From 506ada89629ec7059b96ecfb0dc7d33ece0103ca Mon Sep 17 00:00:00 2001 From: Eduard Zingerman Date: Fri, 4 Sep 2026 17:05:56 -0700 Subject: bpf: mark a NULL kfunc argument precise check_kfunc_arg() allows bpf_register_is_null() for nullable arguments w/o marking the underlying scalar register precise. Hence a checkpoint created on such a path would prune against arbitrary scalar value. Fixes: 3bda08b63670 ("bpf: Allow NULL buffers in bpf_dynptr_slice(_rw)") Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/r/20260904-register-is-null-precise-fixes-v1-5-0f5a360ff15d@gmail.com Signed-off-by: Alexei Starovoitov --- scripts/objdump-func | 45 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) create mode 100755 scripts/objdump-func (limited to 'scripts/objdump-func') diff --git a/scripts/objdump-func b/scripts/objdump-func new file mode 100755 index 000000000..7b15b873d --- /dev/null +++ b/scripts/objdump-func @@ -0,0 +1,45 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# +# Disassemble a single function. +# +# usage: objdump-func [ ...] + +set -o errexit +set -o nounset + +OBJDUMP="${CROSS_COMPILE:-}objdump" + +command -v gawk >/dev/null 2>&1 || die "gawk isn't installed" + +usage() { + echo "usage: objdump-func [ ...]" >&2 + exit 1 +} + +[[ $# -lt 2 ]] && usage + +OBJ=$1; shift +FUNCS=("$@") + +${OBJDUMP} -wdr $OBJ | gawk -M -v _funcs="${FUNCS[*]}" ' + BEGIN { split(_funcs, funcs); } + /^$/ { func_match=0; } + /<.*>:/ { + f = gensub(/.*<(.*)>:/, "\\1", 1); + for (i in funcs) { + # match compiler-added suffixes like ".cold", etc + if (f ~ "^" funcs[i] "(\\..*)?") { + func_match = 1; + base = strtonum("0x" $1); + break; + } + } + } + { + if (func_match) { + addr = strtonum("0x" $1); + printf("%04x ", addr - base); + print; + } + }' -- cgit v1.3.1