Philippe Mathieu-Daudé <[email protected]> writes:
> On 4/18/19 4:53 PM, Markus Armbruster wrote:
>> "Debugging with GDB / Appendix E GDB Remote Serial Protocol /
>> Overview" specifies "The printable characters '#' and '$' or with a
>> numeric value greater than 126 must not be used." gdb_read_byte()
>> only rejects values < 32. This is wrong. Impact depends on the caller:
>>
>> * gdb_handlesig() passes a char. Incorrectly accepts '#', '$' and
>> '\127'.
>>
>> * gdb_chr_receive() passes an uint8_t. Additionally accepts
>> characters with the most-significant bit set.
>>
>> Correct the validity check to match the specification.
>>
>> Signed-off-by: Markus Armbruster <[email protected]>
>> ---
>> gdbstub.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/gdbstub.c b/gdbstub.c
>> index d54abd17cc..a6dce1b027 100644
>> --- a/gdbstub.c
>> +++ b/gdbstub.c
>> @@ -2064,7 +2064,7 @@ static void gdb_read_byte(GDBState *s, int ch)
>> }
>> break;
>> case RS_GETLINE_RLE:
>> - if (ch < ' ') {
>
> Can you add a comment referring to the ""Debugging with GDB / Appendix E
> GDB Remote Serial Protocol / Overview" here?
Like this?
case RS_GETLINE_RLE:
/*
* Run-length encoding is explained in "Debugging with GDB /
* Appendix E GDB Remote Serial Protocol / Overview".
*/
if (ch < ' ') {
> Reviewed-by: Philippe Mathieu-Daudé <[email protected]>
Thanks!
>> + if (ch < ' ' || ch == '#' || ch == '$' || ch > 126) {
>> /* invalid RLE count encoding */
>> trace_gdbstub_err_invalid_repeat((uint8_t)ch);
>> s->state = RS_GETLINE;
>>
