OpenBSD/x86: Better executable memory allocation for W^X mode.

This commit is contained in:
Mike Pall 2015-01-17 12:55:04 +01:00
parent 86913b9bbf
commit b876d6dada

View File

@ -145,7 +145,7 @@ static void mcode_free(jit_State *J, void *p, size_t sz)
/* -- MCode area protection ----------------------------------------------- */ /* -- MCode area protection ----------------------------------------------- */
/* Define this ONLY if the page protection twiddling becomes a bottleneck. */ /* Define this ONLY if page protection twiddling becomes a bottleneck. */
#ifdef LUAJIT_UNPROTECT_MCODE #ifdef LUAJIT_UNPROTECT_MCODE
/* It's generally considered to be a potential security risk to have /* It's generally considered to be a potential security risk to have
@ -252,7 +252,20 @@ static void *mcode_alloc(jit_State *J, size_t sz)
#else #else
/* All memory addresses are reachable by relative jumps. */ /* All memory addresses are reachable by relative jumps. */
#define mcode_alloc(J, sz) mcode_alloc_at((J), 0, (sz), MCPROT_GEN) static void *mcode_alloc(jit_State *J, size_t sz)
{
#ifdef __OpenBSD__
/* Allow better executable memory allocation for OpenBSD W^X mode. */
void *p = mcode_alloc_at(J, 0, sz, MCPROT_RUN);
if (p && mcode_setprot(p, sz, MCPROT_GEN)) {
mcode_free(J, p, sz);
return NULL;
}
return p;
#else
return mcode_alloc_at(J, 0, sz, MCPROT_GEN);
#endif
}
#endif #endif