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 8BA6B13C3F5; Tue, 14 May 2024 11:32:21 +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=1715686341; cv=none; b=AXGOPKPZyCd+PEOGtXFr9/4QMhN3VZ2JSWCdlYF8ixLUtcXdbTlDvpmRJhjwRCeikVXysNQrEIk6owQ9Ojj6UNMnHcnKceEYTz6IvroUcDGNkUvauHImAqp/VfUL7AK/+FPCxQ7hnoj3hpswLZaDzafB+oEwIk6cZmFRbsxwqAo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715686341; c=relaxed/simple; bh=xKVCEx8qhNOV7NO4wShED/uDsd5kqQPX/tXx2PMHfHI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=MQzFEP7jb2SwpYFCvqFHlEVwz2zu2VRMMEaa8EH2XYuQ3GLKRiV/Zzxm9ThF8hfO6lm2FxwRUkXqg44cI4azdjFCHaU794I7gM6MIwSx7DW5CqvqC1gygnOP9XFMMFotn03QgZGLt2WrS2MwtBRb3cjOKqbgJfmw6XJBMAdw62g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=VQOqebdn; 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="VQOqebdn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 137CFC2BD10; Tue, 14 May 2024 11:32:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1715686341; bh=xKVCEx8qhNOV7NO4wShED/uDsd5kqQPX/tXx2PMHfHI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VQOqebdn+avRtNJ+oAxwxEdemGr9IMRDAIyGxmWhtIxFp1yTuEB0U4YrjboqBLXDR QudE5ubOoDmxZLEoXAM4iJaOA60EHZFoEdUqOmrBkqKz2taosYgMCh4UayKbWTvD+N OIHgWdg3ZUfRCsZ68twIuPZYh5mcUJqcv+zX7RJA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Andrei Matei , Andrii Nakryiko , Alexei Starovoitov , Sasha Levin Subject: [PATCH 6.1 104/236] bpf: Check bloom filter map value size Date: Tue, 14 May 2024 12:17:46 +0200 Message-ID: <20240514101024.318388766@linuxfoundation.org> X-Mailer: git-send-email 2.45.0 In-Reply-To: <20240514101020.320785513@linuxfoundation.org> References: <20240514101020.320785513@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 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Andrei Matei [ Upstream commit a8d89feba7e54e691ca7c4efc2a6264fa83f3687 ] This patch adds a missing check to bloom filter creating, rejecting values above KMALLOC_MAX_SIZE. This brings the bloom map in line with many other map types. The lack of this protection can cause kernel crashes for value sizes that overflow int's. Such a crash was caught by syzkaller. The next patch adds more guard-rails at a lower level. Signed-off-by: Andrei Matei Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/r/20240327024245.318299-2-andreimatei1@gmail.com Signed-off-by: Alexei Starovoitov Signed-off-by: Sasha Levin --- kernel/bpf/bloom_filter.c | 13 +++++++++++++ .../selftests/bpf/prog_tests/bloom_filter_map.c | 6 ++++++ 2 files changed, 19 insertions(+) diff --git a/kernel/bpf/bloom_filter.c b/kernel/bpf/bloom_filter.c index 48ee750849f25..78e810f49c445 100644 --- a/kernel/bpf/bloom_filter.c +++ b/kernel/bpf/bloom_filter.c @@ -88,6 +88,18 @@ static int bloom_map_get_next_key(struct bpf_map *map, void *key, void *next_key return -EOPNOTSUPP; } +/* Called from syscall */ +static int bloom_map_alloc_check(union bpf_attr *attr) +{ + if (attr->value_size > KMALLOC_MAX_SIZE) + /* if value_size is bigger, the user space won't be able to + * access the elements. + */ + return -E2BIG; + + return 0; +} + static struct bpf_map *bloom_map_alloc(union bpf_attr *attr) { u32 bitset_bytes, bitset_mask, nr_hash_funcs, nr_bits; @@ -196,6 +208,7 @@ static int bloom_map_check_btf(const struct bpf_map *map, BTF_ID_LIST_SINGLE(bpf_bloom_map_btf_ids, struct, bpf_bloom_filter) const struct bpf_map_ops bloom_filter_map_ops = { .map_meta_equal = bpf_map_meta_equal, + .map_alloc_check = bloom_map_alloc_check, .map_alloc = bloom_map_alloc, .map_free = bloom_map_free, .map_get_next_key = bloom_map_get_next_key, diff --git a/tools/testing/selftests/bpf/prog_tests/bloom_filter_map.c b/tools/testing/selftests/bpf/prog_tests/bloom_filter_map.c index d2d9e965eba59..f79815b7e951b 100644 --- a/tools/testing/selftests/bpf/prog_tests/bloom_filter_map.c +++ b/tools/testing/selftests/bpf/prog_tests/bloom_filter_map.c @@ -2,6 +2,7 @@ /* Copyright (c) 2021 Facebook */ #include +#include #include #include "bloom_filter_map.skel.h" @@ -21,6 +22,11 @@ static void test_fail_cases(void) if (!ASSERT_LT(fd, 0, "bpf_map_create bloom filter invalid value size 0")) close(fd); + /* Invalid value size: too big */ + fd = bpf_map_create(BPF_MAP_TYPE_BLOOM_FILTER, NULL, 0, INT32_MAX, 100, NULL); + if (!ASSERT_LT(fd, 0, "bpf_map_create bloom filter invalid value too large")) + close(fd); + /* Invalid max entries size */ fd = bpf_map_create(BPF_MAP_TYPE_BLOOM_FILTER, NULL, 0, sizeof(value), 0, NULL); if (!ASSERT_LT(fd, 0, "bpf_map_create bloom filter invalid max entries size")) -- 2.43.0