linux-kernel - [PATCH 4.9 59/65] bpf: fix wrong exposure of map

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Fri,  9 Mar 2018 16:18:59 -0800
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, ast@...nel.org, daniel@...earbox.net,
        "David S . Miller" <davem@...emloft.net>,
        Jarno Rajahalme <jarno@...alent.io>
Subject: [PATCH 4.9 59/65] bpf: fix wrong exposure of map_flags into fdinfo for lpm

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Daniel Borkmann <daniel@...earbox.net>

[ upstream commit a316338cb71a3260201490e615f2f6d5c0d8fb2c ]

trie_alloc() always needs to have BPF_F_NO_PREALLOC passed in via
attr->map_flags, since it does not support preallocation yet. We
check the flag, but we never copy the flag into trie->map.map_flags,
which is later on exposed into fdinfo and used by loaders such as
iproute2. Latter uses this in bpf_map_selfcheck_pinned() to test
whether a pinned map has the same spec as the one from the BPF obj
file and if not, bails out, which is currently the case for lpm
since it exposes always 0 as flags.

Also copy over flags in array_map_alloc() and stack_map_alloc().
They always have to be 0 right now, but we should make sure to not
miss to copy them over at a later point in time when we add actual
flags for them to use.

Fixes: b95a5c4db09b ("bpf: add a longest prefix match trie map implementation")
Reported-by: Jarno Rajahalme <jarno@...alent.io>
Signed-off-by: Daniel Borkmann <daniel@...earbox.net>
Acked-by: Alexei Starovoitov <ast@...nel.org>
Signed-off-by: David S. Miller <davem@...emloft.net>
Signed-off-by: Daniel Borkmann <daniel@...earbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 kernel/bpf/arraymap.c |    1 +
 kernel/bpf/stackmap.c |    1 +
 2 files changed, 2 insertions(+)

--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -107,6 +107,7 @@ static struct bpf_map *array_map_alloc(u
 	array->map.key_size = attr->key_size;
 	array->map.value_size = attr->value_size;
 	array->map.max_entries = attr->max_entries;
+	array->map.map_flags = attr->map_flags;
 	array->elem_size = elem_size;

 	if (!percpu)
--- a/kernel/bpf/stackmap.c
+++ b/kernel/bpf/stackmap.c
@@ -88,6 +88,7 @@ static struct bpf_map *stack_map_alloc(u
 	smap->map.key_size = attr->key_size;
 	smap->map.value_size = value_size;
 	smap->map.max_entries = attr->max_entries;
+	smap->map.map_flags = attr->map_flags;
 	smap->n_buckets = n_buckets;
 	smap->map.pages = round_up(cost, PAGE_SIZE) >> PAGE_SHIFT;