From: Visa Hankala <v...@hankala.org>

[ Upstream commit da64ae2d35d3673233f0403b035d4c6acbf71965 ]

Use three-way comparison for address components to avoid integer
wraparound in the result of xfrm_policy_addr_delta(). This ensures
that the search trees are built and traversed correctly.

Treat IPv4 and IPv6 similarly by returning 0 when prefixlen == 0.
Prefix /0 has only one equivalence class.

Fixes: 9cf545ebd591d ("xfrm: policy: store inexact policies in a tree ordered 
by destination address")
Signed-off-by: Visa Hankala <v...@hankala.org>
Acked-by: Florian Westphal <f...@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klass...@secunet.com>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
 net/xfrm/xfrm_policy.c                     | 26 +++++++++----
 tools/testing/selftests/net/xfrm_policy.sh | 43 ++++++++++++++++++++++
 2 files changed, 61 insertions(+), 8 deletions(-)

diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 2f84136af48ab..b74f28cabe24f 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -793,15 +793,22 @@ static int xfrm_policy_addr_delta(const xfrm_address_t *a,
                                  const xfrm_address_t *b,
                                  u8 prefixlen, u16 family)
 {
+       u32 ma, mb, mask;
        unsigned int pdw, pbi;
        int delta = 0;
 
        switch (family) {
        case AF_INET:
-               if (sizeof(long) == 4 && prefixlen == 0)
-                       return ntohl(a->a4) - ntohl(b->a4);
-               return (ntohl(a->a4) & ((~0UL << (32 - prefixlen)))) -
-                      (ntohl(b->a4) & ((~0UL << (32 - prefixlen))));
+               if (prefixlen == 0)
+                       return 0;
+               mask = ~0U << (32 - prefixlen);
+               ma = ntohl(a->a4) & mask;
+               mb = ntohl(b->a4) & mask;
+               if (ma < mb)
+                       delta = -1;
+               else if (ma > mb)
+                       delta = 1;
+               break;
        case AF_INET6:
                pdw = prefixlen >> 5;
                pbi = prefixlen & 0x1f;
@@ -812,10 +819,13 @@ static int xfrm_policy_addr_delta(const xfrm_address_t *a,
                                return delta;
                }
                if (pbi) {
-                       u32 mask = ~0u << (32 - pbi);
-
-                       delta = (ntohl(a->a6[pdw]) & mask) -
-                               (ntohl(b->a6[pdw]) & mask);
+                       mask = ~0U << (32 - pbi);
+                       ma = ntohl(a->a6[pdw]) & mask;
+                       mb = ntohl(b->a6[pdw]) & mask;
+                       if (ma < mb)
+                               delta = -1;
+                       else if (ma > mb)
+                               delta = 1;
                }
                break;
        default:
diff --git a/tools/testing/selftests/net/xfrm_policy.sh 
b/tools/testing/selftests/net/xfrm_policy.sh
index 5922941e70c6c..bdf450eaf60cf 100755
--- a/tools/testing/selftests/net/xfrm_policy.sh
+++ b/tools/testing/selftests/net/xfrm_policy.sh
@@ -287,6 +287,47 @@ check_hthresh_repeat()
        return 0
 }
 
+# insert non-overlapping policies in a random order and check that
+# all of them can be fetched using the traffic selectors.
+check_random_order()
+{
+       local ns=$1
+       local log=$2
+
+       for i in $(seq 100); do
+               ip -net $ns xfrm policy flush
+               for j in $(seq 0 16 255 | sort -R); do
+                       ip -net $ns xfrm policy add dst $j.0.0.0/24 dir out 
priority 10 action allow
+               done
+               for j in $(seq 0 16 255); do
+                       if ! ip -net $ns xfrm policy get dst $j.0.0.0/24 dir 
out > /dev/null; then
+                               echo "FAIL: $log" 1>&2
+                               return 1
+                       fi
+               done
+       done
+
+       for i in $(seq 100); do
+               ip -net $ns xfrm policy flush
+               for j in $(seq 0 16 255 | sort -R); do
+                       local addr=$(printf "e000:0000:%02x00::/56" $j)
+                       ip -net $ns xfrm policy add dst $addr dir out priority 
10 action allow
+               done
+               for j in $(seq 0 16 255); do
+                       local addr=$(printf "e000:0000:%02x00::/56" $j)
+                       if ! ip -net $ns xfrm policy get dst $addr dir out > 
/dev/null; then
+                               echo "FAIL: $log" 1>&2
+                               return 1
+                       fi
+               done
+       done
+
+       ip -net $ns xfrm policy flush
+
+       echo "PASS: $log"
+       return 0
+}
+
 #check for needed privileges
 if [ "$(id -u)" -ne 0 ];then
        echo "SKIP: Need root privileges"
@@ -438,6 +479,8 @@ check_exceptions "exceptions and block policies after 
htresh change to normal"
 
 check_hthresh_repeat "policies with repeated htresh change"
 
+check_random_order ns3 "policies inserted in random order"
+
 for i in 1 2 3 4;do ip netns del ns$i;done
 
 exit $ret
-- 
2.27.0



Reply via email to