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POISON only integer pointers

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For architectures that can't manipulate pointers like integers, don't
try XORing them like this.  It's not ideal -- perhaps we should have
"else" branches to these tests.
This commit is contained in:
Nathaniel Filardo
2019-07-15 16:14:36 +01:00
parent 0d6f708166
commit 2fa60c719f
1 changed files with 13 additions and 9 deletions
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22
src/mem/metaslab.h
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@@ -109,11 +109,12 @@ namespace snmalloc
/// simple corruptions.
static SNMALLOC_FAST_PATH void store_next(void* p, void* head)
{
#ifndef CHECK_CLIENT
*static_cast<void**>(p) = head;
#else
*static_cast<void**>(p) = head;
*(static_cast<uintptr_t*>(p) + 1) = address_cast(head) ^ POISON;
#if defined(CHECK_CLIENT)
if constexpr (aal_supports<IntegerPointers>)
{
*(static_cast<uintptr_t*>(p) + 1) = address_cast(head) ^ POISON;
}
#endif
}
@@ -121,11 +122,14 @@ namespace snmalloc
/// In Debug checks for simple corruptions.
static SNMALLOC_FAST_PATH void* follow_next(void* node)
{
#ifdef CHECK_CLIENT
uintptr_t next = *static_cast<uintptr_t*>(node);
uintptr_t chk = *(static_cast<uintptr_t*>(node) + 1);
if ((next ^ chk) != POISON)
error("Detected memory corruption. Use-after-free.");
#if defined(CHECK_CLIENT)
if constexpr (aal_supports<IntegerPointers>)
{
uintptr_t next = *static_cast<uintptr_t*>(node);
uintptr_t chk = *(static_cast<uintptr_t*>(node) + 1);
if ((next ^ chk) != POISON)
error("Detected memory corruption. Use-after-free.");
}
#endif
return *static_cast<void**>(node);
}