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-rw-r--r--include/linux/bpf.h4
-rw-r--r--kernel/bpf/bpf_struct_ops.c141
-rw-r--r--net/bpf/bpf_dummy_struct_ops.c12
-rw-r--r--net/ipv4/tcp_cong.c6
-rw-r--r--tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h44
-rw-r--r--tools/testing/selftests/bpf/prog_tests/test_struct_ops_multi_pages.c30
-rw-r--r--tools/testing/selftests/bpf/progs/struct_ops_multi_pages.c102
7 files changed, 279 insertions, 60 deletions
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 814dc913a968..785660810e6a 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1763,7 +1763,9 @@ int bpf_struct_ops_prepare_trampoline(struct bpf_tramp_links *tlinks,
struct bpf_tramp_link *link,
const struct btf_func_model *model,
void *stub_func,
- void *image, void *image_end);
+ void **image, u32 *image_off,
+ bool allow_alloc);
+void bpf_struct_ops_image_free(void *image);
static inline bool bpf_try_module_get(const void *data, struct module *owner)
{
if (owner == BPF_MODULE_OWNER)
diff --git a/kernel/bpf/bpf_struct_ops.c b/kernel/bpf/bpf_struct_ops.c
index a6019087b467..43356faaa057 100644
--- a/kernel/bpf/bpf_struct_ops.c
+++ b/kernel/bpf/bpf_struct_ops.c
@@ -18,6 +18,8 @@ struct bpf_struct_ops_value {
char data[] ____cacheline_aligned_in_smp;
};
+#define MAX_TRAMP_IMAGE_PAGES 8
+
struct bpf_struct_ops_map {
struct bpf_map map;
struct rcu_head rcu;
@@ -30,12 +32,11 @@ struct bpf_struct_ops_map {
*/
struct bpf_link **links;
u32 links_cnt;
- /* image is a page that has all the trampolines
+ u32 image_pages_cnt;
+ /* image_pages is an array of pages that has all the trampolines
* that stores the func args before calling the bpf_prog.
- * A PAGE_SIZE "image" is enough to store all trampoline for
- * "links[]".
*/
- void *image;
+ void *image_pages[MAX_TRAMP_IMAGE_PAGES];
/* The owner moduler's btf. */
struct btf *btf;
/* uvalue->data stores the kernel struct
@@ -116,6 +117,31 @@ static bool is_valid_value_type(struct btf *btf, s32 value_id,
return true;
}
+static void *bpf_struct_ops_image_alloc(void)
+{
+ void *image;
+ int err;
+
+ err = bpf_jit_charge_modmem(PAGE_SIZE);
+ if (err)
+ return ERR_PTR(err);
+ image = arch_alloc_bpf_trampoline(PAGE_SIZE);
+ if (!image) {
+ bpf_jit_uncharge_modmem(PAGE_SIZE);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ return image;
+}
+
+void bpf_struct_ops_image_free(void *image)
+{
+ if (image) {
+ arch_free_bpf_trampoline(image, PAGE_SIZE);
+ bpf_jit_uncharge_modmem(PAGE_SIZE);
+ }
+}
+
#define MAYBE_NULL_SUFFIX "__nullable"
#define MAX_STUB_NAME 128
@@ -461,6 +487,15 @@ static void bpf_struct_ops_map_put_progs(struct bpf_struct_ops_map *st_map)
}
}
+static void bpf_struct_ops_map_free_image(struct bpf_struct_ops_map *st_map)
+{
+ int i;
+
+ for (i = 0; i < st_map->image_pages_cnt; i++)
+ bpf_struct_ops_image_free(st_map->image_pages[i]);
+ st_map->image_pages_cnt = 0;
+}
+
static int check_zero_holes(const struct btf *btf, const struct btf_type *t, void *data)
{
const struct btf_member *member;
@@ -506,9 +541,12 @@ const struct bpf_link_ops bpf_struct_ops_link_lops = {
int bpf_struct_ops_prepare_trampoline(struct bpf_tramp_links *tlinks,
struct bpf_tramp_link *link,
const struct btf_func_model *model,
- void *stub_func, void *image, void *image_end)
+ void *stub_func,
+ void **_image, u32 *_image_off,
+ bool allow_alloc)
{
- u32 flags = BPF_TRAMP_F_INDIRECT;
+ u32 image_off = *_image_off, flags = BPF_TRAMP_F_INDIRECT;
+ void *image = *_image;
int size;
tlinks[BPF_TRAMP_FENTRY].links[0] = link;
@@ -518,12 +556,32 @@ int bpf_struct_ops_prepare_trampoline(struct bpf_tramp_links *tlinks,
flags |= BPF_TRAMP_F_RET_FENTRY_RET;
size = arch_bpf_trampoline_size(model, flags, tlinks, NULL);
- if (size < 0)
- return size;
- if (size > (unsigned long)image_end - (unsigned long)image)
- return -E2BIG;
- return arch_prepare_bpf_trampoline(NULL, image, image_end,
+ if (size <= 0)
+ return size ? : -EFAULT;
+
+ /* Allocate image buffer if necessary */
+ if (!image || size > PAGE_SIZE - image_off) {
+ if (!allow_alloc)
+ return -E2BIG;
+
+ image = bpf_struct_ops_image_alloc();
+ if (IS_ERR(image))
+ return PTR_ERR(image);
+ image_off = 0;
+ }
+
+ size = arch_prepare_bpf_trampoline(NULL, image + image_off,
+ image + PAGE_SIZE,
model, flags, tlinks, stub_func);
+ if (size <= 0) {
+ if (image != *_image)
+ bpf_struct_ops_image_free(image);
+ return size ? : -EFAULT;
+ }
+
+ *_image = image;
+ *_image_off = image_off + size;
+ return 0;
}
static long bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key,
@@ -539,8 +597,8 @@ static long bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key,
struct bpf_tramp_links *tlinks;
void *udata, *kdata;
int prog_fd, err;
- void *image, *image_end;
- u32 i;
+ u32 i, trampoline_start, image_off = 0;
+ void *cur_image = NULL, *image = NULL;
if (flags)
return -EINVAL;
@@ -578,8 +636,6 @@ static long bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key,
udata = &uvalue->data;
kdata = &kvalue->data;
- image = st_map->image;
- image_end = st_map->image + PAGE_SIZE;
module_type = btf_type_by_id(btf_vmlinux, st_ops_ids[IDX_MODULE_ID]);
for_each_member(i, t, member) {
@@ -658,28 +714,39 @@ static long bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key,
&bpf_struct_ops_link_lops, prog);
st_map->links[i] = &link->link;
+ trampoline_start = image_off;
err = bpf_struct_ops_prepare_trampoline(tlinks, link,
- &st_ops->func_models[i],
- *(void **)(st_ops->cfi_stubs + moff),
- image, image_end);
+ &st_ops->func_models[i],
+ *(void **)(st_ops->cfi_stubs + moff),
+ &image, &image_off,
+ st_map->image_pages_cnt < MAX_TRAMP_IMAGE_PAGES);
+ if (err)
+ goto reset_unlock;
+
+ if (cur_image != image) {
+ st_map->image_pages[st_map->image_pages_cnt++] = image;
+ cur_image = image;
+ trampoline_start = 0;
+ }
if (err < 0)
goto reset_unlock;
- *(void **)(kdata + moff) = image + cfi_get_offset();
- image += err;
+ *(void **)(kdata + moff) = image + trampoline_start + cfi_get_offset();
/* put prog_id to udata */
*(unsigned long *)(udata + moff) = prog->aux->id;
}
+ if (st_ops->validate) {
+ err = st_ops->validate(kdata);
+ if (err)
+ goto reset_unlock;
+ }
+ for (i = 0; i < st_map->image_pages_cnt; i++)
+ arch_protect_bpf_trampoline(st_map->image_pages[i], PAGE_SIZE);
+
if (st_map->map.map_flags & BPF_F_LINK) {
err = 0;
- if (st_ops->validate) {
- err = st_ops->validate(kdata);
- if (err)
- goto reset_unlock;
- }
- arch_protect_bpf_trampoline(st_map->image, PAGE_SIZE);
/* Let bpf_link handle registration & unregistration.
*
* Pair with smp_load_acquire() during lookup_elem().
@@ -688,7 +755,6 @@ static long bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key,
goto unlock;
}
- arch_protect_bpf_trampoline(st_map->image, PAGE_SIZE);
err = st_ops->reg(kdata);
if (likely(!err)) {
/* This refcnt increment on the map here after
@@ -711,9 +777,9 @@ static long bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key,
* there was a race in registering the struct_ops (under the same name) to
* a sub-system through different struct_ops's maps.
*/
- arch_unprotect_bpf_trampoline(st_map->image, PAGE_SIZE);
reset_unlock:
+ bpf_struct_ops_map_free_image(st_map);
bpf_struct_ops_map_put_progs(st_map);
memset(uvalue, 0, map->value_size);
memset(kvalue, 0, map->value_size);
@@ -780,10 +846,7 @@ static void __bpf_struct_ops_map_free(struct bpf_map *map)
if (st_map->links)
bpf_struct_ops_map_put_progs(st_map);
bpf_map_area_free(st_map->links);
- if (st_map->image) {
- arch_free_bpf_trampoline(st_map->image, PAGE_SIZE);
- bpf_jit_uncharge_modmem(PAGE_SIZE);
- }
+ bpf_struct_ops_map_free_image(st_map);
bpf_map_area_free(st_map->uvalue);
bpf_map_area_free(st_map);
}
@@ -893,20 +956,6 @@ static struct bpf_map *bpf_struct_ops_map_alloc(union bpf_attr *attr)
st_map->st_ops_desc = st_ops_desc;
map = &st_map->map;
- ret = bpf_jit_charge_modmem(PAGE_SIZE);
- if (ret)
- goto errout_free;
-
- st_map->image = arch_alloc_bpf_trampoline(PAGE_SIZE);
- if (!st_map->image) {
- /* __bpf_struct_ops_map_free() uses st_map->image as flag
- * for "charged or not". In this case, we need to unchange
- * here.
- */
- bpf_jit_uncharge_modmem(PAGE_SIZE);
- ret = -ENOMEM;
- goto errout_free;
- }
st_map->uvalue = bpf_map_area_alloc(vt->size, NUMA_NO_NODE);
st_map->links_cnt = btf_type_vlen(t);
st_map->links =
diff --git a/net/bpf/bpf_dummy_struct_ops.c b/net/bpf/bpf_dummy_struct_ops.c
index 02de71719aed..1b5f812e6972 100644
--- a/net/bpf/bpf_dummy_struct_ops.c
+++ b/net/bpf/bpf_dummy_struct_ops.c
@@ -91,6 +91,7 @@ int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr,
struct bpf_tramp_link *link = NULL;
void *image = NULL;
unsigned int op_idx;
+ u32 image_off = 0;
int prog_ret;
s32 type_id;
int err;
@@ -114,12 +115,6 @@ int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr,
goto out;
}
- image = arch_alloc_bpf_trampoline(PAGE_SIZE);
- if (!image) {
- err = -ENOMEM;
- goto out;
- }
-
link = kzalloc(sizeof(*link), GFP_USER);
if (!link) {
err = -ENOMEM;
@@ -133,7 +128,8 @@ int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr,
err = bpf_struct_ops_prepare_trampoline(tlinks, link,
&st_ops->func_models[op_idx],
&dummy_ops_test_ret_function,
- image, image + PAGE_SIZE);
+ &image, &image_off,
+ true);
if (err < 0)
goto out;
@@ -147,7 +143,7 @@ int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr,
err = -EFAULT;
out:
kfree(args);
- arch_free_bpf_trampoline(image, PAGE_SIZE);
+ bpf_struct_ops_image_free(image);
if (link)
bpf_link_put(&link->link);
kfree(tlinks);
diff --git a/net/ipv4/tcp_cong.c b/net/ipv4/tcp_cong.c
index 1b34050a7538..28ffcfbeef14 100644
--- a/net/ipv4/tcp_cong.c
+++ b/net/ipv4/tcp_cong.c
@@ -146,11 +146,7 @@ EXPORT_SYMBOL_GPL(tcp_unregister_congestion_control);
int tcp_update_congestion_control(struct tcp_congestion_ops *ca, struct tcp_congestion_ops *old_ca)
{
struct tcp_congestion_ops *existing;
- int ret;
-
- ret = tcp_validate_congestion_control(ca);
- if (ret)
- return ret;
+ int ret = 0;
ca->key = jhash(ca->name, sizeof(ca->name), strlen(ca->name));
diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h
index 971458acfac3..622d24e29d35 100644
--- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h
+++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h
@@ -43,6 +43,50 @@ struct bpf_testmod_ops {
int b;
} unsupported;
int data;
+
+ /* The following pointers are used to test the maps having multiple
+ * pages of trampolines.
+ */
+ int (*tramp_1)(int value);
+ int (*tramp_2)(int value);
+ int (*tramp_3)(int value);
+ int (*tramp_4)(int value);
+ int (*tramp_5)(int value);
+ int (*tramp_6)(int value);
+ int (*tramp_7)(int value);
+ int (*tramp_8)(int value);
+ int (*tramp_9)(int value);
+ int (*tramp_10)(int value);
+ int (*tramp_11)(int value);
+ int (*tramp_12)(int value);
+ int (*tramp_13)(int value);
+ int (*tramp_14)(int value);
+ int (*tramp_15)(int value);
+ int (*tramp_16)(int value);
+ int (*tramp_17)(int value);
+ int (*tramp_18)(int value);
+ int (*tramp_19)(int value);
+ int (*tramp_20)(int value);
+ int (*tramp_21)(int value);
+ int (*tramp_22)(int value);
+ int (*tramp_23)(int value);
+ int (*tramp_24)(int value);
+ int (*tramp_25)(int value);
+ int (*tramp_26)(int value);
+ int (*tramp_27)(int value);
+ int (*tramp_28)(int value);
+ int (*tramp_29)(int value);
+ int (*tramp_30)(int value);
+ int (*tramp_31)(int value);
+ int (*tramp_32)(int value);
+ int (*tramp_33)(int value);
+ int (*tramp_34)(int value);
+ int (*tramp_35)(int value);
+ int (*tramp_36)(int value);
+ int (*tramp_37)(int value);
+ int (*tramp_38)(int value);
+ int (*tramp_39)(int value);
+ int (*tramp_40)(int value);
};
#endif /* _BPF_TESTMOD_H */
diff --git a/tools/testing/selftests/bpf/prog_tests/test_struct_ops_multi_pages.c b/tools/testing/selftests/bpf/prog_tests/test_struct_ops_multi_pages.c
new file mode 100644
index 000000000000..645d32b5160c
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/test_struct_ops_multi_pages.c
@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2024 Meta Platforms, Inc. and affiliates. */
+#include <test_progs.h>
+
+#include "struct_ops_multi_pages.skel.h"
+
+static void do_struct_ops_multi_pages(void)
+{
+ struct struct_ops_multi_pages *skel;
+ struct bpf_link *link;
+
+ /* The size of all trampolines of skel->maps.multi_pages should be
+ * over 1 page (at least for x86).
+ */
+ skel = struct_ops_multi_pages__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "struct_ops_multi_pages_open_and_load"))
+ return;
+
+ link = bpf_map__attach_struct_ops(skel->maps.multi_pages);
+ ASSERT_OK_PTR(link, "attach_multi_pages");
+
+ bpf_link__destroy(link);
+ struct_ops_multi_pages__destroy(skel);
+}
+
+void test_struct_ops_multi_pages(void)
+{
+ if (test__start_subtest("multi_pages"))
+ do_struct_ops_multi_pages();
+}
diff --git a/tools/testing/selftests/bpf/progs/struct_ops_multi_pages.c b/tools/testing/selftests/bpf/progs/struct_ops_multi_pages.c
new file mode 100644
index 000000000000..9efcc6e4d356
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/struct_ops_multi_pages.c
@@ -0,0 +1,102 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2024 Meta Platforms, Inc. and affiliates. */
+#include <vmlinux.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+#include "../bpf_testmod/bpf_testmod.h"
+
+char _license[] SEC("license") = "GPL";
+
+#define TRAMP(x) \
+ SEC("struct_ops/tramp_" #x) \
+ int BPF_PROG(tramp_ ## x, int a) \
+ { \
+ return a; \
+ }
+
+TRAMP(1)
+TRAMP(2)
+TRAMP(3)
+TRAMP(4)
+TRAMP(5)
+TRAMP(6)
+TRAMP(7)
+TRAMP(8)
+TRAMP(9)
+TRAMP(10)
+TRAMP(11)
+TRAMP(12)
+TRAMP(13)
+TRAMP(14)
+TRAMP(15)
+TRAMP(16)
+TRAMP(17)
+TRAMP(18)
+TRAMP(19)
+TRAMP(20)
+TRAMP(21)
+TRAMP(22)
+TRAMP(23)
+TRAMP(24)
+TRAMP(25)
+TRAMP(26)
+TRAMP(27)
+TRAMP(28)
+TRAMP(29)
+TRAMP(30)
+TRAMP(31)
+TRAMP(32)
+TRAMP(33)
+TRAMP(34)
+TRAMP(35)
+TRAMP(36)
+TRAMP(37)
+TRAMP(38)
+TRAMP(39)
+TRAMP(40)
+
+#define F_TRAMP(x) .tramp_ ## x = (void *)tramp_ ## x
+
+SEC(".struct_ops.link")
+struct bpf_testmod_ops multi_pages = {
+ F_TRAMP(1),
+ F_TRAMP(2),
+ F_TRAMP(3),
+ F_TRAMP(4),
+ F_TRAMP(5),
+ F_TRAMP(6),
+ F_TRAMP(7),
+ F_TRAMP(8),
+ F_TRAMP(9),
+ F_TRAMP(10),
+ F_TRAMP(11),
+ F_TRAMP(12),
+ F_TRAMP(13),
+ F_TRAMP(14),
+ F_TRAMP(15),
+ F_TRAMP(16),
+ F_TRAMP(17),
+ F_TRAMP(18),
+ F_TRAMP(19),
+ F_TRAMP(20),
+ F_TRAMP(21),
+ F_TRAMP(22),
+ F_TRAMP(23),
+ F_TRAMP(24),
+ F_TRAMP(25),
+ F_TRAMP(26),
+ F_TRAMP(27),
+ F_TRAMP(28),
+ F_TRAMP(29),
+ F_TRAMP(30),
+ F_TRAMP(31),
+ F_TRAMP(32),
+ F_TRAMP(33),
+ F_TRAMP(34),
+ F_TRAMP(35),
+ F_TRAMP(36),
+ F_TRAMP(37),
+ F_TRAMP(38),
+ F_TRAMP(39),
+ F_TRAMP(40),
+};
generated by cgit v1.2.3-70-g09d2 (git 2.48.1) at 2025-02-16 00:00:49 +0000