[PATCH AUTOSEL 5.10 08/18] selftests/bpf: Add verifier test for release_reference()

[PATCH AUTOSEL 5.10 08/18] selftests/bpf: Add verifier test for release_reference()

[Sasha Levin]

From: Youlin Li <liulin063@gmail.com>

[ Upstream commit 475244f5e06beeda7b557d9dde46a5f439bf3379 ]

Add a test case to ensure that released pointer registers will not be
leaked into the map.

Before fix:

  ./test_verifier 984
    984/u reference tracking: try to leak released ptr reg FAIL
    Unexpected success to load!
    verification time 67 usec
    stack depth 4
    processed 23 insns (limit 1000000) max_states_per_insn 0 total_states 2
    peak_states 2 mark_read 1
    984/p reference tracking: try to leak released ptr reg OK
    Summary: 1 PASSED, 0 SKIPPED, 1 FAILED

After fix:

  ./test_verifier 984
    984/u reference tracking: try to leak released ptr reg OK
    984/p reference tracking: try to leak released ptr reg OK
    Summary: 2 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Youlin Li <liulin063@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221103093440.3161-2-liulin063@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 .../selftests/bpf/verifier/ref_tracking.c     | 36 +++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/tools/testing/selftests/bpf/verifier/ref_tracking.c b/tools/testing/selftests/bpf/verifier/ref_tracking.c
index 006b5bd99c08..525d810b10b8 100644
--- a/tools/testing/selftests/bpf/verifier/ref_tracking.c
+++ b/tools/testing/selftests/bpf/verifier/ref_tracking.c
@@ -901,3 +901,39 @@
 	.result_unpriv = REJECT,
 	.errstr_unpriv = "unknown func",
 },
+{
+	"reference tracking: try to leak released ptr reg",
+	.insns = {
+		BPF_MOV64_IMM(BPF_REG_0, 0),
+		BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_0, -4),
+		BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+		BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -4),
+		BPF_LD_MAP_FD(BPF_REG_1, 0),
+		BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+		BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
+		BPF_EXIT_INSN(),
+		BPF_MOV64_REG(BPF_REG_9, BPF_REG_0),
+
+		BPF_MOV64_IMM(BPF_REG_0, 0),
+		BPF_LD_MAP_FD(BPF_REG_1, 0),
+		BPF_MOV64_IMM(BPF_REG_2, 8),
+		BPF_MOV64_IMM(BPF_REG_3, 0),
+		BPF_EMIT_CALL(BPF_FUNC_ringbuf_reserve),
+		BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
+		BPF_EXIT_INSN(),
+		BPF_MOV64_REG(BPF_REG_8, BPF_REG_0),
+
+		BPF_MOV64_REG(BPF_REG_1, BPF_REG_8),
+		BPF_MOV64_IMM(BPF_REG_2, 0),
+		BPF_EMIT_CALL(BPF_FUNC_ringbuf_discard),
+		BPF_MOV64_IMM(BPF_REG_0, 0),
+
+		BPF_STX_MEM(BPF_DW, BPF_REG_9, BPF_REG_8, 0),
+		BPF_EXIT_INSN()
+	},
+	.fixup_map_array_48b = { 4 },
+	.fixup_map_ringbuf = { 11 },
+	.result = ACCEPT,
+	.result_unpriv = REJECT,
+	.errstr_unpriv = "R8 !read_ok"
+},
-- 
2.35.1

[PATCH AUTOSEL 5.10 16/18] arm64/syscall: Include asm/ptrace.h in syscall_wrapper header.

[Sasha Levin]

From: Kuniyuki Iwashima <kuniyu@amazon.com>

[ Upstream commit acfc35cfcee5df419391671ef1a631f43feee4e3 ]

Add the same change for ARM64 as done in the commit 9440c4294160
("x86/syscall: Include asm/ptrace.h in syscall_wrapper header") to
make sure all syscalls see 'struct pt_regs' definition and resulted
BTF for '__arm64_sys_*(struct pt_regs *regs)' functions point to
actual struct.

Without this patch, the BPF verifier refuses to load a tracing prog
which accesses pt_regs.

  bpf(BPF_PROG_LOAD, {prog_type=0x1a, ...}, 128) = -1 EACCES

With this patch, we can see the correct error, which saves us time
in debugging the prog.

  bpf(BPF_PROG_LOAD, {prog_type=0x1a, ...}, 128) = 4
  bpf(BPF_RAW_TRACEPOINT_OPEN, {raw_tracepoint={name=NULL, prog_fd=4}}, 128) = -1 ENOTSUPP

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20221031215728.50389-1-kuniyu@amazon.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/arm64/include/asm/syscall_wrapper.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/include/asm/syscall_wrapper.h b/arch/arm64/include/asm/syscall_wrapper.h
index b383b4802a7b..d30217c21eff 100644
--- a/arch/arm64/include/asm/syscall_wrapper.h
+++ b/arch/arm64/include/asm/syscall_wrapper.h
@@ -8,7 +8,7 @@
 #ifndef __ASM_SYSCALL_WRAPPER_H
 #define __ASM_SYSCALL_WRAPPER_H
 
-struct pt_regs;
+#include <asm/ptrace.h>
 
 #define SC_ARM64_REGS_TO_ARGS(x, ...)				\
 	__MAP(x,__SC_ARGS					\
-- 
2.35.1