#!/bin/sh # panic: m_apply, length > size of mbuf chain (8 extra) # cpuid = 1 # time = 1753341719 # KDB: stack backtrace: # db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe01f00c5080 # vpanic() at vpanic+0x136/frame 0xfffffe01f00c51b0 # panic() at panic+0x43/frame 0xfffffe01f00c5210 # m_apply() at m_apply+0x2d3/frame 0xfffffe01f00c5260 # sctp_delayed_cksum() at sctp_delayed_cksum+0x4c/frame 0xfffffe01f00c5290 # ip6_output_delayed_csum() at ip6_output_delayed_csum+0xaa/frame 0xfffffe01f00c52d0 # ip6_output() at ip6_output+0x19e6/frame 0xfffffe01f00c5490 # sctp_lowlevel_chunk_output() at sctp_lowlevel_chunk_output+0x104f/frame 0xfffffe01f00c55d0 # sctp_med_chunk_output() at sctp_med_chunk_output+0x2ad2/frame 0xfffffe01f00c5fb0 # sctp_chunk_output() at sctp_chunk_output+0x121c/frame 0xfffffe01f00c6960 # sctp_lower_sosend() at sctp_lower_sosend+0x146c/frame 0xfffffe01f00c6b50 # sctp_sosend() at sctp_sosend+0x333/frame 0xfffffe01f00c6c70 # sousrsend() at sousrsend+0x79/frame 0xffkern_sendit() at kern_sendit+0x1be/frame 0xfffffe01f00c6d60 # sendit() at sendit+0x1ab/frame 0xfffffe01f00c6db0 # sys_sendto() at sys_sendto+0x4d/frame 0xfffffe01f00c6e00 # amd64_syscall() at amd64_syscall+0x169/frame 0xfffffe01f00c6f30 # fast_syscall_common() at fast_syscall_common+0xf8/frame 0xfffffe01f00c6f30 # --- syscall (0, FreeBSD ELF64, syscall), rip = 0x823035b0a, rsp = 0x8208fa048, rbp = 0x8208fa060 --- # KDB: enter: panic # [ thread pid 41871 tid 736799 ] # Stopped at kdb_enter+0x33: movq $0,0x1231b52(%rip) # db> x/s version # version: FreeBSD 15.0-CURRENT #0 main-n279001-7502c1f27082-dirty: Wed Jul 23 20:31:48 CEST 2025 # pho@mercat1.netperf.freebsd.org:/usr/src/sys/amd64/compile/PHO # db> [ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1 . ../default.cfg set -u prog=$(basename "$0" .sh) cat > /tmp/$prog.c < #include #include #include #include #include #include #include #include #include uint64_t r[1] = {0xffffffffffffffff}; int main(void) { syscall(SYS_mmap, /*addr=*/0x200000000000ul, /*len=*/0x1000000ul, /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x1012ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); const char* reason; (void)reason; intptr_t res = 0; if (write(1, "executing program\n", sizeof("executing program\n") - 1)) { } res = syscall(SYS_socket, /*domain=*/0x1cul, /*type=SOCK_STREAM*/ 1ul, /*proto=*/0x84); if (res != -1) r[0] = res; *(uint8_t*)0x2000000001c0 = 0x10; *(uint8_t*)0x2000000001c1 = 2; *(uint16_t*)0x2000000001c2 = htobe16(0x4e23); *(uint32_t*)0x2000000001c4 = htobe32(0); memset((void*)0x2000000001c8, 0, 8); memset((void*)0x2000000001d0, 0, 112); *(uint32_t*)0x200000000240 = 0; *(uint32_t*)0x200000000244 = 0x5234; *(uint32_t*)0x200000000248 = 0xffff; *(uint32_t*)0x20000000024c = 0x314; *(uint32_t*)0x200000000250 = 0x3bb; *(uint16_t*)0x200000000254 = 2; *(uint8_t*)0x200000000256 = 9; syscall(SYS_setsockopt, /*fd=*/r[0], /*level=*/0x84, /*opt=*/0xa, /*val=*/0x2000000001c0ul, /*len=*/0x98ul); *(uint8_t*)0x200000000000 = 0x1c; *(uint8_t*)0x200000000001 = 0x1c; *(uint16_t*)0x200000000002 = htobe16(0x4e22); *(uint32_t*)0x200000000004 = 0; memset((void*)0x200000000008, 0, 16); *(uint32_t*)0x200000000018 = 0; syscall(SYS_bind, /*fd=*/r[0], /*addr=*/0x200000000000ul, /*addrlen=*/0x1cul); *(uint8_t*)0x200000000180 = 0x5f; *(uint8_t*)0x200000000181 = 0x1c; *(uint16_t*)0x200000000182 = htobe16(0x4e22); *(uint32_t*)0x200000000184 = 0; *(uint64_t*)0x200000000188 = htobe64(0); *(uint64_t*)0x200000000190 = htobe64(1); *(uint32_t*)0x200000000198 = 0; syscall(SYS_connect, /*fd=*/r[0], /*addr=*/0x200000000180ul, /*addrlen=*/0x1cul); memset((void*)0x2000000020c0, 209, 1); syscall(SYS_sendto, /*fd=*/r[0], /*buf=*/0x2000000020c0ul, /*len=*/0xffeful, /*f=MSG_NOSIGNAL|MSG_EOF|MSG_DONTWAIT|MSG_DONTROUTE*/ 0x20184ul, /*addr=*/0ul, /*addrlen=*/0ul); return 0; } EOF mycc -o /tmp/$prog -Wall -Wextra -O0 /tmp/$prog.c || exit 1 work=/tmp/$prog.dir rm -rf $work mkdir $work cd /tmp/$prog.dir kldstat | grep -q sctp && loaded=0 || { kldload sctp.ko && loaded=1; } timeout 3m /tmp/$prog > /dev/null 2>&1 rm -rf /tmp/$prog /tmp/$prog.c /tmp/$prog.core /tmp/$prog.?????? $work [ $loaded -eq 1 ] && kldunload sctp.ko exit 0