cipso: fix total option length computation

As evident from the definition of ip_options_get(), the IP option
IPOPT_END is used to pad the IP option data array, not IPOPT_NOP. Yet
the loop that walks the IP options to determine the total IP options
length in cipso_v4_delopt() doesn't take IPOPT_END into account.

Fix it by recognizing the IPOPT_END value as the end of actual options.

Fixes: 014ab19a69 ("selinux: Set socket NetLabel based on connection endpoint")
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Ondrej Mosnacek 2024-06-07 18:07:52 +02:00 committed by David S. Miller
parent 4467c09bc7
commit 9f36169912

View File

@ -2013,12 +2013,16 @@ static int cipso_v4_delopt(struct ip_options_rcu __rcu **opt_ptr)
* from there we can determine the new total option length */
iter = 0;
optlen_new = 0;
while (iter < opt->opt.optlen)
if (opt->opt.__data[iter] != IPOPT_NOP) {
while (iter < opt->opt.optlen) {
if (opt->opt.__data[iter] == IPOPT_END) {
break;
} else if (opt->opt.__data[iter] == IPOPT_NOP) {
iter++;
} else {
iter += opt->opt.__data[iter + 1];
optlen_new = iter;
} else
iter++;
}
}
hdr_delta = opt->opt.optlen;
opt->opt.optlen = (optlen_new + 3) & ~3;
hdr_delta -= opt->opt.optlen;