Re: does "block: add secure discard" cause an overflow?

From: Adrian Hunter
Date: Sat Sep 04 2010 - 02:41:47 EST


Dan Carpenter wrote:
This is the commit 8d57a98ccd0b44 "block: add secure discard".

The patch adds a letter 'E' to the string in blk_fill_rwbs().
if (rw & REQ_SECURE)
rwbs[i++] = 'E';

The problem is that "rwbs" is a 6 character buffer and if all the flags
are set the we'd get "WABSME" which would put us off the end (when you
add the NUL terminator).

E goes with D which will not have either A or M, so there will not be
a rwbs with E that has more than 5 characters.


regards,
dan carpenter


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/