netlabel: out of bound access in cipso_v4_validate()

syzkaller found another out of bound access in ip_options_compile(),
or more exactly in cipso_v4_validate()

Fixes: 20e2a86485 ("cipso: handle CIPSO options correctly when NetLabel is disabled")
Fixes: 446fda4f26 ("[NetLabel]: CIPSOv4 engine")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov  <dvyukov@google.com>
Cc: Paul Moore <paul@paul-moore.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2017-02-03 00:03:26 -08:00 committed by David S. Miller
parent 34b2cef20f
commit d71b789688
2 changed files with 8 additions and 0 deletions

View file

@ -309,6 +309,10 @@ static inline int cipso_v4_validate(const struct sk_buff *skb,
}
for (opt_iter = 6; opt_iter < opt_len;) {
if (opt_iter + 1 == opt_len) {
err_offset = opt_iter;
goto out;
}
tag_len = opt[opt_iter + 1];
if ((tag_len == 0) || (tag_len > (opt_len - opt_iter))) {
err_offset = opt_iter + 1;

View file

@ -1587,6 +1587,10 @@ int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option)
goto validate_return_locked;
}
if (opt_iter + 1 == opt_len) {
err_offset = opt_iter;
goto validate_return_locked;
}
tag_len = tag[1];
if (tag_len > (opt_len - opt_iter)) {
err_offset = opt_iter + 1;