From 33a154a96e71a34a1bcca9f40da343dbbf7b38b4 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Thu, 1 Oct 2026 14:52:55 +0000 Subject: selftests/bpf: Test packet range of pointers sharing an id Add tests where two packet pointers share an id and tightening one pointer's umax from its var_off would put it less than their constant distance from the other's umax: with an index & 0x38 capped at 50, the base pointer keeps umax 50, so the pointer 8 bytes further on must keep umax 58, even though its known bits allow at most 56. These refused a valid program or accepted an out-of-bounds access before the fix: - check the advanced copy, load through the base: valid, was refused; - check the base, load the byte at base + 1 through a copy advanced by 8: was accepted; - check base + 4, load 4 bytes at base + 2 through base + 8: reads two bytes past the checked range, was accepted; - the same as the second with data_meta pointers checked against data: was accepted. These pass with and without the fix and cover nearby paths: - subtract an unknown scalar from a checked pointer and load below it (the range is kept across a new id); - reach a load through two paths whose checks cover 8 and 7 bytes after the loaded pointer; the second path must not be pruned by the first; - spill a copy of a pointer, check the pointer, fill the copy and load one byte past the checked range: the load is refused, and the copy has the range of the check. Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20261001145255.855630-2-alexei.starovoitov@gmail.com Signed-off-by: Kumar Kartikeya Dwivedi --- scripts/extract-fwblobs | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) create mode 100755 scripts/extract-fwblobs (limited to 'scripts/extract-fwblobs') diff --git a/scripts/extract-fwblobs b/scripts/extract-fwblobs new file mode 100755 index 000000000..53729124e --- /dev/null +++ b/scripts/extract-fwblobs @@ -0,0 +1,30 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# +# ----------------------------------------------------------------------------- +# Extracts the vmlinux built-in firmware blobs - requires a non-stripped image +# ----------------------------------------------------------------------------- + +if [ -z "$1" ]; then + echo "Must provide a non-stripped vmlinux as argument" + exit 1 +fi + +read -r RD_ADDR_HEX RD_OFF_HEX <<< "$( readelf -SW "$1" |\ +grep -w rodata | awk '{print "0x"$5" 0x"$6}' )" + +FW_SYMS="$(readelf -sW "$1" |\ +awk -n '/fw_end/ { end=$2 ; print name " 0x" start " 0x" end; } { start=$2; name=$8; }')" + +while IFS= read -r entry; do + read -r FW_NAME FW_ADDR_ST_HEX FW_ADDR_END_HEX <<< "$entry" + + # Notice kernel prepends _fw_ and appends _bin to the FW name + # in rodata; hence we hereby filter that out. + FW_NAME=${FW_NAME:4:-4} + + FW_OFFSET="$(printf "%d" $((FW_ADDR_ST_HEX - RD_ADDR_HEX + RD_OFF_HEX)))" + FW_SIZE="$(printf "%d" $((FW_ADDR_END_HEX - FW_ADDR_ST_HEX)))" + + dd if="$1" of="./${FW_NAME}" bs="${FW_SIZE}" count=1 iflag=skip_bytes skip="${FW_OFFSET}" +done <<< "${FW_SYMS}" -- cgit v1.3.1