On 7/9/25 10:55 PM, Johannes Thumshirn wrote:
On 09.07.25 17:31, Bart Van Assche wrote:
Has it been considered to add a warning statement in blk_fill_rwbs()
that verifies that blk_fill_rwbs() does not write outside the bounds of
the rwbs array? See also the RWBS_LEN definition.
$ git grep -E "#define\sRWBS_LEN"
include/trace/events/block.h:#define RWBS_LEN 9
So even if we would have
opf = (REQ_PREFLUSH | REQ_OP_ZONE_APPEND | REQ_FUA | REQ_RAHEAD |
REQ_SYNC | REQ_META | REQ_ATOMIC);
it'll be 8 including the trailing \0 it'll be 9.
If you look closely, REQ_OP_SECURE_ERASE already is 'DE' so no changes.
It seems like my comment was not clear enough. I am aware that the
current code does not trigger a buffer overflow. Adding a length check
would help in my opinion because:
- It would catch potential future changes of blk_fill_rwbs() that
introduce a buffer overflow.
- It would document the length of the rwbs output buffer. Today there
are no references to RWBS_LEN in the blk_fill_rwbs() function -
neither in the code nor in any comments.
Thanks,
Bart.
