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Tue, 15 Sep 2026 19:16:43 -0000 X-Groupsio-URL: https://lists.openembedded.org/g/openembedded-core/message/245869 NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-31912 Upstream-commit: https://github.com/the-tcpdump-group/libpcap/commit/d3f358d3cffbe1ecb94d5284b3e81f052a0adcb9 Signed-off-by: Jaipaul Cheernam --- .../libpcap/libpcap/02-CVE-2026-31912.patch | 597 ++++++++++++++++++ .../libpcap/libpcap_1.10.6.bb | 1 + 2 files changed, 598 insertions(+) create mode 100644 meta/recipes-connectivity/libpcap/libpcap/02-CVE-2026-31912.patch diff --git a/meta/recipes-connectivity/libpcap/libpcap/02-CVE-2026-31912.patch b/meta/recipes-connectivity/libpcap/libpcap/02-CVE-2026-31912.patch new file mode 100644 index 0000000000..ceae734ff7 --- /dev/null +++ b/meta/recipes-connectivity/libpcap/libpcap/02-CVE-2026-31912.patch @@ -0,0 +1,597 @@ +From 09e04074ddfbca5fa33693c6e2d4f01a74857f65 Mon Sep 17 00:00:00 2001 +From: Denis Ovsienko +Date: Thu, 30 Jul 2026 13:33:55 +0100 +Subject: [PATCH] CVE-2026-31912: Mind the program bounds in + pcap_offline_filter(). + +The current revision of pcapint_filter_with_aux_data() does not know the +number of instructions in the filter program, it assumes the program +counter always remains within the bounds of the provided filter program +and always reaches a return instruction. This holds for programs that +have been generated or validated by libpcap. + +However, this does not necessarily hold for programs that come from an +external source via pcap_offline_filter() or [deprecated] bpf_filter() +and have not been explicitly validated. If the interpreter executes +such a program and advances the program counter beyond the last +instruction, it will be interpreting memory space after the filter +program as BPF instructions, which in the current implementation will +eventually cause either abort() (another commit addresses that) or +SIGSEGV. + +To fix the latter problem, in pcapint_filter_with_aux_data() add a +parameter for the number of instructions in the program and reject the +packet as soon as (or just before) the program counter goes out of +bounds. Update all incoming code paths to specify the length; also in +pcap_offline_filter(3PCAP) make it clear the function now requires the +'bf_len' member to be set correctly and uses it. + +(backported from commit d1209988c74dd9330659898d3b676ee6bbe1c551) + +(cherry picked from commit d3f358d3cffbe1ecb94d5284b3e81f052a0adcb9) + +Upstream-Status: Backport [https://github.com/the-tcpdump-group/libpcap/commit/d3f358d3cffbe1ecb94d5284b3e81f052a0adcb9] +CVE: CVE-2026-31912 + +Notes on backporting to 1.10.6: + - Adjusted the pcapint_filter() call sites in pcap-dag.c, pcap-netmap.c and + pcap-snf.c to the 1.10.6 code base. In 1.10.7 these were already touched by + the unrelated "low snaplen" fixes (commits d5192db3, fb87fdeb, b0caefe8), + which are not part of this CVE and are not backported here; only the new + bf_len argument is added to each call. + - In bpf_filter.c the scratch-memory-store zero-initialisation and the removal + of the stray BPF_S_ANC_* enum (1.10.7-only cleanups) are not present in + 1.10.6, so only the new pc0 declaration and bounds checks from this commit + are added. + - The upstream CHANGES/changelog hunk is not backported. + +Signed-off-by: Jaipaul Cheernam +--- +diff --git a/bpf_filter.c b/bpf_filter.c +index 510dbd9c..4f9adeea 100644 +--- a/bpf_filter.c ++++ b/bpf_filter.c +@@ -70,6 +70,24 @@ enum { + BPF_S_ANC_VLAN_TAG_PRESENT, + }; + ++/* ++ * Kernel BPF implementations tend to define BPF_MAXINSNS to 512 or 4096, the ++ * userland interpreter in libpcap is meant to support much longer filter ++ * programs. In the latter case it is important that BPF_MAXINSNS does not ++ * interfere with the safety checks in the validator and the interpreter: ++ * (BPF_MAXINSNS + UINT8_MAX) * sizeof(struct bpf_insn) < UINT32_MAX ++ * It makes the most sense to be able to interpret as many instructions as ++ * pcap_compile() can produce, without optimization, for a valid filter ++ * expression before it consumes as much memory as the current definitions of ++ * NCHUNKS and CHUNKSIZE() allow. For some expressions this can be almost ++ * 1.53 million instructions on a 64-bit machine and twice as many on a 32-bit ++ * machine. ++ */ ++#ifdef BPF_MAXINSNS ++#undef BPF_MAXINSNS ++#endif ++#define BPF_MAXINSNS 3060000U ++ + /* + * Execute the filter program starting at pc on the packet p + * wirelen is the length of the original packet +@@ -84,12 +102,14 @@ enum { + */ + #if defined(SKF_AD_VLAN_TAG_PRESENT) + u_int +-pcapint_filter_with_aux_data(const struct bpf_insn *pc, const u_char *p, +- u_int wirelen, u_int buflen, const struct pcap_bpf_aux_data *aux_data) ++pcapint_filter_with_aux_data(const struct bpf_insn *pc, const u_int proglen, ++ const u_char *p, const u_int wirelen, const u_int buflen, ++ const struct pcap_bpf_aux_data *aux_data) + #else + u_int +-pcapint_filter_with_aux_data(const struct bpf_insn *pc, const u_char *p, +- u_int wirelen, u_int buflen, const struct pcap_bpf_aux_data *aux_data _U_) ++pcapint_filter_with_aux_data(const struct bpf_insn *pc, const u_int proglen, ++ const u_char *p, const u_int wirelen, const u_int buflen, ++ const struct pcap_bpf_aux_data *aux_data _U_) + #endif + { + register uint32_t A, X; +@@ -99,13 +119,36 @@ pcapint_filter_with_aux_data(const struct bpf_insn *pc, const u_char *p, + if (pc == 0) + /* + * No filter means accept all. ++ * In this case the value of 'proglen' is irrelevant. + */ + return (u_int)-1; ++ if (proglen < 1 || proglen > BPF_MAXINSNS) ++ return 0; ++ ++ /* ++ * Require the current instruction pointer not to overflow for both the ++ * filter program (where the pointer will be dereferenced) and an ++ * immediately following margin (where it will be not). So long as the ++ * margin is large enough to represent the destination of any single ++ * conditional [forward] jump from within the filter program, a single ++ * guard prevents all filter program over-read attempts that result ++ * from the program running out of instructions before a BPF_RET or a ++ * conditional jump directing the interpreter beyond the program end. ++ * Unconditional jumps mean a larger problem space, which the BPF_JA ++ * case below addresses separately. ++ */ ++ const struct bpf_insn *pcend = pc + proglen; ++ if (pcend + UINT8_MAX < pc) ++ return 0; ++ + A = 0; + X = 0; ++ const struct bpf_insn *pc0 = pc; + --pc; + for (;;) { + ++pc; ++ if (pc >= pcend) ++ return 0; + switch (pc->code) { + + default: +@@ -241,6 +284,40 @@ DIAG_ON_DEFAULT_ONLY_SWITCH + continue; + + case BPF_JMP|BPF_JA: ++ /* ++ * The pointer (pc) decrements and increments in units ++ * of sizeof(struct bpf_insn) == 8 bytes. The number ++ * of units is in the [INT32_MIN, INT32_MAX] interval, ++ * hence the result can point before the beginning or ++ * beyond the end of the filter program and can under- ++ * or overflow; also on 32-bit architectures it can ++ * under- or overflow more than once and can test ++ * negative for underflow, overflow and out-of-range ++ * conditions after under- or overflowing at least ++ * once. ++ * ++ * However, it has been verified above that the program ++ * length is sufficiently small and the pointer does ++ * not wrap within the bounds of the filter program, so ++ * there is a one-to-one correspondence between BPF ++ * program counter values [0, proglen) and all valid ++ * values of the pointer. In other words, after this ++ * unconditional jump the pointer arithmetic result ++ * will be valid iff BPF program counter value will be ++ * valid. For the latter problem the solution is ++ * almost the same as in the validator. ++ * ++ * The main difference is that here the current value ++ * of BPF program counter is not a 32-bit unsigned ++ * variable, but a ptrdiff_t expression, which is ++ * 64-bit signed on 64-bit architectures and 32-bit ++ * signed on 32-bit architectures. However, the cast ++ * to 32-bit unsigned is safe in both cases because: ++ * pc0 <= pc < pc0 + proglen, therefore: ++ * 0 <= pc - pc0 < proglen <= BPF_MAXINSNS < INT32_MAX ++ */ ++ if ((bpf_u_int32)(pc - pc0) + 1 + pc->k >= proglen) ++ return 0; + /* + * XXX - we currently implement "ip6 protochain" + * with backward jumps, so sign-extend pc->k. +@@ -394,10 +471,10 @@ DIAG_ON_DEFAULT_ONLY_SWITCH + } + + u_int +-pcapint_filter(const struct bpf_insn *pc, const u_char *p, u_int wirelen, +- u_int buflen) ++pcapint_filter(const struct bpf_insn *pc, const u_int proglen, const u_char *p, ++ u_int wirelen, u_int buflen) + { +- return pcapint_filter_with_aux_data(pc, p, wirelen, buflen, NULL); ++ return pcapint_filter_with_aux_data(pc, proglen, p, wirelen, buflen, NULL); + } + + /* +@@ -417,7 +494,7 @@ pcapint_validate_filter(const struct bpf_insn *f, int len) + u_int i, from; + const struct bpf_insn *p; + +- if (len < 1) ++ if (len < 1 || (u_int)len > BPF_MAXINSNS || f + len < f) + return 0; + + for (i = 0; i < (u_int)len; ++i) { +@@ -483,33 +560,45 @@ pcapint_validate_filter(const struct bpf_insn *f, int len) + case BPF_JMP: + /* + * Check that jumps are within the code block, +- * and that unconditional branches don't go +- * backwards as a result of an overflow. ++ * regardless of the direction. libpcap uses ++ * backward jumps to implement the "protochain" ++ * primitive. All offsets that mean a backward ++ * jump in libpcap (whether in-range or not) in ++ * kernel BPF implementations mean out-of-range ++ * or overflow forward jumps -- kernel ++ * implementations must reject that. ++ * + * Unconditional branches have a 32-bit offset, + * so they could overflow; we check to make + * sure they don't. Conditional branches have + * an 8-bit offset, and the from address is <= +- * BPF_MAXINSNS, and we assume that BPF_MAXINSNS ++ * BPF_MAXINSNS, and we know that BPF_MAXINSNS + * is sufficiently small that adding 255 to it + * won't overflow. + * + * We know that len is <= BPF_MAXINSNS, and we +- * assume that BPF_MAXINSNS is < the maximum size ++ * know that BPF_MAXINSNS is < the maximum value + * of a u_int, so that i + 1 doesn't overflow. +- * +- * For userland, we don't know that the from +- * or len are <= BPF_MAXINSNS, but we know that +- * from <= len, and, except on a 64-bit system, +- * it's unlikely that len, if it truly reflects +- * the size of the program we've been handed, +- * will be anywhere near the maximum size of +- * a u_int. We also don't check for backward +- * branches, as we currently support them in +- * userland for the protochain operation. + */ + from = i + 1; + switch (BPF_OP(p->code)) { + case BPF_JA: ++ /* ++ * So long as both 'from' and bpf_insn.k are ++ * 32-bit unsigned, this check rejects any jump ++ * offset that points outside of the valid BPF ++ * address space of the filter program no ++ * matter whether signed interpretation of the ++ * offset is positive or negative. ++ * ++ * Note that this condition is necessary, but ++ * not sufficient to get correct results from ++ * respective pointer arithmetic in the process ++ * address space. Other necessary conditions ++ * are that BPF_MAXINSNS is correctly defined ++ * and enforced, and that the pointer does not ++ * overflow. ++ */ + if (from + p->k >= (u_int)len) + return 0; + break; +@@ -537,12 +626,14 @@ pcapint_validate_filter(const struct bpf_insn *f, int len) + + /* + * Exported because older versions of libpcap exported them. ++ * This function is deprecated and unsafe, use pcap_offline_filter() instead. + */ + u_int + bpf_filter(const struct bpf_insn *pc, const u_char *p, u_int wirelen, + u_int buflen) + { +- return pcapint_filter(pc, p, wirelen, buflen); ++ // The actual length of the filter program is not known. ++ return pcapint_filter(pc, BPF_MAXINSNS, p, wirelen, buflen); + } + + int +diff --git a/dlpisubs.c b/dlpisubs.c +index d4310de5..19934059 100644 +--- a/dlpisubs.c ++++ b/dlpisubs.c +@@ -203,7 +203,8 @@ pcap_process_pkts(pcap_t *p, pcap_handler callback, u_char *user, + bufp += caplen; + #endif + ++pd->stat.ps_recv; +- if (pcapint_filter(p->fcode.bf_insns, pk, origlen, caplen)) { ++ if (pcapint_filter(p->fcode.bf_insns, p->fcode.bf_len, ++ pk, origlen, caplen)) { + #ifdef HAVE_SYS_BUFMOD_H + pkthdr.ts.tv_sec = sbp->sbh_timestamp.tv_sec; + pkthdr.ts.tv_usec = sbp->sbh_timestamp.tv_usec; +diff --git a/pcap-bpf.c b/pcap-bpf.c +index 49bb273d..13f83930 100644 +--- a/pcap-bpf.c ++++ b/pcap-bpf.c +@@ -1372,7 +1372,8 @@ pcap_read_bpf(pcap_t *p, int cnt, pcap_handler callback, u_char *user) + #endif + */ + if (pb->filtering_in_kernel || +- pcapint_filter(p->fcode.bf_insns, datap, bhp->bh_datalen, caplen)) { ++ pcapint_filter(p->fcode.bf_insns, p->fcode.bf_len, ++ datap, bhp->bh_datalen, caplen)) { + struct pcap_pkthdr pkthdr; + #ifdef BIOCSTSTAMP + struct bintime bt; +diff --git a/pcap-bt-linux.c b/pcap-bt-linux.c +index 2fc51665..9f464e70 100644 +--- a/pcap-bt-linux.c ++++ b/pcap-bt-linux.c +@@ -396,7 +396,8 @@ DIAG_ON_SIGN_COMPARE + pkth.caplen+=sizeof(pcap_bluetooth_h4_header); + pkth.len = pkth.caplen; + if (handle->fcode.bf_insns == NULL || +- pcapint_filter(handle->fcode.bf_insns, pktd, pkth.len, pkth.caplen)) { ++ pcapint_filter(handle->fcode.bf_insns, handle->fcode.bf_len, ++ pktd, pkth.len, pkth.caplen)) { + callback(user, &pkth, pktd); + return 1; + } +diff --git a/pcap-bt-monitor-linux.c b/pcap-bt-monitor-linux.c +index dfba8051..cfe52498 100644 +--- a/pcap-bt-monitor-linux.c ++++ b/pcap-bt-monitor-linux.c +@@ -153,7 +153,8 @@ DIAG_ON_SIGN_COMPARE + bthdr->opcode = htons(hdr.opcode); + + if (handle->fcode.bf_insns == NULL || +- pcapint_filter(handle->fcode.bf_insns, pktd, pkth.len, pkth.caplen)) { ++ pcapint_filter(handle->fcode.bf_insns, handle->fcode.bf_len, ++ pktd, pkth.len, pkth.caplen)) { + callback(user, &pkth, pktd); + return 1; + } +diff --git a/pcap-dag.c b/pcap-dag.c +index 5ce15dd5..334a970c 100644 +--- a/pcap-dag.c ++++ b/pcap-dag.c +@@ -666,7 +666,9 @@ dag_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user) + caplen = p->snapshot; + + /* Run the packet filter if there is one. */ +- if ((p->fcode.bf_insns == NULL) || pcapint_filter(p->fcode.bf_insns, dp, packet_len, caplen)) { ++ if ((p->fcode.bf_insns == NULL) || ++ pcapint_filter(p->fcode.bf_insns, p->fcode.bf_len, ++ dp, packet_len, caplen)) { + + /* convert between timestamp formats */ + register unsigned long long ts; +diff --git a/pcap-dbus.c b/pcap-dbus.c +index d29fb81d..b0f30f6f 100644 +--- a/pcap-dbus.c ++++ b/pcap-dbus.c +@@ -90,7 +90,8 @@ dbus_read(pcap_t *handle, int max_packets _U_, pcap_handler callback, u_char *us + + gettimeofday(&pkth.ts, NULL); + if (handle->fcode.bf_insns == NULL || +- pcapint_filter(handle->fcode.bf_insns, (u_char *)raw_msg, pkth.len, pkth.caplen)) { ++ pcapint_filter(handle->fcode.bf_insns, handle->fcode.bf_len, ++ (u_char *)raw_msg, pkth.len, pkth.caplen)) { + handlep->packets_read++; + callback(user, &pkth, (u_char *)raw_msg); + count++; +diff --git a/pcap-dpdk.c b/pcap-dpdk.c +index c78724e5..4fb8ffea 100644 +--- a/pcap-dpdk.c ++++ b/pcap-dpdk.c +@@ -405,7 +405,9 @@ static int pcap_dpdk_dispatch(pcap_t *p, int max_cnt, pcap_handler cb, u_char *c + + } + if (bp){ +- if (p->fcode.bf_insns==NULL || pcapint_filter(p->fcode.bf_insns, bp, pcap_header.len, pcap_header.caplen)){ ++ if (p->fcode.bf_insns==NULL || ++ pcapint_filter(p->fcode.bf_insns, p->fcode.bf_len, ++ bp, pcap_header.len, pcap_header.caplen)){ + cb(cb_arg, &pcap_header, bp); + }else{ + pd->bpf_drop++; +diff --git a/pcap-haiku.c b/pcap-haiku.c +index 609f585a..7b994fee 100644 +--- a/pcap-haiku.c ++++ b/pcap-haiku.c +@@ -112,8 +112,8 @@ pcap_read_haiku(pcap_t* handle, int maxPackets _U_, pcap_handler callback, + if (handle->fcode.bf_insns) { + // NB: pcapint_filter() takes the wire length and the captured + // length, not the snapshot length of the pcap_t handle. +- if (pcapint_filter(handle->fcode.bf_insns, buffer, wireLength, +- captureLength) == 0) ++ if (pcapint_filter(handle->fcode.bf_insns, handle->fcode.bf_len, ++ buffer, wireLength, captureLength) == 0) + goto drop; + } + +diff --git a/pcap-int.h b/pcap-int.h +index ce0ac698..3d466946 100644 +--- a/pcap-int.h ++++ b/pcap-int.h +@@ -579,13 +579,15 @@ struct pcap_bpf_aux_data { + * Filtering routine that takes the auxiliary data as an additional + * argument. + */ +-u_int pcapint_filter_with_aux_data(const struct bpf_insn *, +- const u_char *, u_int, u_int, const struct pcap_bpf_aux_data *); ++u_int pcapint_filter_with_aux_data(const struct bpf_insn *, const u_int, ++ const u_char *, const u_int, const u_int, ++ const struct pcap_bpf_aux_data *); + + /* + * Filtering routine that doesn't. + */ +-u_int pcapint_filter(const struct bpf_insn *, const u_char *, u_int, u_int); ++u_int pcapint_filter(const struct bpf_insn *, const u_int, const u_char *, ++ u_int, u_int); + + /* + * Routine to validate a BPF program. +diff --git a/pcap-linux.c b/pcap-linux.c +index 20802e43..7e04a041 100644 +--- a/pcap-linux.c ++++ b/pcap-linux.c +@@ -4279,6 +4279,7 @@ static int pcap_handle_packet_mmap( + aux_data.vlan_tag = tp_vlan_tci & 0x0fff; + + if (pcapint_filter_with_aux_data(handle->fcode.bf_insns, ++ handle->fcode.bf_len, + bp, + tp_len, + snaplen, +diff --git a/pcap-netfilter-linux.c b/pcap-netfilter-linux.c +index 344bae47..ade53ea6 100644 +--- a/pcap-netfilter-linux.c ++++ b/pcap-netfilter-linux.c +@@ -257,8 +257,8 @@ netfilter_read_linux(pcap_t *handle, int max_packets, pcap_handler callback, u_c + + gettimeofday(&pkth.ts, NULL); + if (handle->fcode.bf_insns == NULL || +- pcapint_filter(handle->fcode.bf_insns, payload, pkth.len, pkth.caplen)) +- { ++ pcapint_filter(handle->fcode.bf_insns, handle->fcode.bf_len, ++ payload, pkth.len, pkth.caplen)) { + handlep->packets_read++; + callback(user, &pkth, payload); + count++; +diff --git a/pcap-netmap.c b/pcap-netmap.c +index f17f36ca..925f677f 100644 +--- a/pcap-netmap.c ++++ b/pcap-netmap.c +@@ -79,7 +79,8 @@ pcap_netmap_filter(u_char *arg, struct pcap_pkthdr *h, const u_char *buf) + const struct bpf_insn *pc = p->fcode.bf_insns; + + ++pn->rx_pkts; +- if (pc == NULL || pcapint_filter(pc, buf, h->len, h->caplen)) ++ if (pc == NULL || ++ pcapint_filter(pc, p->fcode.bf_len, buf, h->len, h->caplen)) + pn->cb(pn->cb_arg, h, buf); + } + +diff --git a/pcap-npf.c b/pcap-npf.c +index f638bd80..38e985bd 100644 +--- a/pcap-npf.c ++++ b/pcap-npf.c +@@ -720,7 +720,8 @@ pcap_read_npf(pcap_t *p, int cnt, pcap_handler callback, u_char *user) + */ + if (pw->filtering_in_kernel || + p->fcode.bf_insns == NULL || +- pcapint_filter(p->fcode.bf_insns, datap, bhp->bh_datalen, caplen)) { ++ pcapint_filter(p->fcode.bf_insns, p->fcode.bf_len, ++ datap, bhp->bh_datalen, caplen)) { + #ifdef ENABLE_REMOTE + switch (p->rmt_samp.method) { + +diff --git a/pcap-rdmasniff.c b/pcap-rdmasniff.c +index fd6d6fa6..5f15d4c5 100644 +--- a/pcap-rdmasniff.c ++++ b/pcap-rdmasniff.c +@@ -170,7 +170,8 @@ rdmasniff_read(pcap_t *handle, int max_packets, pcap_handler callback, u_char *u + pktd = (u_char *) handle->buffer + wc.wr_id * RDMASNIFF_RECEIVE_SIZE; + + if (handle->fcode.bf_insns == NULL || +- pcapint_filter(handle->fcode.bf_insns, pktd, pkth.len, pkth.caplen)) { ++ pcapint_filter(handle->fcode.bf_insns, handle->fcode.bf_len, ++ pktd, pkth.len, pkth.caplen)) { + callback(user, &pkth, pktd); + ++priv->packets_recv; + ++count; +diff --git a/pcap-snf.c b/pcap-snf.c +index d08275ac..8a57eadd 100644 +--- a/pcap-snf.c ++++ b/pcap-snf.c +@@ -190,7 +190,8 @@ snf_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user) + caplen = p->snapshot; + + if ((p->fcode.bf_insns == NULL) || +- pcapint_filter(p->fcode.bf_insns, req.pkt_addr, req.length, caplen)) { ++ pcapint_filter(p->fcode.bf_insns, p->fcode.bf_len, ++ req.pkt_addr, req.length, caplen)) { + hdr.ts = snf_timestamp_to_timeval(req.timestamp, p->opt.tstamp_precision); + hdr.caplen = caplen; + hdr.len = req.length; +diff --git a/pcap-usb-linux.c b/pcap-usb-linux.c +index bc39b1db..d219721a 100644 +--- a/pcap-usb-linux.c ++++ b/pcap-usb-linux.c +@@ -733,8 +733,8 @@ usb_read_linux_bin(pcap_t *handle, int max_packets _U_, pcap_handler callback, u + pkth.ts.tv_usec = info.hdr->ts_usec; + + if (handle->fcode.bf_insns == NULL || +- pcapint_filter(handle->fcode.bf_insns, handle->buffer, +- pkth.len, pkth.caplen)) { ++ pcapint_filter(handle->fcode.bf_insns, handle->fcode.bf_len, ++ handle->buffer, pkth.len, pkth.caplen)) { + handlep->packets_read++; + callback(user, &pkth, handle->buffer); + return 1; +@@ -921,8 +921,8 @@ usb_read_linux_mmap(pcap_t *handle, int max_packets, pcap_handler callback, u_ch + pkth.ts.tv_usec = hdr->ts_usec; + + if (handle->fcode.bf_insns == NULL || +- pcapint_filter(handle->fcode.bf_insns, (u_char*) hdr, +- pkth.len, pkth.caplen)) { ++ pcapint_filter(handle->fcode.bf_insns, handle->fcode.bf_len, ++ (u_char*) hdr, pkth.len, pkth.caplen)) { + handlep->packets_read++; + callback(user, &pkth, (u_char*) hdr); + packets++; +diff --git a/pcap.c b/pcap.c +index a076c5fb..6caa052b 100644 +--- a/pcap.c ++++ b/pcap.c +@@ -4349,7 +4349,7 @@ pcap_offline_filter(const struct bpf_program *fp, const struct pcap_pkthdr *h, + const struct bpf_insn *fcode = fp->bf_insns; + + if (fcode != NULL) +- return (pcapint_filter(fcode, pkt, h->len, h->caplen)); ++ return (pcapint_filter(fcode, fp->bf_len, pkt, h->len, h->caplen)); + else + return (0); + } +diff --git a/pcap_offline_filter.3pcap b/pcap_offline_filter.3pcap +index 94b9a719..c6d62dee 100644 +--- a/pcap_offline_filter.3pcap ++++ b/pcap_offline_filter.3pcap +@@ -17,7 +17,7 @@ + .\" WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF + .\" MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. + .\" +-.TH PCAP_OFFLINE_FILTER 3PCAP "7 April 2014" ++.TH PCAP_OFFLINE_FILTER 3PCAP "12 March 2026" + .SH NAME + pcap_offline_filter \- check whether a filter matches a packet + .SH SYNOPSIS +@@ -45,10 +45,35 @@ points to the + structure for the packet, and + .I pkt + points to the data in the packet. ++.PP ++In the ++.B \%bpf_program ++structure the ++.B \%bf_insns ++member is either ++.B NULL ++(which means to reject all packets) or points to an array of one or more ++.B \%struct bpf_insn ++elements, in which case the ++.B \%bf_len ++member must be set to the number of elements (this is what ++.BR \%pcap_compile () ++produces). ++.PP ++The filter program must have been compiled for a link-layer header type ++that matches the packet data; also on Linux the filter must not use ++BPF extensions, see ++.BR \%pcap_compile () ++for more information. + .SH RETURN VALUE + .BR pcap_offline_filter () + returns the return value of the filter program. This will be zero if + the packet doesn't match the filter and non-zero if the packet matches + the filter. ++.SH BACKWARD COMPATIBILITY ++.PP ++In libpcap releases before 1.10.7 this function ignored the provided ++.B \%bf_len ++value. + .SH SEE ALSO + .BR pcap (3PCAP) +diff --git a/savefile.c b/savefile.c +index c711a81c..49ef52b6 100644 +--- a/savefile.c ++++ b/savefile.c +@@ -685,7 +685,8 @@ pcapint_offline_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user) + * and, if it passes, process it. + */ + if ((fcode = p->fcode.bf_insns) == NULL || +- pcapint_filter(fcode, data, h.len, h.caplen)) { ++ pcapint_filter(fcode, p->fcode.bf_len, ++ data, h.len, h.caplen)) { + (*callback)(user, &h, data); + n++; /* count the packet */ + if (n >= cnt) diff --git a/meta/recipes-connectivity/libpcap/libpcap_1.10.6.bb b/meta/recipes-connectivity/libpcap/libpcap_1.10.6.bb index 265c46e3bd..aa5265a54c 100644 --- a/meta/recipes-connectivity/libpcap/libpcap_1.10.6.bb +++ b/meta/recipes-connectivity/libpcap/libpcap_1.10.6.bb @@ -13,6 +13,7 @@ DEPENDS = "flex-native bison-native" SRC_URI = "https://www.tcpdump.org/release/${BP}.tar.xz \ file://0001-Fix-error-messages-about-32-bit-integer-overflow.patch \ file://01-CVE-2026-0799.patch \ + file://02-CVE-2026-31912.patch \ " SRC_URI[sha256sum] = "ec97d1206bdd19cb6bdd043eaa9f0037aa732262ec68e070fd7c7b5f834d5dfc"