From 556b91a8a758b6ef28fee25bc0dad834d4815b4a Mon Sep 17 00:00:00 2001 From: Francesco Chemolli <5175948+kinkie@users.noreply.github.com> Date: Sat, 30 May 2026 10:16:33 +0000 Subject: [PATCH] Harden peerDigestSwapInMask against invalid cache digest reply (#2423) A cache_digest on-the-wire size may be bigger than the mask_size declared in the digest itself. Ignore the digest in case this happens. --- src/peer_digest.cc | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/src/peer_digest.cc b/src/peer_digest.cc index 00fb8cb4f7..3546208e72 100644 --- a/src/peer_digest.cc +++ b/src/peer_digest.cc @@ -558,6 +558,11 @@ peerDigestSwapInMask(void *data, char *buf, ssize_t size) * NOTENOTENOTENOTENOTE: buf doesn't point to pd->cd->mask anymore! * we need to do the copy ourselves! */ + Assure(size >= 0); + if (fetch->mask_offset + size > static_cast(pd->cd->mask_size)) { + finishAndDeleteFetch(fetch, "peer digest mask data too large", true); + return -1; + } memcpy(pd->cd->mask + fetch->mask_offset, buf, size); /* NOTE! buf points to the middle of pd->cd->mask! */ -- 2.47.3