[PATCH openEuler-22.09 195/379] selftests/bpf: Stop using static variables for passing data to/from user-space

From: Andrii Nakryiko andrii@kernel.org

mainline inclusion from mainline-5.14-rc1 commit 256eab48e70c0eaf5b1b9af83c0588491986c7de category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I5EUVD CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...

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In preparation of skipping emitting static variables in BPF skeletons, switch all current selftests uses of static variables to pass data between BPF and user-space to use global variables.

All non-read-only `static volatile` variables become just plain global variables by dropping `static volatile` part.

Read-only `static volatile const` variables, though, still require `volatile` modifier, otherwise compiler will ignore whatever values are set from user-space.

Few static linker tests are using name-conflicting static variables to validate that static linker still properly handles static variables and doesn't trip up on name conflicts.

Signed-off-by: Andrii Nakryiko andrii@kernel.org Signed-off-by: Alexei Starovoitov ast@kernel.org Link: https://lore.kernel.org/bpf/20210507054119.270888-4-andrii@kernel.org (cherry picked from commit 256eab48e70c0eaf5b1b9af83c0588491986c7de) Signed-off-by: Wang Yufen wangyufen@huawei.com

Conflicts: tools/testing/selftests/bpf/progs/test_check_mtu.c tools/testing/selftests/bpf/progs/test_snprintf_single.c tools/testing/selftests/bpf/progs/test_sockmap_listen.c

Signed-off-by: Wang Yufen wangyufen@huawei.com --- tools/testing/selftests/bpf/prog_tests/send_signal.c | 2 +- tools/testing/selftests/bpf/prog_tests/skeleton.c | 6 ++---- tools/testing/selftests/bpf/prog_tests/static_linked.c | 5 ----- tools/testing/selftests/bpf/progs/bpf_iter_test_kern4.c | 4 ++-- tools/testing/selftests/bpf/progs/kfree_skb.c | 4 ++-- tools/testing/selftests/bpf/progs/tailcall3.c | 2 +- tools/testing/selftests/bpf/progs/tailcall4.c | 2 +- tools/testing/selftests/bpf/progs/tailcall5.c | 2 +- tools/testing/selftests/bpf/progs/tailcall_bpf2bpf2.c | 2 +- tools/testing/selftests/bpf/progs/tailcall_bpf2bpf4.c | 2 +- tools/testing/selftests/bpf/progs/test_cls_redirect.c | 4 ++-- tools/testing/selftests/bpf/progs/test_global_func_args.c | 2 +- tools/testing/selftests/bpf/progs/test_rdonly_maps.c | 6 +++--- tools/testing/selftests/bpf/progs/test_skeleton.c | 4 ++-- tools/testing/selftests/bpf/progs/test_sockmap_listen.c | 2 +- tools/testing/selftests/bpf/progs/test_static_linked1.c | 8 ++++---- tools/testing/selftests/bpf/progs/test_static_linked2.c | 8 ++++---- 17 files changed, 29 insertions(+), 36 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/send_signal.c b/tools/testing/selftests/bpf/prog_tests/send_signal.c index 75b72c751772..1931de5275e5 100644 --- a/tools/testing/selftests/bpf/prog_tests/send_signal.c +++ b/tools/testing/selftests/bpf/prog_tests/send_signal.c @@ -4,7 +4,7 @@ #include <sys/resource.h> #include "test_send_signal_kern.skel.h"

-static volatile int sigusr1_received = 0; +int sigusr1_received = 0;

static void sigusr1_handler(int signum) { diff --git a/tools/testing/selftests/bpf/prog_tests/skeleton.c b/tools/testing/selftests/bpf/prog_tests/skeleton.c index fe87b77af459..f6f130c99b8c 100644 --- a/tools/testing/selftests/bpf/prog_tests/skeleton.c +++ b/tools/testing/selftests/bpf/prog_tests/skeleton.c @@ -82,10 +82,8 @@ void test_skeleton(void) CHECK(data->out2 != 2, "res2", "got %lld != exp %d\n", data->out2, 2); CHECK(bss->out3 != 3, "res3", "got %d != exp %d\n", (int)bss->out3, 3); CHECK(bss->out4 != 4, "res4", "got %lld != exp %d\n", bss->out4, 4); - CHECK(bss->handler_out5.a != 5, "res5", "got %d != exp %d\n", - bss->handler_out5.a, 5); - CHECK(bss->handler_out5.b != 6, "res6", "got %lld != exp %d\n", - bss->handler_out5.b, 6); + CHECK(bss->out5.a != 5, "res5", "got %d != exp %d\n", bss->out5.a, 5); + CHECK(bss->out5.b != 6, "res6", "got %lld != exp %d\n", bss->out5.b, 6); CHECK(bss->out6 != 14, "res7", "got %d != exp %d\n", bss->out6, 14);

CHECK(bss->bpf_syscall != kcfg->CONFIG_BPF_SYSCALL, "ext1", diff --git a/tools/testing/selftests/bpf/prog_tests/static_linked.c b/tools/testing/selftests/bpf/prog_tests/static_linked.c index 46556976dccc..ab6acbaf9d8c 100644 --- a/tools/testing/selftests/bpf/prog_tests/static_linked.c +++ b/tools/testing/selftests/bpf/prog_tests/static_linked.c @@ -14,12 +14,7 @@ void test_static_linked(void) return;

skel->rodata->rovar1 = 1; - skel->bss->static_var1 = 2; - skel->bss->static_var11 = 3; - skel->rodata->rovar2 = 4; - skel->bss->static_var2 = 5; - skel->bss->static_var22 = 6;

err = test_static_linked__load(skel); if (!ASSERT_OK(err, "skel_load")) diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_test_kern4.c b/tools/testing/selftests/bpf/progs/bpf_iter_test_kern4.c index ee49493dc125..400fdf8d6233 100644 --- a/tools/testing/selftests/bpf/progs/bpf_iter_test_kern4.c +++ b/tools/testing/selftests/bpf/progs/bpf_iter_test_kern4.c @@ -9,8 +9,8 @@ __u32 map1_id = 0, map2_id = 0; __u32 map1_accessed = 0, map2_accessed = 0; __u64 map1_seqnum = 0, map2_seqnum1 = 0, map2_seqnum2 = 0;

-static volatile const __u32 print_len; -static volatile const __u32 ret1; +volatile const __u32 print_len; +volatile const __u32 ret1;

SEC("iter/bpf_map") int dump_bpf_map(struct bpf_iter__bpf_map *ctx) diff --git a/tools/testing/selftests/bpf/progs/kfree_skb.c b/tools/testing/selftests/bpf/progs/kfree_skb.c index a46a264ce24e..55e283050cab 100644 --- a/tools/testing/selftests/bpf/progs/kfree_skb.c +++ b/tools/testing/selftests/bpf/progs/kfree_skb.c @@ -109,10 +109,10 @@ int BPF_PROG(trace_kfree_skb, struct sk_buff *skb, void *location) return 0; }

-static volatile struct { +struct { bool fentry_test_ok; bool fexit_test_ok; -} result; +} result = {};

SEC("fentry/eth_type_trans") int BPF_PROG(fentry_eth_type_trans, struct sk_buff *skb, struct net_device *dev, diff --git a/tools/testing/selftests/bpf/progs/tailcall3.c b/tools/testing/selftests/bpf/progs/tailcall3.c index 739dc2a51e74..910858fe078a 100644 --- a/tools/testing/selftests/bpf/progs/tailcall3.c +++ b/tools/testing/selftests/bpf/progs/tailcall3.c @@ -10,7 +10,7 @@ struct { __uint(value_size, sizeof(__u32)); } jmp_table SEC(".maps");

-static volatile int count; +int count = 0;

SEC("classifier/0") int bpf_func_0(struct __sk_buff *skb) diff --git a/tools/testing/selftests/bpf/progs/tailcall4.c b/tools/testing/selftests/bpf/progs/tailcall4.c index f82075b47d7d..bd4be135c39d 100644 --- a/tools/testing/selftests/bpf/progs/tailcall4.c +++ b/tools/testing/selftests/bpf/progs/tailcall4.c @@ -10,7 +10,7 @@ struct { __uint(value_size, sizeof(__u32)); } jmp_table SEC(".maps");

-static volatile int selector; +int selector = 0;

#define TAIL_FUNC(x) \ SEC("classifier/" #x) \ diff --git a/tools/testing/selftests/bpf/progs/tailcall5.c b/tools/testing/selftests/bpf/progs/tailcall5.c index ce5450744fd4..adf30a33064e 100644 --- a/tools/testing/selftests/bpf/progs/tailcall5.c +++ b/tools/testing/selftests/bpf/progs/tailcall5.c @@ -10,7 +10,7 @@ struct { __uint(value_size, sizeof(__u32)); } jmp_table SEC(".maps");

-static volatile int selector; +int selector = 0;

#define TAIL_FUNC(x) \ SEC("classifier/" #x) \ diff --git a/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf2.c b/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf2.c index 7b1c04183824..3cc4c12817b5 100644 --- a/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf2.c +++ b/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf2.c @@ -20,7 +20,7 @@ int subprog_tail(struct __sk_buff *skb) return 1; }

-static volatile int count; +int count = 0;

SEC("classifier/0") int bpf_func_0(struct __sk_buff *skb) diff --git a/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf4.c b/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf4.c index 9a1b166b7fbe..77df6d4db895 100644 --- a/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf4.c +++ b/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf4.c @@ -9,7 +9,7 @@ struct { __uint(value_size, sizeof(__u32)); } jmp_table SEC(".maps");

-static volatile int count; +int count = 0;

__noinline int subprog_tail_2(struct __sk_buff *skb) diff --git a/tools/testing/selftests/bpf/progs/test_cls_redirect.c b/tools/testing/selftests/bpf/progs/test_cls_redirect.c index c9f8464996ea..8eaeef01a925 100644 --- a/tools/testing/selftests/bpf/progs/test_cls_redirect.c +++ b/tools/testing/selftests/bpf/progs/test_cls_redirect.c @@ -39,8 +39,8 @@ char _license[] SEC("license") = "Dual BSD/GPL"; /** * Destination port and IP used for UDP encapsulation. */ -static volatile const __be16 ENCAPSULATION_PORT; -static volatile const __be32 ENCAPSULATION_IP; +volatile const __be16 ENCAPSULATION_PORT; +volatile const __be32 ENCAPSULATION_IP;

typedef struct { uint64_t processed_packets_total; diff --git a/tools/testing/selftests/bpf/progs/test_global_func_args.c b/tools/testing/selftests/bpf/progs/test_global_func_args.c index cae309538a9e..e712bf77daae 100644 --- a/tools/testing/selftests/bpf/progs/test_global_func_args.c +++ b/tools/testing/selftests/bpf/progs/test_global_func_args.c @@ -8,7 +8,7 @@ struct S { int v; };

-static volatile struct S global_variable; +struct S global_variable = {};

struct { __uint(type, BPF_MAP_TYPE_ARRAY); diff --git a/tools/testing/selftests/bpf/progs/test_rdonly_maps.c b/tools/testing/selftests/bpf/progs/test_rdonly_maps.c index ecbeea2df259..fc8e8a34a3db 100644 --- a/tools/testing/selftests/bpf/progs/test_rdonly_maps.c +++ b/tools/testing/selftests/bpf/progs/test_rdonly_maps.c @@ -5,7 +5,7 @@ #include <linux/bpf.h> #include <bpf/bpf_helpers.h>

-static volatile const struct { +const struct { unsigned a[4]; /* * if the struct's size is multiple of 16, compiler will put it into @@ -15,11 +15,11 @@ static volatile const struct { char _y; } rdonly_values = { .a = {2, 3, 4, 5} };

-static volatile struct { +struct { unsigned did_run; unsigned iters; unsigned sum; -} res; +} res = {};

SEC("raw_tracepoint/sys_enter:skip_loop") int skip_loop(struct pt_regs *ctx) diff --git a/tools/testing/selftests/bpf/progs/test_skeleton.c b/tools/testing/selftests/bpf/progs/test_skeleton.c index 374ccef704e1..441fa1c552c8 100644 --- a/tools/testing/selftests/bpf/progs/test_skeleton.c +++ b/tools/testing/selftests/bpf/progs/test_skeleton.c @@ -38,11 +38,11 @@ extern int LINUX_KERNEL_VERSION __kconfig; bool bpf_syscall = 0; int kern_ver = 0;

+struct s out5 = {}; + SEC("raw_tp/sys_enter") int handler(const void *ctx) { - static volatile struct s out5; - out1 = in1; out2 = in2; out3 = in3; diff --git a/tools/testing/selftests/bpf/progs/test_sockmap_listen.c b/tools/testing/selftests/bpf/progs/test_sockmap_listen.c index a3a366c57ce1..b8539b4d29ac 100644 --- a/tools/testing/selftests/bpf/progs/test_sockmap_listen.c +++ b/tools/testing/selftests/bpf/progs/test_sockmap_listen.c @@ -28,7 +28,7 @@ struct { __type(value, unsigned int); } verdict_map SEC(".maps");

-static volatile bool test_sockmap; /* toggled by user-space */ +bool test_sockmap; /* toggled by user-space */

SEC("sk_skb/stream_parser") int prog_skb_parser(struct __sk_buff *skb) diff --git a/tools/testing/selftests/bpf/progs/test_static_linked1.c b/tools/testing/selftests/bpf/progs/test_static_linked1.c index ea1a6c4c7172..cae304045d9c 100644 --- a/tools/testing/selftests/bpf/progs/test_static_linked1.c +++ b/tools/testing/selftests/bpf/progs/test_static_linked1.c @@ -4,9 +4,9 @@ #include <linux/bpf.h> #include <bpf/bpf_helpers.h>

-/* 8-byte aligned .bss */ -static volatile long static_var1; -static volatile int static_var11; +/* 8-byte aligned .data */ +static volatile long static_var1 = 2; +static volatile int static_var2 = 3; int var1 = 0; /* 4-byte aligned .rodata */ const volatile int rovar1; @@ -21,7 +21,7 @@ static __noinline int subprog(int x) SEC("raw_tp/sys_enter") int handler1(const void *ctx) { - var1 = subprog(rovar1) + static_var1 + static_var11; + var1 = subprog(rovar1) + static_var1 + static_var2;

return 0; } diff --git a/tools/testing/selftests/bpf/progs/test_static_linked2.c b/tools/testing/selftests/bpf/progs/test_static_linked2.c index 54d8d1ab577c..c54c4e865ed8 100644 --- a/tools/testing/selftests/bpf/progs/test_static_linked2.c +++ b/tools/testing/selftests/bpf/progs/test_static_linked2.c @@ -4,9 +4,9 @@ #include <linux/bpf.h> #include <bpf/bpf_helpers.h>

-/* 4-byte aligned .bss */ -static volatile int static_var2; -static volatile int static_var22; +/* 4-byte aligned .data */ +static volatile int static_var1 = 5; +static volatile int static_var2 = 6; int var2 = 0; /* 8-byte aligned .rodata */ const volatile long rovar2; @@ -21,7 +21,7 @@ static __noinline int subprog(int x) SEC("raw_tp/sys_enter") int handler2(const void *ctx) { - var2 = subprog(rovar2) + static_var2 + static_var22; + var2 = subprog(rovar2) + static_var1 + static_var2;

return 0; }