[bpf-next] selftests/bpf: Load struct_ops map in global_maps_resize test

Commit Message

David Vernet July 25, 2024, 3:22 a.m. UTC

In prog_tests/test_global_maps_resize.c, we test various use cases for
resizing global maps. Commit 7244100e0389 ("libbpf: Don't take direct
pointers into BTF data from st_ops") updated libbpf to not store pointers
to volatile BTF data, which for some users, was causing a UAF when resizing
a datasec array.

Let's ensure we have coverage for resizing datasec arrays with struct_ops
progs by also including a struct_ops map and struct_ops prog in the
test_global_map_resize skeleton. The map is automatically loaded, so we
don't need to do anything other than add it to the BPF prog being tested
to get the coverage.

Signed-off-by: David Vernet <[e-mail]>
---
 .../selftests/bpf/progs/test_global_map_resize.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

Comments

[e-mail] July 25, 2024, 8:40 p.m. UTC | #1

Hello:

This patch was applied to bpf/bpf-next.git (master)
by Andrii Nakryiko <[e-mail]>:

On Wed, 24 Jul 2024 22:22:14 -0500 you wrote:
> In prog_tests/test_global_maps_resize.c, we test various use cases for
> resizing global maps. Commit 7244100e0389 ("libbpf: Don't take direct
> pointers into BTF data from st_ops") updated libbpf to not store pointers
> to volatile BTF data, which for some users, was causing a UAF when resizing
> a datasec array.
> 
> Let's ensure we have coverage for resizing datasec arrays with struct_ops
> progs by also including a struct_ops map and struct_ops prog in the
> test_global_map_resize skeleton. The map is automatically loaded, so we
> don't need to do anything other than add it to the BPF prog being tested
> to get the coverage.
> 
> [...]

Here is the summary with links:
  - [bpf-next] selftests/bpf: Load struct_ops map in global_maps_resize test
    https://git.kernel.org/bpf/bpf-next/c/7d30b8aa4fc3

You are awesome, thank you!

Patch

diff --git a/tools/testing/selftests/bpf/progs/test_global_map_resize.c b/tools/testing/selftests/bpf/progs/test_global_map_resize.c
index 1fbb73d3e5d5..714b29c7f8b2 100644
--- a/tools/testing/selftests/bpf/progs/test_global_map_resize.c
+++ b/tools/testing/selftests/bpf/progs/test_global_map_resize.c
@@ -3,6 +3,7 @@ 
 
 #include "vmlinux.h"
 #include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
 
 char _license[] SEC("license") = "GPL";
 
@@ -60,3 +61,18 @@  int data_array_sum(void *ctx)
 
 	return 0;
 }
+
+SEC("struct_ops/test_1")
+int BPF_PROG(test_1)
+{
+	return 0;
+}
+
+struct bpf_testmod_ops {
+	int (*test_1)(void);
+};
+
+SEC(".struct_ops.link")
+struct bpf_testmod_ops st_ops_resize = {
+	.test_1 = (void *)test_1
+};