/* Returns true if the given address is within the code segment. Generates
* error messages if it isn't.
*/
static INLINE Bool NaClCheckAddressRange(NaClPcAddress address,
NaClValidatorState* state) {
if (address >= state->codesize) {
NaClValidatorPcAddressMessage(LOG_ERROR, state, address,
"Jump to address outside code segment.\n");
return FALSE;
}
return TRUE;
}
void NaClJumpValidatorSummarize(NaClValidatorState* vstate) {
/* Check that any explicit jump is to a possible (atomic) sequence
* of disassembled instructions.
*/
NaClJumpSets* jump_sets;
NaClPcAddress addr;
size_t i;
if (vstate->quit) return;
jump_sets = &vstate->jump_sets;
NaClValidatorMessage(
LOG_INFO, vstate,
"Checking jump targets: %"NACL_PRIxNaClPcAddress
" to %"NACL_PRIxNaClPcAddress"\n",
vstate->vbase, vstate->vbase + vstate->codesize);
/* (Low level) Walk the collected sets to find address that correspond
* to branches into an atomic sequence of instructions.
*/
for (i = 0; i < jump_sets->set_array_size; ++i) {
uint8_t problem = jump_sets->actual_targets[i] &
(~jump_sets->possible_targets[i] |
jump_sets->removed_targets[i]);
if (problem) {
/* Some bit in this range is a problem, so we will convert back
* to code like the above and test each bit separately.
*/
NaClPcAddress j;
NaClPcAddress base = (i << 3);
for (j = 0; j < 8; ++j) {
addr = base + j;
if (addr < vstate->codesize) {
if (NaClAddressSetContains(jump_sets->actual_targets, addr, vstate)) {
DEBUG(NaClLog(LOG_INFO,
"Checking jump address: %"NACL_PRIxNaClPcAddress"\n",
addr));
if (!IsNaClReachableAddress(vstate, addr)) {
NaClValidatorPcAddressMessage(LOG_ERROR, vstate, addr,
"Bad jump target\n");
}
}
}
}
}
}
/* Check that all block boundaries are accessable at an aligned address. */
NaClValidatorMessage(
LOG_INFO, vstate, "Checking that basic blocks are aligned\n");
if (vstate->vbase & vstate->bundle_mask) {
NaClValidatorMessage(LOG_ERROR, vstate,
"Code segment starts at 0x%"NACL_PRIxNaClPcAddress", "
"which isn't aligned properly.\n",
vstate->vbase);
} else {
for (addr = 0; addr < vstate->codesize; addr += vstate->bundle_size) {
DEBUG(NaClLog(LOG_INFO,
"Checking block address: %"NACL_PRIxNaClPcAddress"\n",
addr));
if (!IsNaClReachableAddress(vstate, addr)) {
NaClValidatorPcAddressMessage(LOG_ERROR, vstate, addr,
"Bad basic block alignment.\n");
}
}
}
}
