[PATCH 5.10 30/30] Revert "selftests/bpf: Add test for bpf_timer overwriting crash"

Greg Kroah-Hartman
2022-03-21T14:12:12Z

From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This reverts commit 4fb9be675be8360bede6fb8f0cad7948393fbef8 which is
commit a7e75016a0753c24d6c995bc02501ae35368e333 upstream.

It is reported to break the bpf self-tests.

Reported-by: Geliang Tang <geliang.tang@suse.com>
Reported-by: Tommi Rantala <tommi.t.rantala@nokia.com>
Cc: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220209070324.1093182-3-memxor@gmail.com
Cc: Sasha Levin <sashal@kernel.org>
Link: https://lore.kernel.org/r/a0a7298ca5c64b3d0ecfcc8821c2de79186fa9f7.camel@nokia.com
Link: https://lore.kernel.org/r/HE1PR0402MB3497CB13A12C4D15D20A1FCCF8139@HE1PR0402MB3497.eurprd04.prod.outlook.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
tools/testing/selftests/bpf/prog_tests/timer_crash.c | 32 -----------
tools/testing/selftests/bpf/progs/timer_crash.c | 54 -------------------
2 files changed, 86 deletions(-)
delete mode 100644 tools/testing/selftests/bpf/prog_tests/timer_crash.c
delete mode 100644 tools/testing/selftests/bpf/progs/timer_crash.c

--- a/tools/testing/selftests/bpf/prog_tests/timer_crash.c
+++ /dev/null
@@ -1,32 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-#include <test_progs.h>
-#include "timer_crash.skel.h"
-
-enum {
- MODE_ARRAY,
- MODE_HASH,
-};
-
-static void test_timer_crash_mode(int mode)
-{
- struct timer_crash *skel;
-
- skel = timer_crash__open_and_load();
- if (!ASSERT_OK_PTR(skel, "timer_crash__open_and_load"))
- return;
- skel->bss->pid = getpid();
- skel->bss->crash_map = mode;
- if (!ASSERT_OK(timer_crash__attach(skel), "timer_crash__attach"))
- goto end;
- usleep(1);
-end:
- timer_crash__destroy(skel);
-}
-
-void test_timer_crash(void)
-{
- if (test__start_subtest("array"))
- test_timer_crash_mode(MODE_ARRAY);
- if (test__start_subtest("hash"))
- test_timer_crash_mode(MODE_HASH);
-}
--- a/tools/testing/selftests/bpf/progs/timer_crash.c
+++ /dev/null
@@ -1,54 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-
-#include <vmlinux.h>
-#include <bpf/bpf_tracing.h>
-#include <bpf/bpf_helpers.h>
-
-struct map_elem {
- struct bpf_timer timer;
- struct bpf_spin_lock lock;
-};
-
-struct {
- __uint(type, BPF_MAP_TYPE_ARRAY);
- __uint(max_entries, 1);
- __type(key, int);
- __type(value, struct map_elem);
-} amap SEC(".maps");
-
-struct {
- __uint(type, BPF_MAP_TYPE_HASH);
- __uint(max_entries, 1);
- __type(key, int);
- __type(value, struct map_elem);
-} hmap SEC(".maps");
-
-int pid = 0;
-int crash_map = 0; /* 0 for amap, 1 for hmap */
-
-SEC("fentry/do_nanosleep")
-int sys_enter(void *ctx)
-{
- struct map_elem *e, value = {};
- void *map = crash_map ? (void *)&hmap : (void *)&amap;
-
- if (bpf_get_current_task_btf()->tgid != pid)
- return 0;
-
- *(void **)&value = (void *)0xdeadcaf3;
-
- bpf_map_update_elem(map, &(int){0}, &value, 0);
- /* For array map, doing bpf_map_update_elem will do a
- * check_and_free_timer_in_array, which will trigger the crash if timer
- * pointer was overwritten, for hmap we need to use bpf_timer_cancel.
- */
- if (crash_map == 1) {
- e = bpf_map_lookup_elem(map, &(int){0});
- if (!e)
- return 0;
- bpf_timer_cancel(&e->timer);
- }
- return 0;
-}
-
-char _license[] SEC("license") = "GPL";