diff options
| author | Justin Iurman <justin.iurman@uliege.be> | 2024-02-19 14:52:54 +0100 |
|---|---|---|
| committer | Paolo Abeni <pabeni@redhat.com> | 2024-02-22 09:28:03 +0100 |
| commit | f198d933c2e4f8f89e0620fbaf1ea7eac384a0eb (patch) | |
| tree | 52e851fa5eb318d30a1e410e2b557ebf651a7e4d | |
| parent | 7d2a894d7f487dcb894df023e9d3014cf5b93fe5 (diff) | |
Fix write to cloned skb in ipv6_hop_ioam()
ioam6_fill_trace_data() writes inside the skb payload without ensuring
it's writeable (e.g., not cloned). This function is called both from the
input and output path. The output path (ioam6_iptunnel) already does the
check. This commit provides a fix for the input path, inside
ipv6_hop_ioam(). It also updates ip6_parse_tlv() to refresh the network
header pointer ("nh") when returning from ipv6_hop_ioam().
Fixes: 9ee11f0fff20 ("ipv6: ioam: Data plane support for Pre-allocated Trace")
Reported-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
| -rw-r--r-- | net/ipv6/exthdrs.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c index 4952ae792450..02e9ffb63af1 100644 --- a/net/ipv6/exthdrs.c +++ b/net/ipv6/exthdrs.c @@ -177,6 +177,8 @@ static bool ip6_parse_tlv(bool hopbyhop, case IPV6_TLV_IOAM: if (!ipv6_hop_ioam(skb, off)) return false; + + nh = skb_network_header(skb); break; case IPV6_TLV_JUMBO: if (!ipv6_hop_jumbo(skb, off)) @@ -943,6 +945,14 @@ static bool ipv6_hop_ioam(struct sk_buff *skb, int optoff) if (!skb_valid_dst(skb)) ip6_route_input(skb); + /* About to mangle packet header */ + if (skb_ensure_writable(skb, optoff + 2 + hdr->opt_len)) + goto drop; + + /* Trace pointer may have changed */ + trace = (struct ioam6_trace_hdr *)(skb_network_header(skb) + + optoff + sizeof(*hdr)); + ioam6_fill_trace_data(skb, ns, trace, true); break; default: |