@@ -17,6 +17,7 @@
#include "verifier_cgroup_skb.skel.h"
#include "verifier_cgroup_storage.skel.h"
#include "verifier_const_or.skel.h"
+#include "verifier_ctx.skel.h"
#include "verifier_ctx_sk_msg.skel.h"
#include "verifier_direct_stack_access_wraparound.skel.h"
#include "verifier_div0.skel.h"
@@ -94,6 +95,7 @@ void test_verifier_cgroup_inv_retcode(void) { RUN(verifier_cgroup_inv_retcode)
void test_verifier_cgroup_skb(void) { RUN(verifier_cgroup_skb); }
void test_verifier_cgroup_storage(void) { RUN(verifier_cgroup_storage); }
void test_verifier_const_or(void) { RUN(verifier_const_or); }
+void test_verifier_ctx(void) { RUN(verifier_ctx); }
void test_verifier_ctx_sk_msg(void) { RUN(verifier_ctx_sk_msg); }
void test_verifier_direct_stack_access_wraparound(void) { RUN(verifier_direct_stack_access_wraparound); }
void test_verifier_div0(void) { RUN(verifier_div0); }
new file mode 100644
@@ -0,0 +1,221 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Converted from tools/testing/selftests/bpf/verifier/ctx.c */
+
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+#include "bpf_misc.h"
+
+SEC("tc")
+__description("context stores via BPF_ATOMIC")
+__failure __msg("BPF_ATOMIC stores into R1 ctx is not allowed")
+__naked void context_stores_via_bpf_atomic(void)
+{
+ asm volatile (" \
+ r0 = 0; \
+ lock *(u32 *)(r1 + %[__sk_buff_mark]) += w0; \
+ exit; \
+" :
+ : __imm_const(__sk_buff_mark, offsetof(struct __sk_buff, mark))
+ : __clobber_all);
+}
+
+SEC("tc")
+__description("arithmetic ops make PTR_TO_CTX unusable")
+__failure __msg("dereference of modified ctx ptr")
+__naked void make_ptr_to_ctx_unusable(void)
+{
+ asm volatile (" \
+ r1 += %[__imm_0]; \
+ r0 = *(u32*)(r1 + %[__sk_buff_mark]); \
+ exit; \
+" :
+ : __imm_const(__imm_0,
+ offsetof(struct __sk_buff, data) - offsetof(struct __sk_buff, mark)),
+ __imm_const(__sk_buff_mark, offsetof(struct __sk_buff, mark))
+ : __clobber_all);
+}
+
+SEC("tc")
+__description("pass unmodified ctx pointer to helper")
+__success __retval(0)
+__naked void unmodified_ctx_pointer_to_helper(void)
+{
+ asm volatile (" \
+ r2 = 0; \
+ call %[bpf_csum_update]; \
+ r0 = 0; \
+ exit; \
+" :
+ : __imm(bpf_csum_update)
+ : __clobber_all);
+}
+
+SEC("tc")
+__description("pass modified ctx pointer to helper, 1")
+__failure __msg("negative offset ctx ptr R1 off=-612 disallowed")
+__naked void ctx_pointer_to_helper_1(void)
+{
+ asm volatile (" \
+ r1 += -612; \
+ r2 = 0; \
+ call %[bpf_csum_update]; \
+ r0 = 0; \
+ exit; \
+" :
+ : __imm(bpf_csum_update)
+ : __clobber_all);
+}
+
+SEC("socket")
+__description("pass modified ctx pointer to helper, 2")
+__failure __msg("negative offset ctx ptr R1 off=-612 disallowed")
+__failure_unpriv __msg_unpriv("negative offset ctx ptr R1 off=-612 disallowed")
+__naked void ctx_pointer_to_helper_2(void)
+{
+ asm volatile (" \
+ r1 += -612; \
+ call %[bpf_get_socket_cookie]; \
+ r0 = 0; \
+ exit; \
+" :
+ : __imm(bpf_get_socket_cookie)
+ : __clobber_all);
+}
+
+SEC("tc")
+__description("pass modified ctx pointer to helper, 3")
+__failure __msg("variable ctx access var_off=(0x0; 0x4)")
+__naked void ctx_pointer_to_helper_3(void)
+{
+ asm volatile (" \
+ r3 = *(u32*)(r1 + 0); \
+ r3 &= 4; \
+ r1 += r3; \
+ r2 = 0; \
+ call %[bpf_csum_update]; \
+ r0 = 0; \
+ exit; \
+" :
+ : __imm(bpf_csum_update)
+ : __clobber_all);
+}
+
+SEC("cgroup/sendmsg6")
+__description("pass ctx or null check, 1: ctx")
+__success
+__naked void or_null_check_1_ctx(void)
+{
+ asm volatile (" \
+ call %[bpf_get_netns_cookie]; \
+ r0 = 0; \
+ exit; \
+" :
+ : __imm(bpf_get_netns_cookie)
+ : __clobber_all);
+}
+
+SEC("cgroup/sendmsg6")
+__description("pass ctx or null check, 2: null")
+__success
+__naked void or_null_check_2_null(void)
+{
+ asm volatile (" \
+ r1 = 0; \
+ call %[bpf_get_netns_cookie]; \
+ r0 = 0; \
+ exit; \
+" :
+ : __imm(bpf_get_netns_cookie)
+ : __clobber_all);
+}
+
+SEC("cgroup/sendmsg6")
+__description("pass ctx or null check, 3: 1")
+__failure __msg("R1 type=scalar expected=ctx")
+__naked void or_null_check_3_1(void)
+{
+ asm volatile (" \
+ r1 = 1; \
+ call %[bpf_get_netns_cookie]; \
+ r0 = 0; \
+ exit; \
+" :
+ : __imm(bpf_get_netns_cookie)
+ : __clobber_all);
+}
+
+SEC("cgroup/sendmsg6")
+__description("pass ctx or null check, 4: ctx - const")
+__failure __msg("negative offset ctx ptr R1 off=-612 disallowed")
+__naked void null_check_4_ctx_const(void)
+{
+ asm volatile (" \
+ r1 += -612; \
+ call %[bpf_get_netns_cookie]; \
+ r0 = 0; \
+ exit; \
+" :
+ : __imm(bpf_get_netns_cookie)
+ : __clobber_all);
+}
+
+SEC("cgroup/connect4")
+__description("pass ctx or null check, 5: null (connect)")
+__success
+__naked void null_check_5_null_connect(void)
+{
+ asm volatile (" \
+ r1 = 0; \
+ call %[bpf_get_netns_cookie]; \
+ r0 = 0; \
+ exit; \
+" :
+ : __imm(bpf_get_netns_cookie)
+ : __clobber_all);
+}
+
+SEC("cgroup/post_bind4")
+__description("pass ctx or null check, 6: null (bind)")
+__success
+__naked void null_check_6_null_bind(void)
+{
+ asm volatile (" \
+ r1 = 0; \
+ call %[bpf_get_netns_cookie]; \
+ r0 = 0; \
+ exit; \
+" :
+ : __imm(bpf_get_netns_cookie)
+ : __clobber_all);
+}
+
+SEC("cgroup/post_bind4")
+__description("pass ctx or null check, 7: ctx (bind)")
+__success
+__naked void null_check_7_ctx_bind(void)
+{
+ asm volatile (" \
+ call %[bpf_get_socket_cookie]; \
+ r0 = 0; \
+ exit; \
+" :
+ : __imm(bpf_get_socket_cookie)
+ : __clobber_all);
+}
+
+SEC("cgroup/post_bind4")
+__description("pass ctx or null check, 8: null (bind)")
+__failure __msg("R1 type=scalar expected=ctx")
+__naked void null_check_8_null_bind(void)
+{
+ asm volatile (" \
+ r1 = 0; \
+ call %[bpf_get_socket_cookie]; \
+ r0 = 0; \
+ exit; \
+" :
+ : __imm(bpf_get_socket_cookie)
+ : __clobber_all);
+}
+
+char _license[] SEC("license") = "GPL";
deleted file mode 100644
@@ -1,186 +0,0 @@
-{
- "context stores via BPF_ATOMIC",
- .insns = {
- BPF_MOV64_IMM(BPF_REG_0, 0),
- BPF_ATOMIC_OP(BPF_W, BPF_ADD, BPF_REG_1, BPF_REG_0, offsetof(struct __sk_buff, mark)),
- BPF_EXIT_INSN(),
- },
- .errstr = "BPF_ATOMIC stores into R1 ctx is not allowed",
- .result = REJECT,
- .prog_type = BPF_PROG_TYPE_SCHED_CLS,
-},
-{
- "arithmetic ops make PTR_TO_CTX unusable",
- .insns = {
- BPF_ALU64_IMM(BPF_ADD, BPF_REG_1,
- offsetof(struct __sk_buff, data) -
- offsetof(struct __sk_buff, mark)),
- BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
- offsetof(struct __sk_buff, mark)),
- BPF_EXIT_INSN(),
- },
- .errstr = "dereference of modified ctx ptr",
- .result = REJECT,
- .prog_type = BPF_PROG_TYPE_SCHED_CLS,
-},
-{
- "pass unmodified ctx pointer to helper",
- .insns = {
- BPF_MOV64_IMM(BPF_REG_2, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
- BPF_FUNC_csum_update),
- BPF_MOV64_IMM(BPF_REG_0, 0),
- BPF_EXIT_INSN(),
- },
- .prog_type = BPF_PROG_TYPE_SCHED_CLS,
- .result = ACCEPT,
-},
-{
- "pass modified ctx pointer to helper, 1",
- .insns = {
- BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -612),
- BPF_MOV64_IMM(BPF_REG_2, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
- BPF_FUNC_csum_update),
- BPF_MOV64_IMM(BPF_REG_0, 0),
- BPF_EXIT_INSN(),
- },
- .prog_type = BPF_PROG_TYPE_SCHED_CLS,
- .result = REJECT,
- .errstr = "negative offset ctx ptr R1 off=-612 disallowed",
-},
-{
- "pass modified ctx pointer to helper, 2",
- .insns = {
- BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -612),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
- BPF_FUNC_get_socket_cookie),
- BPF_MOV64_IMM(BPF_REG_0, 0),
- BPF_EXIT_INSN(),
- },
- .result_unpriv = REJECT,
- .result = REJECT,
- .errstr_unpriv = "negative offset ctx ptr R1 off=-612 disallowed",
- .errstr = "negative offset ctx ptr R1 off=-612 disallowed",
-},
-{
- "pass modified ctx pointer to helper, 3",
- .insns = {
- BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, 0),
- BPF_ALU64_IMM(BPF_AND, BPF_REG_3, 4),
- BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_3),
- BPF_MOV64_IMM(BPF_REG_2, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
- BPF_FUNC_csum_update),
- BPF_MOV64_IMM(BPF_REG_0, 0),
- BPF_EXIT_INSN(),
- },
- .prog_type = BPF_PROG_TYPE_SCHED_CLS,
- .result = REJECT,
- .errstr = "variable ctx access var_off=(0x0; 0x4)",
-},
-{
- "pass ctx or null check, 1: ctx",
- .insns = {
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
- BPF_FUNC_get_netns_cookie),
- BPF_MOV64_IMM(BPF_REG_0, 0),
- BPF_EXIT_INSN(),
- },
- .prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
- .expected_attach_type = BPF_CGROUP_UDP6_SENDMSG,
- .result = ACCEPT,
-},
-{
- "pass ctx or null check, 2: null",
- .insns = {
- BPF_MOV64_IMM(BPF_REG_1, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
- BPF_FUNC_get_netns_cookie),
- BPF_MOV64_IMM(BPF_REG_0, 0),
- BPF_EXIT_INSN(),
- },
- .prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
- .expected_attach_type = BPF_CGROUP_UDP6_SENDMSG,
- .result = ACCEPT,
-},
-{
- "pass ctx or null check, 3: 1",
- .insns = {
- BPF_MOV64_IMM(BPF_REG_1, 1),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
- BPF_FUNC_get_netns_cookie),
- BPF_MOV64_IMM(BPF_REG_0, 0),
- BPF_EXIT_INSN(),
- },
- .prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
- .expected_attach_type = BPF_CGROUP_UDP6_SENDMSG,
- .result = REJECT,
- .errstr = "R1 type=scalar expected=ctx",
-},
-{
- "pass ctx or null check, 4: ctx - const",
- .insns = {
- BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -612),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
- BPF_FUNC_get_netns_cookie),
- BPF_MOV64_IMM(BPF_REG_0, 0),
- BPF_EXIT_INSN(),
- },
- .prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
- .expected_attach_type = BPF_CGROUP_UDP6_SENDMSG,
- .result = REJECT,
- .errstr = "negative offset ctx ptr R1 off=-612 disallowed",
-},
-{
- "pass ctx or null check, 5: null (connect)",
- .insns = {
- BPF_MOV64_IMM(BPF_REG_1, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
- BPF_FUNC_get_netns_cookie),
- BPF_MOV64_IMM(BPF_REG_0, 0),
- BPF_EXIT_INSN(),
- },
- .prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
- .expected_attach_type = BPF_CGROUP_INET4_CONNECT,
- .result = ACCEPT,
-},
-{
- "pass ctx or null check, 6: null (bind)",
- .insns = {
- BPF_MOV64_IMM(BPF_REG_1, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
- BPF_FUNC_get_netns_cookie),
- BPF_MOV64_IMM(BPF_REG_0, 0),
- BPF_EXIT_INSN(),
- },
- .prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
- .expected_attach_type = BPF_CGROUP_INET4_POST_BIND,
- .result = ACCEPT,
-},
-{
- "pass ctx or null check, 7: ctx (bind)",
- .insns = {
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
- BPF_FUNC_get_socket_cookie),
- BPF_MOV64_IMM(BPF_REG_0, 0),
- BPF_EXIT_INSN(),
- },
- .prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
- .expected_attach_type = BPF_CGROUP_INET4_POST_BIND,
- .result = ACCEPT,
-},
-{
- "pass ctx or null check, 8: null (bind)",
- .insns = {
- BPF_MOV64_IMM(BPF_REG_1, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
- BPF_FUNC_get_socket_cookie),
- BPF_MOV64_IMM(BPF_REG_0, 0),
- BPF_EXIT_INSN(),
- },
- .prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
- .expected_attach_type = BPF_CGROUP_INET4_POST_BIND,
- .result = REJECT,
- .errstr = "R1 type=scalar expected=ctx",
-},
Test verifier/ctx automatically converted to use inline assembly. Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> --- .../selftests/bpf/prog_tests/verifier.c | 2 + .../selftests/bpf/progs/verifier_ctx.c | 221 ++++++++++++++++++ tools/testing/selftests/bpf/verifier/ctx.c | 186 --------------- 3 files changed, 223 insertions(+), 186 deletions(-) create mode 100644 tools/testing/selftests/bpf/progs/verifier_ctx.c delete mode 100644 tools/testing/selftests/bpf/verifier/ctx.c