| Message ID | 82e982530f74f7b736071f041918c22919b734d8.1620223174.git.pabeni@redhat.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | udp: more FRAGLIST fixes | expand |
| Context | Check | Description |
|---|---|---|
| netdev/cover_letter | success | Link |
| netdev/fixes_present | success | Link |
| netdev/patch_count | success | Link |
| netdev/tree_selection | success | Clearly marked for net |
| netdev/subject_prefix | success | Link |
| netdev/cc_maintainers | warning | 2 maintainers not CCed: yoshfuji@linux-ipv6.org dsahern@kernel.org |
| netdev/source_inline | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Link |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/build_32bit | success | Errors and warnings before: 7 this patch: 7 |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/verify_fixes | success | Link |
| netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 8 lines checked |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 7 this patch: 7 |
| netdev/header_inline | success | Link |
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 15f5504adf5b..055fceb18bea 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -857,7 +857,7 @@ void udp_set_csum(bool nocheck, struct sk_buff *skb, if (nocheck) { uh->check = 0; - } else if (skb_is_gso(skb)) { + } else if (skb_is_gso(skb) && skb->ip_summed == CHECKSUM_PARTIAL) { uh->check = ~udp_v4_check(len, saddr, daddr, 0); } else if (skb->ip_summed == CHECKSUM_PARTIAL) { uh->check = 0;
In the following scenario: GRO -> SKB_GSO_FRAGLIST aggregation -> forward -> xmit over UDP tunnel SKB_GSO_FRAGLIST packet traverse an UDP tunnel in the xmit path. The tunnel code sets up the outer header csum via udp_set_csum() and the latter assumes that each GSO packet is CHECKSUM_PARTIAL. Since the introduction of SKB_GSO_FRAGLIST and veth GRO, the above assumption is not true anymore as SKB_GSO_FRAGLIST are CHECKSUM_UNNECESSARY, and the csum for the outer header will be left uninitialized. All the above will cause wrong outer UDP header checksum when the mentioned packet will be xmitted on some real NIC. This change addresses the issue explicitly checking for both gso and CHECKSUM_PARTIAL in udp_set_csum(), so that the mentioned packet will be processed correctly. Fixes: 9fd1ff5d2ac7 ("udp: Support UDP fraglist GRO/GSO.") Signed-off-by: Paolo Abeni <pabeni@redhat.com> --- net/ipv4/udp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)