commit
e237ec37ec154564f8690c5bd1795339955eeef9 upstream.
Check that length specified in a component of a symlink fits in the
input buffer we are reading. Also properly ignore component length for
component types that do not use it. Otherwise we read memory after end
of buffer for corrupted udf image.
Reported-by: Carl Henrik Lunde <chlunde@ping.uio.no>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
tolen--;
while (elen < fromlen) {
pc = (struct pathComponent *)(from + elen);
tolen--;
while (elen < fromlen) {
pc = (struct pathComponent *)(from + elen);
+ elen += sizeof(struct pathComponent);
switch (pc->componentType) {
case 1:
/*
* Symlink points to some place which should be agreed
* upon between originator and receiver of the media. Ignore.
*/
switch (pc->componentType) {
case 1:
/*
* Symlink points to some place which should be agreed
* upon between originator and receiver of the media. Ignore.
*/
- if (pc->lengthComponentIdent > 0)
+ if (pc->lengthComponentIdent > 0) {
+ elen += pc->lengthComponentIdent;
/* Fall through */
case 2:
if (tolen == 0)
/* Fall through */
case 2:
if (tolen == 0)
/* that would be . - just ignore */
break;
case 5:
/* that would be . - just ignore */
break;
case 5:
+ elen += pc->lengthComponentIdent;
+ if (elen > fromlen)
+ return -EIO;
comp_len = udf_get_filename(sb, pc->componentIdent,
pc->lengthComponentIdent,
p, tolen);
comp_len = udf_get_filename(sb, pc->componentIdent,
pc->lengthComponentIdent,
p, tolen);
- elen += sizeof(struct pathComponent) + pc->lengthComponentIdent;
}
if (p > to + 1)
p[-1] = '\0';
}
if (p > to + 1)
p[-1] = '\0';