| Message ID | 20190924140128.19394-1-Jason@zx2c4.com |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | [v2] ipv6: do not free rt if FIB_LOOKUP_NOREF is set on suppress rule | expand |
On Tue, Sep 24, 2019 at 7:01 AM Jason A. Donenfeld <Jason@zx2c4.com> wrote: > > Commit 7d9e5f422150 removed references from certain dsts, but accounting > for this never translated down into the fib6 suppression code. This bug > was triggered by WireGuard users who use wg-quick(8), which uses the > "suppress-prefix" directive to ip-rule(8) for routing all of their > internet traffic without routing loops. The test case added here > causes the reference underflow by causing packets to evaluate a suppress > rule. > > Cc: stable@vger.kernel.org > Fixes: 7d9e5f422150 ("ipv6: convert major tx path to use RT6_LOOKUP_F_DST_NOREF") > Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> > --- Acked-by: Wei Wang <weiwan@google.com> Good catch. Thanks for the fix. > net/ipv6/fib6_rules.c | 3 ++- > tools/testing/selftests/net/fib_tests.sh | 17 ++++++++++++++++- > 2 files changed, 18 insertions(+), 2 deletions(-) > > diff --git a/net/ipv6/fib6_rules.c b/net/ipv6/fib6_rules.c > index d22b6c140f23..f9e8fe3ff0c5 100644 > --- a/net/ipv6/fib6_rules.c > +++ b/net/ipv6/fib6_rules.c > @@ -287,7 +287,8 @@ static bool fib6_rule_suppress(struct fib_rule *rule, struct fib_lookup_arg *arg > return false; > > suppress_route: > - ip6_rt_put(rt); > + if (!(arg->flags & FIB_LOOKUP_NOREF)) > + ip6_rt_put(rt); > return true; > } > > diff --git a/tools/testing/selftests/net/fib_tests.sh b/tools/testing/selftests/net/fib_tests.sh > index 4465fc2dae14..c2c5f2bf0f95 100755 > --- a/tools/testing/selftests/net/fib_tests.sh > +++ b/tools/testing/selftests/net/fib_tests.sh > @@ -9,7 +9,7 @@ ret=0 > ksft_skip=4 > > # all tests in this script. Can be overridden with -t option > -TESTS="unregister down carrier nexthop ipv6_rt ipv4_rt ipv6_addr_metric ipv4_addr_metric ipv6_route_metrics ipv4_route_metrics ipv4_route_v6_gw rp_filter" > +TESTS="unregister down carrier nexthop suppress ipv6_rt ipv4_rt ipv6_addr_metric ipv4_addr_metric ipv6_route_metrics ipv4_route_metrics ipv4_route_v6_gw rp_filter" > > VERBOSE=0 > PAUSE_ON_FAIL=no > @@ -614,6 +614,20 @@ fib_nexthop_test() > cleanup > } > > +fib_suppress_test() > +{ > + $IP link add dummy1 type dummy > + $IP link set dummy1 up > + $IP -6 route add default dev dummy1 > + $IP -6 rule add table main suppress_prefixlength 0 > + ping -f -c 1000 -W 1 1234::1 || true > + $IP -6 rule del table main suppress_prefixlength 0 > + $IP link del dummy1 > + > + # If we got here without crashing, we're good. > + return 0 > +} > + > ################################################################################ > # Tests on route add and replace > > @@ -1591,6 +1605,7 @@ do > fib_carrier_test|carrier) fib_carrier_test;; > fib_rp_filter_test|rp_filter) fib_rp_filter_test;; > fib_nexthop_test|nexthop) fib_nexthop_test;; > + fib_suppress_test|suppress) fib_suppress_test;; > ipv6_route_test|ipv6_rt) ipv6_route_test;; > ipv4_route_test|ipv4_rt) ipv4_route_test;; > ipv6_addr_metric) ipv6_addr_metric_test;; > -- > 2.21.0 >
From: "Jason A. Donenfeld" <Jason@zx2c4.com> Date: Tue, 24 Sep 2019 16:01:28 +0200 > Commit 7d9e5f422150 removed references from certain dsts, but accounting > for this never translated down into the fib6 suppression code. This bug > was triggered by WireGuard users who use wg-quick(8), which uses the > "suppress-prefix" directive to ip-rule(8) for routing all of their > internet traffic without routing loops. The test case added here > causes the reference underflow by causing packets to evaluate a suppress > rule. > > Cc: stable@vger.kernel.org Please don't CC: stable for networking fixes, I handle these manually as per the netdev FAQ. > Fixes: 7d9e5f422150 ("ipv6: convert major tx path to use RT6_LOOKUP_F_DST_NOREF") > Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Applied and queued up for -stable, thanks.
On 9/24/19 8:01 AM, Jason A. Donenfeld wrote: > Commit 7d9e5f422150 removed references from certain dsts, but accounting > for this never translated down into the fib6 suppression code. This bug > was triggered by WireGuard users who use wg-quick(8), which uses the > "suppress-prefix" directive to ip-rule(8) for routing all of their > internet traffic without routing loops. The test case added here > causes the reference underflow by causing packets to evaluate a suppress > rule. > > Cc: stable@vger.kernel.org > Fixes: 7d9e5f422150 ("ipv6: convert major tx path to use RT6_LOOKUP_F_DST_NOREF") > Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> > --- > net/ipv6/fib6_rules.c | 3 ++- > tools/testing/selftests/net/fib_tests.sh | 17 ++++++++++++++++- > 2 files changed, 18 insertions(+), 2 deletions(-) Thanks for adding the test case. Reviewed-by: David Ahern <dsahern@gmail.com>
diff --git a/net/ipv6/fib6_rules.c b/net/ipv6/fib6_rules.c index d22b6c140f23..f9e8fe3ff0c5 100644 --- a/net/ipv6/fib6_rules.c +++ b/net/ipv6/fib6_rules.c @@ -287,7 +287,8 @@ static bool fib6_rule_suppress(struct fib_rule *rule, struct fib_lookup_arg *arg return false; suppress_route: - ip6_rt_put(rt); + if (!(arg->flags & FIB_LOOKUP_NOREF)) + ip6_rt_put(rt); return true; } diff --git a/tools/testing/selftests/net/fib_tests.sh b/tools/testing/selftests/net/fib_tests.sh index 4465fc2dae14..c2c5f2bf0f95 100755 --- a/tools/testing/selftests/net/fib_tests.sh +++ b/tools/testing/selftests/net/fib_tests.sh @@ -9,7 +9,7 @@ ret=0 ksft_skip=4 # all tests in this script. Can be overridden with -t option -TESTS="unregister down carrier nexthop ipv6_rt ipv4_rt ipv6_addr_metric ipv4_addr_metric ipv6_route_metrics ipv4_route_metrics ipv4_route_v6_gw rp_filter" +TESTS="unregister down carrier nexthop suppress ipv6_rt ipv4_rt ipv6_addr_metric ipv4_addr_metric ipv6_route_metrics ipv4_route_metrics ipv4_route_v6_gw rp_filter" VERBOSE=0 PAUSE_ON_FAIL=no @@ -614,6 +614,20 @@ fib_nexthop_test() cleanup } +fib_suppress_test() +{ + $IP link add dummy1 type dummy + $IP link set dummy1 up + $IP -6 route add default dev dummy1 + $IP -6 rule add table main suppress_prefixlength 0 + ping -f -c 1000 -W 1 1234::1 || true + $IP -6 rule del table main suppress_prefixlength 0 + $IP link del dummy1 + + # If we got here without crashing, we're good. + return 0 +} + ################################################################################ # Tests on route add and replace @@ -1591,6 +1605,7 @@ do fib_carrier_test|carrier) fib_carrier_test;; fib_rp_filter_test|rp_filter) fib_rp_filter_test;; fib_nexthop_test|nexthop) fib_nexthop_test;; + fib_suppress_test|suppress) fib_suppress_test;; ipv6_route_test|ipv6_rt) ipv6_route_test;; ipv4_route_test|ipv4_rt) ipv4_route_test;; ipv6_addr_metric) ipv6_addr_metric_test;;
Commit 7d9e5f422150 removed references from certain dsts, but accounting for this never translated down into the fib6 suppression code. This bug was triggered by WireGuard users who use wg-quick(8), which uses the "suppress-prefix" directive to ip-rule(8) for routing all of their internet traffic without routing loops. The test case added here causes the reference underflow by causing packets to evaluate a suppress rule. Cc: stable@vger.kernel.org Fixes: 7d9e5f422150 ("ipv6: convert major tx path to use RT6_LOOKUP_F_DST_NOREF") Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> --- net/ipv6/fib6_rules.c | 3 ++- tools/testing/selftests/net/fib_tests.sh | 17 ++++++++++++++++- 2 files changed, 18 insertions(+), 2 deletions(-)