[lkml]   [2016]   [Jan]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRE: [PATCH] efi: fix out-of-bounds null overwrite vulnerability
>> What about using:
>> msg[len] = '\0';
>> to guarantee NUL termination?
> But that may leave garbage bytes in 'rcd_decode_str' in the case where
> the string isn't as long as 'len'.
> How about memset()'ing the buffer to zero and deleting the NUL
> termination line?

Looks like overkill to me. We only use this function in two places:

if (cper_dimm_err_location(cmem, rcd_decode_str))
trace_seq_printf(p, "%s", rcd_decode_str);

if (cper_dimm_err_location(&cmem, rcd_decode_str))
printk("%s%s\n", pfx, rcd_decode_str);

Neither would care if there were garbage after the NUL and before the
end of the rcd_decode_str[] array.

This buffer isn't visible to user space, so we aren't leaking data by having
garbage bytes after the NUL.


 \ /
  Last update: 2016-01-11 19:41    [W:0.039 / U:0.504 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site