From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4724244C51F; Thu, 30 Jul 2026 15:29:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785425382; cv=none; b=elZ1wxM/0AnHySLmn1SChCdkmsXIIp5wghWvtDkbtgJLePkmQ+hWzbdpWawQ/ZxfbzoIfq2V2NN8b31Nms/SRYS37hfhYKhsL2R2iL9FjVtxVZo2Lw2mvxluhBwsp1lU53yzNIc7d50C79UEzrmRSXxR8QD6l3/885q7hyjpZHY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785425382; c=relaxed/simple; bh=H1KKWlxXU/ZjVm0MNAAUKrQnccUuHc8s1fzL9DwsLLI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=iDVeP0JrPFNW3RJ5WJO25yV5y8NfITz9m+sPXR6MGgrre1R/fKsz9wkMKbQ9nHcA2JaTdWJ9opDg5WqIFWr5+XsLcqy1n0NTazX34Lq+Tmeiqr7pGRQ2bXLIIro5w+01mv31vUhIKAfCXWgG33oLli4wK4uDsg3gm/HGEZUhdKE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=jHk+bnRf; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="jHk+bnRf" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 97D6B1F000E9; Thu, 30 Jul 2026 15:29:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1785425378; bh=6m18tg3oW2HaixSoQYq6Wd6YJWJgpNFMUGvU6SC6gtg=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=jHk+bnRfQ+HJpY708g7wPqvZyeiaMsdJkF6jmbJslfN5WhgbfeVDSHG7xrmaZOyGi lktfGuyNX6MrbAlTIfR+0IGg5xZajZFrUfwI3qnKbJE++MXJ4y8utFeroRh7vBg19/ +jBiQ5SQBoYZaEfNNGjpcFBFjWAow0pgzupscKXY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Daniel Borkmann , Alexei Starovoitov , Philo Lu , Sasha Levin Subject: [PATCH 6.12 005/602] selftests/bpf: Add tests for ld_{abs,ind} failure path in subprogs Date: Thu, 30 Jul 2026 16:06:37 +0200 Message-ID: <20260730141436.104025736@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260730141435.976815864@linuxfoundation.org> References: <20260730141435.976815864@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Daniel Borkmann commit e0fcb42bc6f41bab2895757d6610616b3820eff7 upstream. Extend the verifier_ld_ind BPF selftests with subprogs containing ld_{abs,ind} and craft the test in a way where the invalid register read is rejected in the fixed case. Also add a success case each, and add additional coverage related to the BTF return type enforcement. # LDLIBS=-static PKG_CONFIG='pkg-config --static' ./vmtest.sh -- ./test_progs -t verifier_ld_ind [...] #611/1 verifier_ld_ind/ld_ind: check calling conv, r1:OK #611/2 verifier_ld_ind/ld_ind: check calling conv, r1 @unpriv:OK #611/3 verifier_ld_ind/ld_ind: check calling conv, r2:OK #611/4 verifier_ld_ind/ld_ind: check calling conv, r2 @unpriv:OK #611/5 verifier_ld_ind/ld_ind: check calling conv, r3:OK #611/6 verifier_ld_ind/ld_ind: check calling conv, r3 @unpriv:OK #611/7 verifier_ld_ind/ld_ind: check calling conv, r4:OK #611/8 verifier_ld_ind/ld_ind: check calling conv, r4 @unpriv:OK #611/9 verifier_ld_ind/ld_ind: check calling conv, r5:OK #611/10 verifier_ld_ind/ld_ind: check calling conv, r5 @unpriv:OK #611/11 verifier_ld_ind/ld_ind: check calling conv, r7:OK #611/12 verifier_ld_ind/ld_ind: check calling conv, r7 @unpriv:OK #611/13 verifier_ld_ind/ld_abs: subprog early exit on ld_abs failure:OK #611/14 verifier_ld_ind/ld_ind: subprog early exit on ld_ind failure:OK #611/15 verifier_ld_ind/ld_abs: subprog with both paths safe:OK #611/16 verifier_ld_ind/ld_ind: subprog with both paths safe:OK #611/17 verifier_ld_ind/ld_abs: reject void return subprog:OK #611/18 verifier_ld_ind/ld_ind: reject void return subprog:OK #611 verifier_ld_ind:OK Summary: 1/18 PASSED, 0 SKIPPED, 0 FAILED Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/r/20260408191242.526279-4-daniel@iogearbox.net Signed-off-by: Alexei Starovoitov Signed-off-by: Philo Lu Signed-off-by: Sasha Levin --- .../selftests/bpf/progs/verifier_ld_ind.c | 142 ++++++++++++++++++ 1 file changed, 142 insertions(+) diff --git a/tools/testing/selftests/bpf/progs/verifier_ld_ind.c b/tools/testing/selftests/bpf/progs/verifier_ld_ind.c index c925ba9a2e74c2..09e81b99eecb4e 100644 --- a/tools/testing/selftests/bpf/progs/verifier_ld_ind.c +++ b/tools/testing/selftests/bpf/progs/verifier_ld_ind.c @@ -107,4 +107,146 @@ __naked void ind_check_calling_conv_r7(void) : __clobber_all); } +/* + * ld_{abs,ind} subprog that always sets r0=1 on the success path. + * bpf_gen_ld_abs() emits a hidden exit with r0=0 when the load helper + * fails. The verifier must model this failure return so that callers + * account for r0=0 as a possible return value. + */ +__naked __noinline __used +static int ldabs_subprog(void) +{ + asm volatile ( + "r6 = r1;" + ".8byte %[ld_abs];" + "r0 = 1;" + "exit;" + : + : __imm_insn(ld_abs, BPF_LD_ABS(BPF_W, 0)) + : __clobber_all); +} + +__naked __noinline __used +static int ldind_subprog(void) +{ + asm volatile ( + "r6 = r1;" + "r7 = 0;" + ".8byte %[ld_ind];" + "r0 = 1;" + "exit;" + : + : __imm_insn(ld_ind, BPF_LD_IND(BPF_W, BPF_REG_7, 0)) + : __clobber_all); +} + +SEC("socket") +__description("ld_abs: subprog early exit on ld_abs failure") +__failure __msg("R9 !read_ok") +__naked void ld_abs_subprog_early_exit(void) +{ + asm volatile ( + "call ldabs_subprog;" + "if r0 != 0 goto l_exit_%=;" + "r0 = r9;" + "l_exit_%=:" + "r0 = 0;" + "exit;" + ::: __clobber_all); +} + +SEC("socket") +__description("ld_ind: subprog early exit on ld_ind failure") +__failure __msg("R9 !read_ok") +__naked void ld_ind_subprog_early_exit(void) +{ + asm volatile ( + "call ldind_subprog;" + "if r0 != 0 goto l_exit_%=;" + "r0 = r9;" + "l_exit_%=:" + "r0 = 0;" + "exit;" + ::: __clobber_all); +} + +SEC("socket") +__description("ld_abs: subprog with both paths safe") +__success +__naked void ld_abs_subprog_both_paths_safe(void) +{ + asm volatile ( + "call ldabs_subprog;" + "r0 = 0;" + "exit;" + ::: __clobber_all); +} + +SEC("socket") +__description("ld_ind: subprog with both paths safe") +__success +__naked void ld_ind_subprog_both_paths_safe(void) +{ + asm volatile ( + "call ldind_subprog;" + "r0 = 0;" + "exit;" + ::: __clobber_all); +} + +/* + * ld_{abs,ind} in subprogs require scalar (int) return type in BTF. + * A test with void return must be rejected. + */ +__naked __noinline __used +static void ldabs_void_subprog(void) +{ + asm volatile ( + "r6 = r1;" + ".8byte %[ld_abs];" + "r0 = 1;" + "exit;" + : + : __imm_insn(ld_abs, BPF_LD_ABS(BPF_W, 0)) + : __clobber_all); +} + +SEC("socket") +__description("ld_abs: reject void return subprog") +__failure __msg("LD_ABS is only allowed in functions that return 'int'") +__naked void ld_abs_void_subprog_reject(void) +{ + asm volatile ( + "call ldabs_void_subprog;" + "r0 = 0;" + "exit;" + ::: __clobber_all); +} + +__naked __noinline __used +static void ldind_void_subprog(void) +{ + asm volatile ( + "r6 = r1;" + "r7 = 0;" + ".8byte %[ld_ind];" + "r0 = 1;" + "exit;" + : + : __imm_insn(ld_ind, BPF_LD_IND(BPF_W, BPF_REG_7, 0)) + : __clobber_all); +} + +SEC("socket") +__description("ld_ind: reject void return subprog") +__failure __msg("LD_ABS is only allowed in functions that return 'int'") +__naked void ld_ind_void_subprog_reject(void) +{ + asm volatile ( + "call ldind_void_subprog;" + "r0 = 0;" + "exit;" + ::: __clobber_all); +} + char _license[] SEC("license") = "GPL"; -- 2.53.0