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authorDavid S. Miller <davem@davemloft.net>2019-06-20 00:06:27 -0400
committerDavid S. Miller <davem@davemloft.net>2019-06-20 00:06:27 -0400
commitdca73a65a68329ee386d3ff473152bac66eaab39 (patch)
tree97c41afb932bdd6cbe67e7ffc38bfe5952c97798 /tools/testing/selftests/bpf/progs/test_sysctl_loop2.c
parent497ad9f5b2dc86b733761b9afa44ecfa2f17be65 (diff)
parent94079b64255fe40b9b53fd2e4081f68b9b14f54a (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says: ==================== pull-request: bpf-next 2019-06-19 The following pull-request contains BPF updates for your *net-next* tree. The main changes are: 1) new SO_REUSEPORT_DETACH_BPF setsocktopt, from Martin. 2) BTF based map definition, from Andrii. 3) support bpf_map_lookup_elem for xskmap, from Jonathan. 4) bounded loops and scalar precision logic in the verifier, from Alexei. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'tools/testing/selftests/bpf/progs/test_sysctl_loop2.c')
-rw-r--r--tools/testing/selftests/bpf/progs/test_sysctl_loop2.c72
1 files changed, 72 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/test_sysctl_loop2.c b/tools/testing/selftests/bpf/progs/test_sysctl_loop2.c
new file mode 100644
index 000000000000..cb201cbe11e7
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_sysctl_loop2.c
@@ -0,0 +1,72 @@
1// SPDX-License-Identifier: GPL-2.0
2// Copyright (c) 2019 Facebook
3
4#include <stdint.h>
5#include <string.h>
6
7#include <linux/stddef.h>
8#include <linux/bpf.h>
9
10#include "bpf_helpers.h"
11
12#ifndef ARRAY_SIZE
13#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
14#endif
15
16/* tcp_mem sysctl has only 3 ints, but this test is doing TCP_MEM_LOOPS */
17#define TCP_MEM_LOOPS 20 /* because 30 doesn't fit into 512 bytes of stack */
18#define MAX_ULONG_STR_LEN 7
19#define MAX_VALUE_STR_LEN (TCP_MEM_LOOPS * MAX_ULONG_STR_LEN)
20
21static __attribute__((noinline)) int is_tcp_mem(struct bpf_sysctl *ctx)
22{
23 volatile char tcp_mem_name[] = "net/ipv4/tcp_mem/very_very_very_very_long_pointless_string_to_stress_byte_loop";
24 unsigned char i;
25 char name[64];
26 int ret;
27
28 memset(name, 0, sizeof(name));
29 ret = bpf_sysctl_get_name(ctx, name, sizeof(name), 0);
30 if (ret < 0 || ret != sizeof(tcp_mem_name) - 1)
31 return 0;
32
33#pragma clang loop unroll(disable)
34 for (i = 0; i < sizeof(tcp_mem_name); ++i)
35 if (name[i] != tcp_mem_name[i])
36 return 0;
37
38 return 1;
39}
40
41
42SEC("cgroup/sysctl")
43int sysctl_tcp_mem(struct bpf_sysctl *ctx)
44{
45 unsigned long tcp_mem[TCP_MEM_LOOPS] = {};
46 char value[MAX_VALUE_STR_LEN];
47 unsigned char i, off = 0;
48 int ret;
49
50 if (ctx->write)
51 return 0;
52
53 if (!is_tcp_mem(ctx))
54 return 0;
55
56 ret = bpf_sysctl_get_current_value(ctx, value, MAX_VALUE_STR_LEN);
57 if (ret < 0 || ret >= MAX_VALUE_STR_LEN)
58 return 0;
59
60#pragma clang loop unroll(disable)
61 for (i = 0; i < ARRAY_SIZE(tcp_mem); ++i) {
62 ret = bpf_strtoul(value + off, MAX_ULONG_STR_LEN, 0,
63 tcp_mem + i);
64 if (ret <= 0 || ret > MAX_ULONG_STR_LEN)
65 return 0;
66 off += ret & MAX_ULONG_STR_LEN;
67 }
68
69 return tcp_mem[0] < tcp_mem[1] && tcp_mem[1] < tcp_mem[2];
70}
71
72char _license[] SEC("license") = "GPL";