From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 C867A2BB1B; Fri, 15 Nov 2024 06:48:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731653339; cv=none; b=R1MNTG4MxARlMl14j73GwKWMb7FM7CuPhzM6oXmy0d85cU5iviIUlCdpykFUNkZURX7rpLzR9R+71Jt9pRInKKh9G0Qv2OgyZcKtVTN5C8+Nta2vPSbPMG/P1X+zVNceG+K3qRQkmaU5tH1ZjcYYFiP46qwi6XvKUE6iyeoigqI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731653339; c=relaxed/simple; bh=wQG0VW6v/0Dr54xvykwlRPG22nki01XYYFh3kqjBIL0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=cGmLbDrp7cDeLznHUcrstExWQP9514Aue+Pas0OWEHvcmcE5lQQsvdGz3NauKWFWjUOforNs5tI1HSv4t92VH+zC8Vd4SZZPMsK1HfpiPAWRFgbWzVoGOFVtwQUb8zgw1DZ4JCYD1R4n/4ofEiSjKAJxl1vTlE/+6SxWovk3klk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=B3v6ZQU0; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="B3v6ZQU0" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 35363C4CECF; Fri, 15 Nov 2024 06:48:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1731653339; bh=wQG0VW6v/0Dr54xvykwlRPG22nki01XYYFh3kqjBIL0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=B3v6ZQU0AX4OlMwbFh+p3TESMSHoa0Cs4a2bHsBbGEzY1iAdDJL5hZXFUBYnpb0PH wh0UXPZX3YN4bpM/PMnnrua7G2O6wuZeWqtFp3BbWf9fB7tdI2YSdiSfxFnWUfCwr3 m1ZKtYAV8Xk87qEziYKA666ukEvrY+zEst2/EUqo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Hou Tao , Andrii Nakryiko , Sasha Levin Subject: [PATCH 6.11 56/63] bpf: Check validity of link->type in bpf_link_show_fdinfo() Date: Fri, 15 Nov 2024 07:38:19 +0100 Message-ID: <20241115063727.930162831@linuxfoundation.org> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241115063725.892410236@linuxfoundation.org> References: <20241115063725.892410236@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.11-stable review patch. If anyone has any objections, please let me know. ------------------ From: Hou Tao [ Upstream commit 8421d4c8762bd022cb491f2f0f7019ef51b4f0a7 ] If a newly-added link type doesn't invoke BPF_LINK_TYPE(), accessing bpf_link_type_strs[link->type] may result in an out-of-bounds access. To spot such missed invocations early in the future, checking the validity of link->type in bpf_link_show_fdinfo() and emitting a warning when such invocations are missed. Signed-off-by: Hou Tao Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20241024013558.1135167-3-houtao@huaweicloud.com Signed-off-by: Sasha Levin --- kernel/bpf/syscall.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 19b590b5aaec9..b282ed1250358 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -3136,13 +3136,17 @@ static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp) { const struct bpf_link *link = filp->private_data; const struct bpf_prog *prog = link->prog; + enum bpf_link_type type = link->type; char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; - seq_printf(m, - "link_type:\t%s\n" - "link_id:\t%u\n", - bpf_link_type_strs[link->type], - link->id); + if (type < ARRAY_SIZE(bpf_link_type_strs) && bpf_link_type_strs[type]) { + seq_printf(m, "link_type:\t%s\n", bpf_link_type_strs[type]); + } else { + WARN_ONCE(1, "missing BPF_LINK_TYPE(...) for link type %u\n", type); + seq_printf(m, "link_type:\t<%u>\n", type); + } + seq_printf(m, "link_id:\t%u\n", link->id); + if (prog) { bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); seq_printf(m, -- 2.43.0