From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-171.mta0.migadu.com (out-171.mta0.migadu.com [91.218.175.171]) (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 A09E72DF3EC for ; Tue, 16 Sep 2025 05:42:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.171 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758001353; cv=none; b=nbdYr8mAJ4Yo1s7yfpacv2LSawGrxSYK6xs2jW9Bzri9UEfxxC3rQpeEAD3CGPUui8gabj0A+BqEBdsCMHtSVIAzWc1CjdfnH/JQu1gROkWXW+L6JMF65Kx2jPaCbi4ToLZtJo7Jnkt57hVP8oY9C7R93ZX/Lan3/OTnAYjPVoo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758001353; c=relaxed/simple; bh=6HwE6Pr1FMZJQJTx/nBTHBpVYjdfFe2TgsDwHZ1v5Gs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=FvqdSlCvRs2pIe6OzyylVungqpr3+wupmejnM6GgFzid5vTY0aX8qU8xryNkY81JzDOnEX8Iif7TNwMxsFsp+Q7t98EJLl6H41C06la7WreYKwu7ZoxglTPuyuex//Wako20NHv4snXkv3rkT1XWvM3rshGAqw8E4Btwa//5kQ0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=TJoAfaGM; arc=none smtp.client-ip=91.218.175.171 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="TJoAfaGM" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1758001338; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=+PBqXqIBAXliLEIaRmiKltx7PaLxbdrR9kdSsL/p1Hw=; b=TJoAfaGMOnVb76fecDrUAtJ4mE+ril5ZZgma0CWR4buu7dA7B0TlSumJB8GE8LiR8B5/sk gyA2dY7vOFWHtYtmMMQ556HY7ur9WATmuRpkbZPND4UiSwGIe7QDadE3x3EvYQaXfm7gx8 +VoovEFN2HlSFIHxxaXh0sKj1Mbjp+w= From: Tao Chen To: qmo@kernel.org, ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, martin.lau@linux.dev, eddyz87@gmail.com, song@kernel.org, yonghong.song@linux.dev, john.fastabend@gmail.com, kpsingh@kernel.org, sdf@fomichev.me, haoluo@google.com, jolsa@kernel.org, chen.dylane@linux.dev Cc: bpf@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH bpf-next 2/2] bpftool: Fix UAF in get_delegate_value Date: Tue, 16 Sep 2025 13:41:11 +0800 Message-ID: <20250916054111.1151487-2-chen.dylane@linux.dev> In-Reply-To: <20250916054111.1151487-1-chen.dylane@linux.dev> References: <20250916054111.1151487-1-chen.dylane@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT The return value ret pointer is pointing opts_copy, but opts_copy gets freed in get_delegate_value before return, fix this by strdup a new buffer. Fixes: 2d812311c2b2 ("bpftool: Add bpf_token show") Signed-off-by: Tao Chen --- tools/bpf/bpftool/token.c | 47 ++++++++++++++++++++++----------------- 1 file changed, 27 insertions(+), 20 deletions(-) diff --git a/tools/bpf/bpftool/token.c b/tools/bpf/bpftool/token.c index 82b829e44c8..c47256d8038 100644 --- a/tools/bpf/bpftool/token.c +++ b/tools/bpf/bpftool/token.c @@ -28,6 +28,12 @@ static bool has_delegate_options(const char *mnt_ops) strstr(mnt_ops, "delegate_attachs"); } +static void free_delegate_value(char *value) +{ + if (value) + free(value); +} + static char *get_delegate_value(const char *opts, const char *key) { char *token, *rest, *ret = NULL; @@ -40,7 +46,7 @@ static char *get_delegate_value(const char *opts, const char *key) token = strtok_r(NULL, ",", &rest)) { if (strncmp(token, key, strlen(key)) == 0 && token[strlen(key)] == '=') { - ret = token + strlen(key) + 1; + ret = strdup(token + strlen(key) + 1); break; } } @@ -73,28 +79,29 @@ static void print_items_per_line(const char *input, int items_per_line) free(strs); } +#define PRINT_DELEGATE_OPT(opt_name) do { \ + char *value = get_delegate_value(mntent->mnt_opts, opt_name); \ + print_items_per_line(value, ITEMS_PER_LINE); \ + free_delegate_value(value); \ +} while (0) + #define ITEMS_PER_LINE 4 static void show_token_info_plain(struct mntent *mntent) { - char *value; printf("token_info %s", mntent->mnt_dir); printf("\n\tallowed_cmds:"); - value = get_delegate_value(mntent->mnt_opts, "delegate_cmds"); - print_items_per_line(value, ITEMS_PER_LINE); + PRINT_DELEGATE_OPT("delegate_cmds"); printf("\n\tallowed_maps:"); - value = get_delegate_value(mntent->mnt_opts, "delegate_maps"); - print_items_per_line(value, ITEMS_PER_LINE); + PRINT_DELEGATE_OPT("delegate_maps"); printf("\n\tallowed_progs:"); - value = get_delegate_value(mntent->mnt_opts, "delegate_progs"); - print_items_per_line(value, ITEMS_PER_LINE); + PRINT_DELEGATE_OPT("delegate_progs"); printf("\n\tallowed_attachs:"); - value = get_delegate_value(mntent->mnt_opts, "delegate_attachs"); - print_items_per_line(value, ITEMS_PER_LINE); + PRINT_DELEGATE_OPT("delegate_attachs"); printf("\n"); } @@ -122,29 +129,29 @@ static void split_json_array_str(const char *input) free(strs); } +#define PRINT_DELEGATE_OPT_JSON(opt_name) do { \ + char *value = get_delegate_value(mntent->mnt_opts, opt_name); \ + split_json_array_str(value); \ + free_delegate_value(value); \ +} while (0) + static void show_token_info_json(struct mntent *mntent) { - char *value; - jsonw_start_object(json_wtr); jsonw_string_field(json_wtr, "token_info", mntent->mnt_dir); jsonw_name(json_wtr, "allowed_cmds"); - value = get_delegate_value(mntent->mnt_opts, "delegate_cmds"); - split_json_array_str(value); + PRINT_DELEGATE_OPT_JSON("delegate_cmds"); jsonw_name(json_wtr, "allowed_maps"); - value = get_delegate_value(mntent->mnt_opts, "delegate_maps"); - split_json_array_str(value); + PRINT_DELEGATE_OPT_JSON("delegate_maps"); jsonw_name(json_wtr, "allowed_progs"); - value = get_delegate_value(mntent->mnt_opts, "delegate_progs"); - split_json_array_str(value); + PRINT_DELEGATE_OPT_JSON("delegate_progs"); jsonw_name(json_wtr, "allowed_attachs"); - value = get_delegate_value(mntent->mnt_opts, "delegate_attachs"); - split_json_array_str(value); + PRINT_DELEGATE_OPT_JSON("delegate_attachs"); jsonw_end_object(json_wtr); } -- 2.48.1