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 2E94935C1BC; Sat, 17 Oct 2026 16:17:10 +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=1792253831; cv=none; b=V66/heQVYBw8TWvvzbjZqpfjQ0i9zGTEPwscoP9rhLwl46BoOVgNqui1BgWsOrOyrFozuEINox3iV4XCEEASqja0N7MUQa1tRLNoDQajauOuCujEmway0SdJFZSKDvAt7J+yf0nUHNhJRc1XWAD7Ilnlj1Z8Vs6zgBHfw3N0Y2o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792253831; c=relaxed/simple; bh=g4Gn1f63//6A4x64NlGSI4xpZkaZnwWDX5FRBV41Bwk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=r8/RWZiq1A/BR+ghNx1LuDowuKgEnCXhX2ElV87cVWLMC1AFNEJjoVpKQ5yjbMyXsXu4WeBxzHcLFIniIi7nrulMqVPMh490ctroQE4an8wfJZWPaPi/CjI5oYmJCKcNZaL2xAeu9xdsXJ8vMgdn9VhvX986kRqm0BW4qasWe3M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=i6jIVhfg; 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="i6jIVhfg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 795AC1F000C4; Sat, 17 Oct 2026 16:17:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1792253830; bh=QaOvW5YIkKb9kPrKeGxyaoiBjeKBcWHMy/Svj8bAoAU=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=i6jIVhfg3cKIthqt4qe2gGI3Z89oE3VYGkpGJ2KblZ9wTRrY9Z7VcRCH8bYf2zyYk Oy6Tpm7bmUoy4M3oUQ5tWYPYHSgDVMEu6LcrJFwCwEZEfJr7aOjY6Evz0bIp7lTku0 CiFmmk3ujWQ1AiqZRfKPKHq9hWD5fyYiGlJ3fLmU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Peilin Ye , Alexei Starovoitov , Sasha Levin Subject: [PATCH 6.12 207/869] bpf: Factor out atomic_ptr_type_ok() Date: Sat, 17 Oct 2026 17:50:48 +0200 Message-ID: <20261017160042.362738909@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261017160036.979869304@linuxfoundation.org> References: <20261017160036.979869304@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: Peilin Ye [ Upstream commit 66faaea94e1a8e8197d98de6e9d07591970837d6 ] Factor out atomic_ptr_type_ok() as a helper function to be used later. Signed-off-by: Peilin Ye Link: https://lore.kernel.org/r/e5ef8b3116f3fffce78117a14060ddce05eba52a.1740978603.git.yepeilin@google.com Signed-off-by: Alexei Starovoitov Stable-dep-of: 179ee84a8911 ("bpf: Fix incorrect pruning due to atomic fetch precision tracking") Signed-off-by: Sasha Levin --- kernel/bpf/verifier.c | 26 +++++++++++++++++++++----- 1 file changed, 21 insertions(+), 5 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 4978c1d68bd98..1f5c8b5b74ffb 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -5986,6 +5986,26 @@ static bool is_arena_reg(struct bpf_verifier_env *env, int regno) return reg->type == PTR_TO_ARENA; } +/* Return false if @regno contains a pointer whose type isn't supported for + * atomic instruction @insn. + */ +static bool atomic_ptr_type_ok(struct bpf_verifier_env *env, int regno, + struct bpf_insn *insn) +{ + if (is_ctx_reg(env, regno)) + return false; + if (is_pkt_reg(env, regno)) + return false; + if (is_flow_key_reg(env, regno)) + return false; + if (is_sk_reg(env, regno)) + return false; + if (is_arena_reg(env, regno)) + return bpf_jit_supports_insn(insn, true); + + return true; +} + static u32 *reg2btf_ids[__BPF_REG_TYPE_MAX] = { #ifdef CONFIG_NET [PTR_TO_SOCKET] = &btf_sock_ids[BTF_SOCK_TYPE_SOCK], @@ -7439,11 +7459,7 @@ static int check_atomic(struct bpf_verifier_env *env, int insn_idx, struct bpf_i return -EACCES; } - if (is_ctx_reg(env, insn->dst_reg) || - is_pkt_reg(env, insn->dst_reg) || - is_flow_key_reg(env, insn->dst_reg) || - is_sk_reg(env, insn->dst_reg) || - (is_arena_reg(env, insn->dst_reg) && !bpf_jit_supports_insn(insn, true))) { + if (!atomic_ptr_type_ok(env, insn->dst_reg, insn)) { verbose(env, "BPF_ATOMIC stores into R%d %s is not allowed\n", insn->dst_reg, reg_type_str(env, reg_state(env, insn->dst_reg)->type)); -- 2.53.0