bpf: selftest: Add ref_tracking verifier test for bpf_skc casting
The patch tests for: 1. bpf_sk_release() can be called on a tcp_sock btf_id ptr. 2. Ensure the tcp_sock btf_id pointer cannot be used after bpf_sk_release(). Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Lorenz Bauer <lmb@cloudflare.com> Link: https://lore.kernel.org/bpf/20200925000421.3857616-1-kafai@fb.com
This commit is contained in:
committed by
Alexei Starovoitov
parent
27e5203bd9
commit
5d13746dd8
@ -854,3 +854,50 @@
|
||||
.errstr = "Unreleased reference",
|
||||
.result = REJECT,
|
||||
},
|
||||
{
|
||||
"reference tracking: bpf_sk_release(btf_tcp_sock)",
|
||||
.insns = {
|
||||
BPF_SK_LOOKUP(sk_lookup_tcp),
|
||||
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
|
||||
BPF_EXIT_INSN(),
|
||||
BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
|
||||
BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
|
||||
BPF_EMIT_CALL(BPF_FUNC_skc_to_tcp_sock),
|
||||
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 3),
|
||||
BPF_MOV64_REG(BPF_REG_1, BPF_REG_6),
|
||||
BPF_EMIT_CALL(BPF_FUNC_sk_release),
|
||||
BPF_EXIT_INSN(),
|
||||
BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
|
||||
BPF_EMIT_CALL(BPF_FUNC_sk_release),
|
||||
BPF_EXIT_INSN(),
|
||||
},
|
||||
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
|
||||
.result = ACCEPT,
|
||||
.result_unpriv = REJECT,
|
||||
.errstr_unpriv = "unknown func",
|
||||
},
|
||||
{
|
||||
"reference tracking: use ptr from bpf_skc_to_tcp_sock() after release",
|
||||
.insns = {
|
||||
BPF_SK_LOOKUP(sk_lookup_tcp),
|
||||
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
|
||||
BPF_EXIT_INSN(),
|
||||
BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
|
||||
BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
|
||||
BPF_EMIT_CALL(BPF_FUNC_skc_to_tcp_sock),
|
||||
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 3),
|
||||
BPF_MOV64_REG(BPF_REG_1, BPF_REG_6),
|
||||
BPF_EMIT_CALL(BPF_FUNC_sk_release),
|
||||
BPF_EXIT_INSN(),
|
||||
BPF_MOV64_REG(BPF_REG_7, BPF_REG_0),
|
||||
BPF_MOV64_REG(BPF_REG_1, BPF_REG_6),
|
||||
BPF_EMIT_CALL(BPF_FUNC_sk_release),
|
||||
BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_7, 0),
|
||||
BPF_EXIT_INSN(),
|
||||
},
|
||||
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
|
||||
.result = REJECT,
|
||||
.errstr = "invalid mem access",
|
||||
.result_unpriv = REJECT,
|
||||
.errstr_unpriv = "unknown func",
|
||||
},
|
||||
|
Reference in New Issue
Block a user