| Message ID | 20220406085408.339336-1-asavkov@redhat.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | ebaf24c589d7c714b763a80856d1a6df3ba25b84 |
| Delegated to: | BPF |
| Headers | show |
| Series | [bpf-next] bpf/selftests: use bpf_num_possible_cpus() in per-cpu map allocations | expand |
Hello: This patch was applied to bpf/bpf-next.git (master) by Andrii Nakryiko <andrii@kernel.org>: On Wed, 6 Apr 2022 10:54:08 +0200 you wrote: > bpf_map_value_size() uses num_possible_cpus() to determine map size, but > some of the tests only allocate enough memory for online cpus. This > results in out-of-bound writes in userspace during bpf(BPF_MAP_LOOKUP_ELEM) > syscalls in cases when number of online cpus is lower than the number of > possible cpus. Fix by switching from get_nprocs_conf() to > bpf_num_possible_cpus() when determining the number of processors in > these tests (test_progs/netcnt and test_cgroup_storage). > > [...] Here is the summary with links: - [bpf-next] bpf/selftests: use bpf_num_possible_cpus() in per-cpu map allocations https://git.kernel.org/bpf/bpf-next/c/ebaf24c589d7 You are awesome, thank you!
diff --git a/tools/testing/selftests/bpf/prog_tests/netcnt.c b/tools/testing/selftests/bpf/prog_tests/netcnt.c index 954964f0ac3d..d3915c58d0e1 100644 --- a/tools/testing/selftests/bpf/prog_tests/netcnt.c +++ b/tools/testing/selftests/bpf/prog_tests/netcnt.c @@ -25,7 +25,7 @@ void serial_test_netcnt(void) if (!ASSERT_OK_PTR(skel, "netcnt_prog__open_and_load")) return; - nproc = get_nprocs_conf(); + nproc = bpf_num_possible_cpus(); percpu_netcnt = malloc(sizeof(*percpu_netcnt) * nproc); if (!ASSERT_OK_PTR(percpu_netcnt, "malloc(percpu_netcnt)")) goto err; diff --git a/tools/testing/selftests/bpf/test_cgroup_storage.c b/tools/testing/selftests/bpf/test_cgroup_storage.c index d6a1be4d8020..2ffa08198d1c 100644 --- a/tools/testing/selftests/bpf/test_cgroup_storage.c +++ b/tools/testing/selftests/bpf/test_cgroup_storage.c @@ -7,6 +7,7 @@ #include <sys/sysinfo.h> #include "bpf_rlimit.h" +#include "bpf_util.h" #include "cgroup_helpers.h" #include "testing_helpers.h" @@ -44,7 +45,7 @@ int main(int argc, char **argv) unsigned long long *percpu_value; int cpu, nproc; - nproc = get_nprocs_conf(); + nproc = bpf_num_possible_cpus(); percpu_value = malloc(sizeof(*percpu_value) * nproc); if (!percpu_value) { printf("Not enough memory for per-cpu area (%d cpus)\n", nproc);
bpf_map_value_size() uses num_possible_cpus() to determine map size, but some of the tests only allocate enough memory for online cpus. This results in out-of-bound writes in userspace during bpf(BPF_MAP_LOOKUP_ELEM) syscalls in cases when number of online cpus is lower than the number of possible cpus. Fix by switching from get_nprocs_conf() to bpf_num_possible_cpus() when determining the number of processors in these tests (test_progs/netcnt and test_cgroup_storage). Signed-off-by: Artem Savkov <asavkov@redhat.com> --- tools/testing/selftests/bpf/prog_tests/netcnt.c | 2 +- tools/testing/selftests/bpf/test_cgroup_storage.c | 3 ++- 2 files changed, 3 insertions(+), 2 deletions(-)