From mboxrd@z Thu Jan 1 00:00:00 1970 From: Patrick McHardy Subject: [PATCH 2.6 5/5]: Fix multiple bugs in ip6t_frag.c Date: Thu, 14 Oct 2004 02:19:19 +0200 Sender: netfilter-devel-bounces@lists.netfilter.org Message-ID: <416DC607.9020201@trash.net> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="------------090006050806040902000601" Cc: Netfilter Development Mailinglist Return-path: To: "David S. Miller" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: netfilter-devel-bounces@lists.netfilter.org List-Id: netfilter-devel.vger.kernel.org This is a multi-part message in MIME format. --------------090006050806040902000601 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit This patch fixes another invalid cast and endian issues when using frag_off in ip6t_frag. It also removes some dead code and a useless check. --------------090006050806040902000601 Content-Type: text/x-patch; name="5.diff" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="5.diff" # This is a BitKeeper generated diff -Nru style patch. # # ChangeSet # 2004/10/14 01:06:10+02:00 yasuyuki.kozakai@toshiba.co.jp # [NETFILTER]: Fix multiple bugs in ip6t_frag.c # # The first patch fixes following bugs in ip6t_frag.c, # # - Wrong cast the pointer to extension header. # - header length of Fragment Header is statically 8 octets. # Then the option "--frag-len" doesn't make sense. # - There are endian issues where using frag->info. # - Reserved fields are not 2 bit but 8bit + 2 bit. (see RFC2460) # # Signed-off-by: Yasuyuki KOZAKAI # Signed-off-by: Patrick McHardy # # net/ipv6/netfilter/ip6t_frag.c # 2004/10/14 01:05:45+02:00 yasuyuki.kozakai@toshiba.co.jp +37 -59 # [NETFILTER]: Fix multiple bugs in ip6t_frag.c # # The first patch fixes following bugs in ip6t_frag.c, # # - Wrong cast the pointer to extension header. # - header length of Fragment Header is statically 8 octets. # Then the option "--frag-len" doesn't make sense. # - There are endian issues where using frag->info. # - Reserved fields are not 2 bit but 8bit + 2 bit. (see RFC2460) # # Signed-off-by: Yasuyuki KOZAKAI # Signed-off-by: Patrick McHardy # diff -Nru a/net/ipv6/netfilter/ip6t_frag.c b/net/ipv6/netfilter/ip6t_frag.c --- a/net/ipv6/netfilter/ip6t_frag.c 2004-10-14 01:37:39 +02:00 +++ b/net/ipv6/netfilter/ip6t_frag.c 2004-10-14 01:37:39 +02:00 @@ -14,8 +14,6 @@ #include #include -#include - #include #include @@ -29,29 +27,6 @@ #define DEBUGP(format, args...) #endif -#if 0 -#if BYTE_ORDER == BIG_ENDIAN -#define IP6F_OFF_MASK 0xfff8 /* mask out offset from _offlg */ -#define IP6F_RESERVED_MASK 0x0006 /* reserved bits in ip6f_offlg */ -#define IP6F_MORE_FRAG 0x0001 /* more-fragments flag */ -#else /* BYTE_ORDER == LITTLE_ENDIAN */ -#define IP6F_OFF_MASK 0xf8ff /* mask out offset from _offlg */ -#define IP6F_RESERVED_MASK 0x0600 /* reserved bits in ip6f_offlg */ -#define IP6F_MORE_FRAG 0x0100 /* more-fragments flag */ -#endif -#endif - -#define IP6F_OFF_MASK 0xf8ff /* mask out offset from _offlg */ -#define IP6F_RESERVED_MASK 0x0600 /* reserved bits in ip6f_offlg */ -#define IP6F_MORE_FRAG 0x0100 /* more-fragments flag */ - -struct fraghdr { - __u8 nexthdr; - __u8 hdrlen; - __u16 info; - __u32 id; -}; - /* Returns 1 if the id is matched by the range, 0 otherwise */ static inline int id_match(u_int32_t min, u_int32_t max, u_int32_t id, int invert) @@ -74,7 +49,7 @@ u_int16_t datalen, int *hotdrop) { - struct fraghdr *frag = NULL; + struct frag_hdr *frag = NULL; const struct ip6t_frag *fraginfo = matchinfo; unsigned int temp; int len; @@ -107,7 +82,7 @@ break; } - hdr=(struct ipv6_opt_hdr *)skb->data+ptr; + hdr=(struct ipv6_opt_hdr *)(skb->data+ptr); /* Calculate the header length */ if (nexthdr == NEXTHDR_FRAGMENT) { @@ -150,59 +125,62 @@ /* FRAG header not found */ if ( temp != MASK_FRAGMENT ) return 0; - if (len < (int)sizeof(struct fraghdr)){ + if (len < sizeof(struct frag_hdr)){ *hotdrop = 1; return 0; } - frag = (struct fraghdr *) (skb->data + ptr); + frag = (struct frag_hdr *) (skb->data + ptr); - DEBUGP("IPv6 FRAG LEN %u %u ", hdrlen, frag->hdrlen); - DEBUGP("INFO %04X ", frag->info); - DEBUGP("OFFSET %04X ", frag->info & IP6F_OFF_MASK); - DEBUGP("RES %04X ", frag->info & IP6F_RESERVED_MASK); - DEBUGP("MF %04X ", frag->info & IP6F_MORE_FRAG); - DEBUGP("ID %u %08X\n", ntohl(frag->id), ntohl(frag->id)); + DEBUGP("INFO %04X ", frag->frag_off); + DEBUGP("OFFSET %04X ", ntohs(frag->frag_off) & ~0x7); + DEBUGP("RES %02X %04X", frag->reserved, ntohs(frag->frag_off) & 0x6); + DEBUGP("MF %04X ", frag->frag_off & htons(IP6_MF)); + DEBUGP("ID %u %08X\n", ntohl(frag->identification), + ntohl(frag->identification)); DEBUGP("IPv6 FRAG id %02X ", (id_match(fraginfo->ids[0], fraginfo->ids[1], - ntohl(frag->id), + ntohl(frag->identification), !!(fraginfo->invflags & IP6T_FRAG_INV_IDS)))); - DEBUGP("len %02X %04X %02X ", - fraginfo->hdrlen, hdrlen, - (!fraginfo->hdrlen || - (fraginfo->hdrlen == hdrlen) ^ - !!(fraginfo->invflags & IP6T_FRAG_INV_LEN))); - DEBUGP("res %02X %02X %02X ", - (fraginfo->flags & IP6T_FRAG_RES), frag->info & IP6F_RESERVED_MASK, - !((fraginfo->flags & IP6T_FRAG_RES) && (frag->info & IP6F_RESERVED_MASK))); + DEBUGP("res %02X %02X%04X %02X ", + (fraginfo->flags & IP6T_FRAG_RES), frag->reserved, + ntohs(frag->frag_off) & 0x6, + !((fraginfo->flags & IP6T_FRAG_RES) + && (frag->reserved || (ntohs(frag->frag_off) & 0x6)))); DEBUGP("first %02X %02X %02X ", - (fraginfo->flags & IP6T_FRAG_FST), frag->info & IP6F_OFF_MASK, - !((fraginfo->flags & IP6T_FRAG_FST) && (frag->info & IP6F_OFF_MASK))); + (fraginfo->flags & IP6T_FRAG_FST), + ntohs(frag->frag_off) & ~0x7, + !((fraginfo->flags & IP6T_FRAG_FST) + && (ntohs(frag->frag_off) & ~0x7))); DEBUGP("mf %02X %02X %02X ", - (fraginfo->flags & IP6T_FRAG_MF), frag->info & IP6F_MORE_FRAG, - !((fraginfo->flags & IP6T_FRAG_MF) && !((frag->info & IP6F_MORE_FRAG)))); + (fraginfo->flags & IP6T_FRAG_MF), + ntohs(frag->frag_off) & IP6_MF, + !((fraginfo->flags & IP6T_FRAG_MF) + && !((ntohs(frag->frag_off) & IP6_MF)))); DEBUGP("last %02X %02X %02X\n", - (fraginfo->flags & IP6T_FRAG_NMF), frag->info & IP6F_MORE_FRAG, - !((fraginfo->flags & IP6T_FRAG_NMF) && (frag->info & IP6F_MORE_FRAG))); + (fraginfo->flags & IP6T_FRAG_NMF), + ntohs(frag->frag_off) & IP6_MF, + !((fraginfo->flags & IP6T_FRAG_NMF) + && (ntohs(frag->frag_off) & IP6_MF))); return (frag != NULL) && (id_match(fraginfo->ids[0], fraginfo->ids[1], - ntohl(frag->id), + ntohl(frag->identification), !!(fraginfo->invflags & IP6T_FRAG_INV_IDS))) && - (!fraginfo->hdrlen || - (fraginfo->hdrlen == hdrlen) ^ - !!(fraginfo->invflags & IP6T_FRAG_INV_LEN)) - && - !((fraginfo->flags & IP6T_FRAG_RES) && (frag->info & IP6F_RESERVED_MASK)) + !((fraginfo->flags & IP6T_FRAG_RES) + && (frag->reserved || (ntohs(frag->frag_off) & 0x6))) && - !((fraginfo->flags & IP6T_FRAG_FST) && (frag->info & IP6F_OFF_MASK)) + !((fraginfo->flags & IP6T_FRAG_FST) + && (ntohs(frag->frag_off) & ~0x7)) && - !((fraginfo->flags & IP6T_FRAG_MF) && !((frag->info & IP6F_MORE_FRAG))) + !((fraginfo->flags & IP6T_FRAG_MF) + && !(ntohs(frag->frag_off) & IP6_MF)) && - !((fraginfo->flags & IP6T_FRAG_NMF) && (frag->info & IP6F_MORE_FRAG)); + !((fraginfo->flags & IP6T_FRAG_NMF) + && (ntohs(frag->frag_off) & IP6_MF)); } /* Called when user tries to insert an entry of this type. */ --------------090006050806040902000601--