diff options
| author | Martin KaFai Lau <martin.lau@kernel.org> | 2023-10-09 15:35:00 -0700 |
|---|---|---|
| committer | Martin KaFai Lau <martin.lau@kernel.org> | 2023-10-09 16:28:37 -0700 |
| commit | 1ef09e1281a1add0a86ecd594f748d7fb8bfd78e (patch) | |
| tree | 1d0dc82af40e4622f899322f070c6ac30b64ac39 /net | |
| parent | 1be84ca53ca0421c781f9ec007cd8bccbb58f763 (diff) | |
| parent | b0f7a8ca11795541f09060ccf583a341a9c94d5f (diff) | |
Merge branch 'bpf: Fix src IP addr related limitation in bpf_*_fib_lookup()'
Martynas Pumputis says:
====================
The patchset fixes the limitation of bpf_*_fib_lookup() helper, which
prevents it from being used in BPF dataplanes with network interfaces
which have more than one IP addr. See the first patch for more details.
Thanks!
* v2->v3: Address Martin KaFai Lau's feedback
* v1->v2: Use IPv6 stubs to fix compilation when CONFIG_IPV6=m.
====================
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/core/filter.c | 18 | ||||
| -rw-r--r-- | net/ipv6/af_inet6.c | 1 |
2 files changed, 18 insertions, 1 deletions
diff --git a/net/core/filter.c b/net/core/filter.c index a094694899c9..3880bf0b740d 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -5850,6 +5850,9 @@ static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params, params->rt_metric = res.fi->fib_priority; params->ifindex = dev->ifindex; + if (flags & BPF_FIB_LOOKUP_SRC) + params->ipv4_src = fib_result_prefsrc(net, &res); + /* xdp and cls_bpf programs are run in RCU-bh so * rcu_read_lock_bh is not needed here */ @@ -5992,6 +5995,18 @@ static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params, params->rt_metric = res.f6i->fib6_metric; params->ifindex = dev->ifindex; + if (flags & BPF_FIB_LOOKUP_SRC) { + if (res.f6i->fib6_prefsrc.plen) { + *src = res.f6i->fib6_prefsrc.addr; + } else { + err = ipv6_bpf_stub->ipv6_dev_get_saddr(net, dev, + &fl6.daddr, 0, + src); + if (err) + return BPF_FIB_LKUP_RET_NO_SRC_ADDR; + } + } + if (flags & BPF_FIB_LOOKUP_SKIP_NEIGH) goto set_fwd_params; @@ -6010,7 +6025,8 @@ set_fwd_params: #endif #define BPF_FIB_LOOKUP_MASK (BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT | \ - BPF_FIB_LOOKUP_SKIP_NEIGH | BPF_FIB_LOOKUP_TBID) + BPF_FIB_LOOKUP_SKIP_NEIGH | BPF_FIB_LOOKUP_TBID | \ + BPF_FIB_LOOKUP_SRC) BPF_CALL_4(bpf_xdp_fib_lookup, struct xdp_buff *, ctx, struct bpf_fib_lookup *, params, int, plen, u32, flags) diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c index c6ad0d6e99b5..6337fb4504fd 100644 --- a/net/ipv6/af_inet6.c +++ b/net/ipv6/af_inet6.c @@ -1061,6 +1061,7 @@ static const struct ipv6_bpf_stub ipv6_bpf_stub_impl = { .udp6_lib_lookup = __udp6_lib_lookup, .ipv6_setsockopt = do_ipv6_setsockopt, .ipv6_getsockopt = do_ipv6_getsockopt, + .ipv6_dev_get_saddr = ipv6_dev_get_saddr, }; static int __init inet6_init(void) |