summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorToke Høiland-Jørgensen <toke@redhat.com>2020-04-16 10:31:20 +0200
committerAlexei Starovoitov <ast@kernel.org>2020-04-20 18:38:04 -0700
commitbc23d0e3f717ced21fbfacab3ab887d55e5ba367 (patch)
treed9b55b22a3c6429936b2b7d5d5b3b6b129845a1b
parenta460fc5d4c170806a31e590df37ead3ab951315c (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.c2
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) {