diff options
author | Toke Høiland-Jørgensen <toke@redhat.com> | 2020-04-16 10:31:20 +0200 |
---|---|---|
committer | Alexei Starovoitov <ast@kernel.org> | 2020-04-20 18:38:04 -0700 |
commit | bc23d0e3f717ced21fbfacab3ab887d55e5ba367 (patch) | |
tree | d9b55b22a3c6429936b2b7d5d5b3b6b129845a1b | |
parent | a460fc5d4c170806a31e590df37ead3ab951315c (diff) |
cpumap: Avoid warning when CONFIG_DEBUG_PER_CPU_MAPS is enabled
When the kernel is built with CONFIG_DEBUG_PER_CPU_MAPS, the cpumap code
can trigger a spurious warning if CONFIG_CPUMASK_OFFSTACK is also set. This
happens because in this configuration, NR_CPUS can be larger than
nr_cpumask_bits, so the initial check in cpu_map_alloc() is not sufficient
to guard against hitting the warning in cpumask_check().
Fix this by explicitly checking the supplied key against the
nr_cpumask_bits variable before calling cpu_possible().
Fixes: 6710e1126934 ("bpf: introduce new bpf cpu map type BPF_MAP_TYPE_CPUMAP")
Reported-by: Xiumei Mu <xmu@redhat.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Xiumei Mu <xmu@redhat.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200416083120.453718-1-toke@redhat.com
-rw-r--r-- | kernel/bpf/cpumap.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c index 70f71b154fa5..3fe0b006d2d2 100644 --- a/kernel/bpf/cpumap.c +++ b/kernel/bpf/cpumap.c @@ -469,7 +469,7 @@ static int cpu_map_update_elem(struct bpf_map *map, void *key, void *value, return -EOVERFLOW; /* Make sure CPU is a valid possible cpu */ - if (!cpu_possible(key_cpu)) + if (key_cpu >= nr_cpumask_bits || !cpu_possible(key_cpu)) return -ENODEV; if (qsize == 0) { |