projects / ipfire-2.x.git / blame
| Commit | Line | Data |
|---|---|---|
| d54a2ce4 MT |
1 | From ad4a8ff7d9097008d7623df8543df435bfddeac8 Mon Sep 17 00:00:00 2001 |
| 2 | From: Simon Kelley <simon@thekelleys.org.uk> | |
| 3 | Date: Thu, 9 Apr 2015 21:48:00 +0100 | |
| 697b4f04 MT |
4 | Subject: [PATCH 073/113] Fix crash on receipt of certain malformed DNS |
| 5 | requests. | |
| d54a2ce4 MT |
6 | |
| 7 | --- | |
| 8 | CHANGELOG | 3 +++ | |
| 9 | src/rfc1035.c | 9 ++++++--- | |
| 10 | 2 files changed, 9 insertions(+), 3 deletions(-) | |
| 11 | ||
| 12 | diff --git a/CHANGELOG b/CHANGELOG | |
| 13 | index 6aa3d851a297..9af617056f1f 100644 | |
| 14 | --- a/CHANGELOG | |
| 15 | +++ b/CHANGELOG | |
| 16 | @@ -125,6 +125,9 @@ version 2.72 | |
| 17 | Fix problem with --local-service option on big-endian platforms | |
| 18 | Thanks to Richard Genoud for the patch. | |
| 19 | ||
| 20 | + Fix crash on receipt of certain malformed DNS requests. Thanks | |
| 21 | + to Nick Sampanis for spotting the problem. | |
| 22 | + | |
| 23 | ||
| 24 | version 2.71 | |
| 25 | Subtle change to error handling to help DNSSEC validation | |
| 26 | diff --git a/src/rfc1035.c b/src/rfc1035.c | |
| 27 | index 7a07b0cee906..a995ab50d74a 100644 | |
| 28 | --- a/src/rfc1035.c | |
| 29 | +++ b/src/rfc1035.c | |
| 30 | @@ -1198,7 +1198,10 @@ unsigned int extract_request(struct dns_header *header, size_t qlen, char *name, | |
| 31 | size_t setup_reply(struct dns_header *header, size_t qlen, | |
| 32 | struct all_addr *addrp, unsigned int flags, unsigned long ttl) | |
| 33 | { | |
| 34 | - unsigned char *p = skip_questions(header, qlen); | |
| 35 | + unsigned char *p; | |
| 36 | + | |
| 37 | + if (!(p = skip_questions(header, qlen))) | |
| 38 | + return 0; | |
| 39 | ||
| 40 | /* clear authoritative and truncated flags, set QR flag */ | |
| 41 | header->hb3 = (header->hb3 & ~(HB3_AA | HB3_TC)) | HB3_QR; | |
| 42 | @@ -1214,7 +1217,7 @@ size_t setup_reply(struct dns_header *header, size_t qlen, | |
| 43 | SET_RCODE(header, NOERROR); /* empty domain */ | |
| 44 | else if (flags == F_NXDOMAIN) | |
| 45 | SET_RCODE(header, NXDOMAIN); | |
| 46 | - else if (p && flags == F_IPV4) | |
| 47 | + else if (flags == F_IPV4) | |
| 48 | { /* we know the address */ | |
| 49 | SET_RCODE(header, NOERROR); | |
| 50 | header->ancount = htons(1); | |
| 51 | @@ -1222,7 +1225,7 @@ size_t setup_reply(struct dns_header *header, size_t qlen, | |
| 52 | add_resource_record(header, NULL, NULL, sizeof(struct dns_header), &p, ttl, NULL, T_A, C_IN, "4", addrp); | |
| 53 | } | |
| 54 | #ifdef HAVE_IPV6 | |
| 55 | - else if (p && flags == F_IPV6) | |
| 56 | + else if (flags == F_IPV6) | |
| 57 | { | |
| 58 | SET_RCODE(header, NOERROR); | |
| 59 | header->ancount = htons(1); | |
| 60 | -- | |
| 61 | 2.1.0 | |
| 62 |