sys/uvm/uvm_init.c | 19 |
1 files changed, 18 insertions, 1 deletions
diff --git a/sys/uvm/uvm_init.c b/sys/uvm/uvm_init.c index 92f14bcccbc..2f33534d941 100644 --- a/sys/uvm/uvm_init.c +++ b/sys/uvm/uvm_init.c @@ -1,4 +1,4 @@ -/* $OpenBSD: uvm_init.c,v 1.13 2006/07/13 22:51:26 deraadt Exp $ */ +/* $OpenBSD: uvm_init.c,v 1.14 2007/04/12 21:47:46 miod Exp $ */ /* $NetBSD: uvm_init.c,v 1.14 2000/06/27 17:29:23 mrg Exp $ */ /* @@ -153,6 +153,23 @@ uvm_init() uvm_km_page_init(); /* + * reserve some unmapped space for malloc/pool use after free usage + */ +#ifdef DEADBEEF0 + kvm_start = DEADBEEF0 - PAGE_SIZE; + if (uvm_map(kernel_map, &kvm_start, 3 * PAGE_SIZE, + NULL, UVM_UNKNOWN_OFFSET, 0, UVM_MAPFLAG(UVM_PROT_NONE, + UVM_PROT_NONE, UVM_INH_NONE, UVM_ADV_RANDOM, UVM_FLAG_FIXED))) + panic("uvm_init: cannot reserve dead beef @0x%x\n", DEADBEEF0); +#endif +#ifdef DEADBEEF1 + kvm_start = DEADBEEF1 - PAGE_SIZE; + if (uvm_map(kernel_map, &kvm_start, 3 * PAGE_SIZE, + NULL, UVM_UNKNOWN_OFFSET, 0, UVM_MAPFLAG(UVM_PROT_NONE, + UVM_PROT_NONE, UVM_INH_NONE, UVM_ADV_RANDOM, UVM_FLAG_FIXED))) + panic("uvm_init: cannot reserve dead beef @0x%x\n", DEADBEEF1); +#endif + /* * done! */ |