aljaz/lightning
1
0
Fork 0
mirror of https://github.com/aljazceru/lightning.git synced 2026-01-08 00:24:28 +01:00
Code Issues Packages Projects Releases Wiki Activity

lightningd: don't crash if peer manages to spend onchain HTLC after we've abandoned upstream.

Browse Source 
Since we now abandon HTLCs to avoid breaking a channel (in limited circumstances), the
peer can take the funds if they beat us to spend the HTLC before we timeout.  This is extremely
unusual, but finally happend in CI.

First it fails our internal sanity checks, but then it would fail when we tried to fulfill
an already-failed HTLC:

```
**BROKEN** lightningd: fulfill_our_htlc_out:Output preimage, input failonion?
**BROKEN** lightningd: FATAL SIGNAL 6 (version f82fedb-modded)
**BROKEN** lightningd: backtrace: common/daemon.c:38 (send_backtrace) 0x55c09b04f0b5
**BROKEN** lightningd: backtrace: common/daemon.c:75 (crashdump) 0x55c09b04f247
**BROKEN** lightningd: backtrace: ./signal/../sysdeps/unix/sysv/linux/x86_64/libc_sigaction.c:0 ((null)) 0x7f607463551f
**BROKEN** lightningd: backtrace: ./nptl/pthread_kill.c:44 (__pthread_kill_implementation) 0x7f6074689a7c
**BROKEN** lightningd: backtrace: ./nptl/pthread_kill.c:78 (__pthread_kill_internal) 0x7f6074689a7c
**BROKEN** lightningd: backtrace: ./nptl/pthread_kill.c:89 (__GI___pthread_kill) 0x7f6074689a7c
**BROKEN** lightningd: backtrace: ../sysdeps/posix/raise.c:26 (__GI_raise) 0x7f6074635475
**BROKEN** lightningd: backtrace: ./stdlib/abort.c:79 (__GI_abort) 0x7f607461b7f2
**BROKEN** lightningd: backtrace: lightningd/log.c:1016 (fatal_vfmt) 0x55c09afdb7cb
**BROKEN** lightningd: backtrace: lightningd/log.c:1026 (fatal) 0x55c09afdb880
**BROKEN** lightningd: backtrace: lightningd/htlc_end.c:87 (corrupt) 0x55c09afc9472
**BROKEN** lightningd: backtrace: lightningd/htlc_end.c:207 (htlc_out_check) 0x55c09afc9c6b
**BROKEN** lightningd: backtrace: lightningd/peer_htlcs.c:1451 (fulfill_our_htlc_out) 0x55c09b004dd7
**BROKEN** lightningd: backtrace: lightningd/peer_htlcs.c:1526 (onchain_fulfilled_htlc) 0x55c09b0050fe
**BROKEN** lightningd: backtrace: lightningd/onchain_control.c:313 (handle_extracted_preimage) 0x55c09afdf9f8
**BROKEN** lightningd: backtrace: lightningd/onchain_control.c:1423 (onchain_msg) 0x55c09afe2da9
**BROKEN** lightningd: backtrace: lightningd/subd.c:557 (sd_msg_read) 0x55c09b019ac8
```

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This commit is contained in:
Rusty Russell
2023-07-27 16:42:20 +09:30
parent 5f2072869a
commit c98711ad28
2 changed files with 15 additions and 8 deletions
Download Patch File Download Diff File Expand all files Collapse all files

6
lightningd/htlc_end.c
View File

@@ -203,9 +203,9 @@ struct htlc_out *htlc_out_check(const struct htlc_out *hout,
return corrupt(abortstr,
"Output failmsg, input preimage");
} else if (hout->preimage) {
if (hout->in->failonion)
return corrupt(abortstr,
"Output preimage, input failonion");
/* If we abandoned the HTLC to save the incoming channel,
* (see consider_failing_incoming), hout->in->failonion
* will be set! */
if (hout->in->badonion)
return corrupt(abortstr,
"Output preimage, input badonion");

17
lightningd/peer_htlcs.c
View File

@@ -1464,11 +1464,18 @@ static void fulfill_our_htlc_out(struct channel *channel, struct htlc_out *hout,
if (hout->am_origin)
payment_succeeded(ld, &hout->payment_hash, hout->partid, hout->groupid, preimage);
else if (hout->in) {
fulfill_htlc(hout->in, preimage);
wallet_forwarded_payment_add(ld->wallet, hout->in,
FORWARD_STYLE_TLV,
channel_scid_or_local_alias(hout->key.channel), hout,
FORWARD_SETTLED, 0);
/* Did we abandon the incoming? Oops! */
if (hout->in->failonion) {
/* FIXME: Accounting? */
log_unusual(channel->log, "FUNDS LOSS of %s: peer took funds onchain before we could time out the HTLC, but we abandoned incoming HTLC to save the incoming channel",
fmt_amount_msat(tmpctx, hout->msat));
} else {
fulfill_htlc(hout->in, preimage);
wallet_forwarded_payment_add(ld->wallet, hout->in,
FORWARD_STYLE_TLV,
channel_scid_or_local_alias(hout->key.channel), hout,
FORWARD_SETTLED, 0);
}
}
}