asan: assert (addr_ranges) <= (start)

That assert would be more obvious if it were reported as
"addr_ranges <= end_ranges".  Fix that by using the obvious variable
in the final loop.  Stop the assertion by using a signed comparison:
It's possible for the rounding up of the arange pointer to exceed the
end of the block when the block size is fuzzed.

	* dwarf.c (display_debug_aranges): Use "end_ranges" in loop
	displaying ranges rather that "start".  Simplify rounding up
	to 2*address_size boundary.  Use signed comparison in loop.
This commit is contained in:
Alan Modra 2021-11-03 14:50:18 +10:30
parent 0a129eb19a
commit 359c74415c

View File

@ -7192,7 +7192,6 @@ display_debug_aranges (struct dwarf_section *section,
dwarf_vma address;
unsigned long sec_off;
unsigned char address_size;
int excess;
unsigned int offset_size;
unsigned char *end_ranges;
@ -7277,22 +7276,22 @@ display_debug_aranges (struct dwarf_section *section,
addr_ranges = hdrptr;
/* Must pad to an alignment boundary that is twice the address size. */
excess = (hdrptr - start) % (2 * address_size);
if (excess)
addr_ranges += (2 * address_size) - excess;
addr_ranges += (2 * address_size - 1
- (hdrptr - start - 1) % (2 * address_size));
start = end_ranges;
while (2u * address_size <= (size_t) (start - addr_ranges))
while (2 * address_size <= end_ranges - addr_ranges)
{
SAFE_BYTE_GET_AND_INC (address, addr_ranges, address_size, start);
SAFE_BYTE_GET_AND_INC (length, addr_ranges, address_size, start);
SAFE_BYTE_GET_AND_INC (address, addr_ranges, address_size,
end_ranges);
SAFE_BYTE_GET_AND_INC (length, addr_ranges, address_size,
end_ranges);
printf (" ");
print_dwarf_vma (address, address_size);
print_dwarf_vma (length, address_size);
putchar ('\n');
}
start = end_ranges;
}
printf ("\n");