5.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Ondrej Mosnacek <omosnace@xxxxxxxxxx>
[ Upstream commit 9f36169912331fa035d7b73a91252d7c2512eb1a ]
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: 014ab19a69c3 ("selinux: Set socket NetLabel based on connection endpoint")
Signed-off-by: Ondrej Mosnacek <omosnace@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/ipv4/cipso_ipv4.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c
index 42eaad5e515f8..39a6f0d34208e 100644
--- a/net/ipv4/cipso_ipv4.c
+++ b/net/ipv4/cipso_ipv4.c
@@ -2015,12 +2015,16 @@ 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;
--
2.43.0
